Theory of Planned Behavior Analysis


Certain psychological disorders often induce irrational, maladaptive behaviors that bring about negative outcomes to the person’s health, safety, and reputation. These behaviors are commonly observed in institutionalized adults with developmental disabilities removed from society for closer monitoring and treatment by medical practitioners (Danford and Huber, 1981).

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One identified maladaptive behavior some of these individuals with developmental disabilities engage in is Pica (Albin, 1977; Kerwin & Berkowitz, 1996). This is the mouthing and ingestion of non-edible items such as paper, leaves, dirt, soil, baby powder, detergent soap, human feces, among others. Living with such behavior either as the one indulging in it or the one observing it in another person doing it can be disturbing. Aside from bringing about feelings of disgust and queasiness in others, Pica proves to endanger the person engaging in the behavior because of the risks of choking, lead poisoning, intestinal blockages, parasite development, and esophageal complications (Albin, 1977; Kuhn & Matson, 2002). Pica is not necessarily a dangerous disorder; rather it is the quality and the type of ingested substance that defines the biological risk of Pica.

For example, some children fixate on food ingredients such as raw starch and ice cubes, relatively harmlessly, while others eat things such as batteries that can cause lasting damage to the digestive tract as well as possibly fatal poisoning. In addition to the risk for lead toxicity and potential surgical requirements, Ali (2001) mentioned psychiatric difficulties and neurological complications as a result of pica behavior.

Because such behaviors pose danger, several interventions have been developed to reduce, if not extinguish pica behavior. Treatments include psychoactive drugs or electric convulsive shock (Chaturvedi, 1988; Nissen & Haggag, 1987); use of physical restraint and verbal reprimand (Bucher, Reykdal & Albin, 1976); overcorrection procedures such as thorough brushing and teeth and cleaning of mouth (Foxx & Martin, 1975); medical treatments such as the use of methylphenidate and chelation therapy (Boris et al. (1996); and employment of behavioral interventions such as response blocking and redirection (Hagopian and Adelinis, 2001).

The Theory of Planned Behavior (TPB) proposed by Icek Ajzen in 1986 claims that individuals are guided by their beliefs, namely about the outcomes of their behaviors or their behavioral beliefs; beliefs about the normative expectations of society or normative beliefs; and beliefs about factors that may facilitate or hinder the performance of their behavior or control beliefs (Ajzen, 1985). TPB was developed on the premise that behavior is determined by its intention (Rah, Hasler, Painter and Chapman-Novakofski, 2004). The intention of the behavior is formed by the person’s assessment of behavior, social contingencies related to the performance of the behavior, and the difficulty with which the behavior is performed. Armitage (2005) added that TPB is related to people’s motivation to engage in a particular behavior and that intention includes a person’s confidence in his/her ability to engage in a particular behavior.

Studies on various cases of behavior change show evidence that TPB is an effective intervention. This study will attempt to use TPB in managing an individual’s pica behavior by manipulating some variables around him or her.

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Freud’s first stage of Psychosexual development is the Oral stage. All sensations are focused on one’s mouth, as exemplified by infants and toddlers who find pleasure and satisfaction in mouthing and sucking various objects in an attempt to get acquainted with it and to be gratified by the oral sensation it brings (Freud, 1964). Such physiological pica can also be hazardous and can result in lead toxicity and parasitic infections. Ali (2001) stated that pica is considered to be a normal behavior occurrence through the age of 18 months, consistent with Freud’s Oral Stage. However, beyond this age, and with prolonged duration, pica behavior may be symptomatic of a different psychological disability or disorder. Kerwin & Berkowitz (1996) pointed out that pica behavior has been demonstrated in adults with developmental disabilities as well as young children aged three years and under and pregnant women. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) stipulates that pica behavior must follow specific criteria including “The eating of non-nutritive substance is inappropriate to the developmental level”.

This study recognizes that pica behavior can lead to serious medical complications or conditions, possibly even death. Since most individuals with developmental disabilities such as mental retardation or autism are involved, they need constant supervision so that pica behavior is prevented. An effective intervention is necessary to empower the individual engaging in pica behavior to manage the pica on his or her own.

A promising framework by which to examine Pica and the treatment to Pica that will make a distinction between normative and deviant non-nutritive eating is the use of the Theory of Planned Behavior conceptualized by Ajzen (1985). It applies the theory of reasoned action to a variety of situations and scenarios. In the theory of planned behavior, actions are tied to various attitudes, thus behavior is a construct of intent, and it can be predicted by an analysis of attitude and the surroundings of an individual. TPB means that no behavior is truly irrational, but that a person is operating under a series of beliefs that compels them to action. Applying the theory to Pica, people who eat objects that are clearly not food items are still subconsciously doing so because they believe that the behavior is necessary, or that it provides some sort of benefit. Behavioral intention is created through the development of beliefs and assumptions, and behavior comes out of that intention.

For the theory to be useful in the treatment and the diagnosis of Pica behavior, researchers must fully understand what aspects of cultural and environmental influence have a role in the encouraging and discouraging of Pica. The theoretical construct provided by TPB requires an assessment of patient attitudes and also an assumption that on some level patients are acting in what they believe to be their own best interests. Taking potentially dangerous behavior like Pica as an example, there is a foundational problem in the assumptions that an individual is operating under when they eat something that is inedible and potentially dangerous. Additionally, since Pica is often something that manifests in people with developmental disabilities, it is possible that there is an attitude change against Pica behavior that occurs in mentally healthy people but that fails to trigger in people with developmental disabilities. People with developmental retardation might also fail to understand societal norms, so they are deprived of one of the major reinforcing attitudes that would discourage deviant Pica behavior. On the other extreme, in societies where Pica is mainstream and accepted, there are no negative attitudes that are placed on the individual by either observation of norms or by a conversation with peer groups, so the behavior is never eliminated. Since babies go through some form of Pica behavior in their developmental stages, is it possible that the behavior is organic to human development and that it is only later erased due to societal externalities such as pressure from parents?

Problem Statement

Pica behavior can lead to fatal health risks. Does the availability of food influence the presentation of pica behavior? Through the use of the TPB theory, manipulation of one’s behavioral, normative and control beliefs can influence pica behavior rates. Independent variables would be the individual’s beliefs about eating real food and pica items, placement location, and access to food. The dependent variable is pica behavior.

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Research Question and Hypothesis

The main research question for this study is: “Will TPB be effective as an intervention to reduce or extinguish pica behaviors?”

Hypothesis #1: Through the use of TPB, there will be a reduction in the number of pica attempts made.

Hypothesis #2: After interventions based on TPB, positive alternative behaviors, i.e. correctly seeking food will increase and pica behavior will decrease.

Null hypothesis: After receiving interventions based on TPB, pica behavior rates will not change compared to previous baseline rates.

Alternative hypothesis: After receiving interventions through TPB, pica behavior rates will show a significant decrease compared to previous baseline rates.

Definition of Theoretical Constructs

The hypotheses were derived around the assumption that pica behavior is manifested in a person’s food-seeking intention.

This would provide the opportunity to utilize the Theory of Planned Behavior by planning more appropriate solutions to food-seeking intentions. Little information has been gathered around the specific use of this theory as it relates to pica behavior and interventions. Some suggestions offered by Stiegler (2005) about pica behavior interventions include:

  1. Safety is the most important factor.
  2. Medical staff should evaluate nutritional deficits.
  3. Early intervention is important.
  4. Consider the client’s quality of life when deciding on a treatment option.
  5. Involve a multi-disciplinary team.

Purpose of the Study

The purpose of this study is to apply TPB to pica behavior problems of individuals in institutionalized settings and to see how effective it can be to reduce the potentially harmful behavior of pica.

Rationale of the study

People who engage in pica behavior are usually those with developmental disabilities who may not be aware how dangerous pica behavior can be for them. Since it is not humane to always physically constrain them in order to prevent them from pica behavior engagement it is worthy to apply the Theory of Planned Behavior to help them manage their tendencies for pica. Should TPB be found effective, then it could be recommended to other settings where pica behavior is observed.

Significance and Limitations of the Study

The scientific contributions of this study would be to provide an intervention for pica behavior that is based on an already existing theory. If the null hypothesis is rejected, interventions can be assessed around intentions and environmental manipulations to satisfy those intentions in more appropriate and non-harmful ways.

The potential to create social change is such that pica behaviors can be reduced in all areas of the world. This would create a safer environment and would also aid in the education of pica treatments. In addition, this would expand the possibility of TPB being used in other areas of study with harmful or maladaptive behavior.

Limitations of this study would include generalizability. The use of a single case study has inherent limitations because conclusions are based on only one individual. Further research would need to be conducted to evaluate the potential for the results to generalize across settings, with different populations, and with other harmful behaviors.

Literature review

Pica concerns have been noted among human beings for many years. This behavior has particularly been of concern when working with people diagnosed with developmental disabilities (Albin, 1977). Danford and Huber (1981) noted that pica is the most frequent eating disorder observed in institutionalized adults with developmental disabilities. Albin noted that pica items could include various things, e.g. clothing, paper, trash, feces, or cigarette waste.

The Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) defines a pica as “the persistent eating of nonnutritive substances for at least one month” with the following diagnostic requirements:

  1. Persistent eating of non-nutritive substances for a period of at least one month.
  2. The eating of non-nutritive substances is inappropriate to the developmental level.
  3. The eating behavior is not part of a culturally sanctioned practice.
  4. If the eating behavior occurs exclusively during the course of another mental disorder (e.g. Mental Retardation, Pervasive Developmental Disorder, Schizophrenia), it is sufficiently severe to warrant independent clinical attention.

Kerwin & Berkowitz (1996) pointed out that pica behavior has been demonstrated in adults with developmental disabilities, as well as young children (age 3 and under) and pregnant women. DSM-IV stipulates that pica behavior must follow specific criteria including “The eating of non-nutritive substance is inappropriate to the developmental level” Ali (2001) stated that pica is considered to be a normal behavioral occurrence through the age of 18 months. This is a difficult stipulation in that many people with developmental disabilities who carry a diagnosis of pica are classified with a lower developmental level. A variety of items are consumed, e.g. cigarettes, clay, feces, dirt, paper and hair. The authors also supported the point that pica behavior can lead to serious medical complications or conditions, possibly even death. A very aged hypothesis- about pica behavior in developmentally disabled adults is the need or desire to mouth objects. Research on this topic is outdated and not current. No research has been specified since 1971. The function of pica behavior has focused on two domains: medical deficiencies or learned behaviors. The authors suggest that a functional assessment of behavior is necessary to establish the true function of behavior. There are multiple classes of pica identification based upon the specific item of choice for ingestion. Ali (2001) identified Coprophagia as the ingestion of feces and geophagia as the ingestion of clay, pagophagia as the ingestion of ice, and amylophagia as the ingestion of starch. Pica can be specific to a certain item or generalized to all non-food items as in the case of indiscriminate pica.

Pica behavior is found in greater numbers among people with more severe developmental disabilities (Ali, 2001). Pica rates are higher among institutionalized people versus people who reside in a community-based setting (Ali, 2001).

Theories on Etiology of Pica

Matson & Bamburg (1999) claim that past researches on the etiology of pica have been inconsistent and inconclusive. Albin (1977) reports that early explanations on the cause of pica point to arrested development as characterized by finger-feeding and the lack of the usage of utensils. Other researches explain pica as a result of gustatory reinforcement (Favell et al., 1982), deficits in social interactions (Mace & Knight, 1986), and biological deficiency in minerals (Lofts et al., 1990). Most of these theories are debatable however, there is consistent agreement that pica increases with the severity of mental retardation (Danford and Huber, 1982; McAlpine and Singh, 1986). This is especially true of those in institutional settings.

Some of the theories on the etiology of pica revolve around certain disciplines. They are as follows:

  1. Psychological Theories

One theory of etiology of pica is that people with intellectual disabilities are unable to discriminate between food and non-food substances (Bicknell, cited in Danford & Huber, 1982). Another theory claims that it is a form of aggression since an individual may resort to aggression when he is deprived of the pica item (Solyom et al., 1991). Still another theory proposes that the oral stimulation produced by pica is automatically maintained in the behavior (Bogart, Piersel and Gross, 1995). Pica is also believed to be greater in environments with reduced social interaction (Mace & Knight, 1986).

The formation of Pica habits has also been described as being due to social and cultural factors as well as to traumatic events that may have initiated psychological changes. This is a more holistic approach to the study of pica that attempts to examine more than just brain chemistry or biology, instead of requiring analysis of the conditions in the lives of Pica sufferers that somehow separate them from the sociological norm. Many sufferers of Pica have had traumatic or non-normative events such as parental separation or child abuse that has predated their Pica, and this could be a likely explanation of the sudden shift in behavior.

Arbiter and Black (1991) suggest that Pica is at least partially influenced by environmental factors. In their study, they found that between two different patients with radically different types of upbringing, the onset of pica was different. The first child received a relatively low degree of attention while the other child received negative attention primarily. In addition to the iron deficiency that both of the children had, the lack of attention was a contributing factor in their Pica symptoms. Additionally, it would appear that the inattention of exhausted parents who are already struggling with the child’s developmental disorder leads to further complications such as the development of pica (Arbiter & Black, 1991).

  1. Cultural theories

Pica, such as geophagia or the ingestion of clay has been explained as a culturally sanctioned behavior such as the seeking of mineral supplements of pregnant women or individuals needing detoxification. There are many cultures in which the development of Pica is actually a cultural norm and not something that is considered deviant in any way, such as in the state of Georgia in which many African American women eat certain kinds of soil (Grigsby, 1999). Reid (1992) reports cultural practices where the clay has been ingested as a traditional medical practice. In Ghana and Nigeria, clay has been used as a treatment for diarrhea, gastrointestinal parasitic infections, and pregnancy supplements. Such practice of clay ingestion for medicinal purposes may have influenced African American culture as it is still believed by many Africans that it is useful for the treatment of syphilis, dysentery, breast milk production, and facilitation of the birth process.

  1. Medical theories

Some medical beliefs that explain the cause of pica include mineral deficiency in one’s nutrition, neurological or neurotransmitter pathology, psychiatric disorders, and addiction to the pica substance (Ali, 2001).

There have been many attempts to explain Pica in terms of being the manifestation of various mineral and vitamin deficiencies within the human body. Rose (2000) claims that it is likely that Pica is caused when the body is knocked out of homeostasis due to the absence of a key nutrient, and that the desire to eat non-food items is compelled by the brain’s attempt to find that nutrient and to ingest it (Rose, 2000). There is evidence that the proportion of Pica sufferers who are also suffering from nutritive deficiencies caused by diseases such as celiac disease or a hookworm infection is relatively high, and this would be one possible explanation for the condition. However, Rose admits that there have been no studies that would suggest uncontrollable appetites for certain foods are controlled by the brain’s attempt to find certain nutrients, and the nutrient deficiency theory hardly explains why some Pica sufferers attempt to eat objects that clearly have no nutritive value.

Pica behavior is not found exclusively among people with developmental disabilities, and it is important to remember that the condition can have many different causes. Ward ‘s (1999) interviews of patients who had undergone dialysis for some time reported a higher than the normal incidence rate of pica behavior, and there were some interesting cultural variables to the reporting rate. For example, most of the patients who claimed to have some form of pica behavior were young African American women (Ward, 1999).

This data, along with that accumulated in other studies, might point to a higher likelihood that African American women will develop pica behavior in response to certain environmental stimuli. Additionally, the dialysis patients tended to eat a large deal of ice or starch, and this could have been due to the various blood levels of phosphorous and serum albumin. Due to the dialysis process, many micronutrients might have been lost by the body, and the pica behavior would have been an attempt for the body to compensate by eating unusual material. However, if this was the case, why did many of the patients choose ice, something with no nutritive value? Additionally, why was there a distinct cultural link between pica and African American women? The study found a number of physical predictors of pica behavior such as leg cramps but did not investigate the potential links between ethnicity and pica (Ward, 1999).

Diagnosis of Pica

The major difficulty in the diagnosis of Pica is that the current definition requires the eating of non-edible objects to be tied to disease. If the eating of the non-edible objects is in some way a response to a biological imperative (like a nutrient deficiency) then Pica is not a condition, but rather a symptom of an underlying biological condition. While animals do eat non-edible substances with relatively high frequency, it is unfortunately of only limited utility to study animal behavior in relation to Pica. Dogs tend to eat a large amount of concrete dust and sand, but this is not a result of mental imbalance but rather an instinctive reaction to a type of anemia in which the dog is attempting to consume certain macronutrients (Feldman, 2000). Clearly, animals and humans have some ability to detect when their nutrient balances are unstable, but this is not Pica behavior, rather an evolved biological mechanism that has been designed to increase the levels of deficient nutrients.

Additionally, the attempt at establishing the epidemiology of Pica is difficult, primarily because of the cultural variation in the normative food behavior. For example, there are cultures such as the aforementioned communities in Georgia, which do not self-report Pica as it has become part of their unique culture. This is also the case elsewhere, such as in Africa and in the Middle East. One of the tasks of the literature review will be to find populations in which the prevalence of Pica is particularly high, then to tie cultural and societal behaviors and factors to the prevalence of Pica in other populations as well. There have been numerous studies that suggest that Pica rates are high in both mental institutions (logically) but also in developing countries (Ngozi, 2008). This developing country’s connection suggests far more than just a superficial cultural connection of Pica to some externality, and it must be researched further.

Functions of Pica Behavior

Ali (2001) discussed various functions of pica. These proposed functions include medical causes, mineral deficiencies, nicotine addictions, and psychiatric disorders. Pica may be maintained by variables such as stress, anxiety and tension (Agarwala, & Bhandari, 1994).

Supporting the mineral deficiency theory cause of pica, it is believed that certain clays induced by individuals engaged in pica behavior have chelating properties, or the clay binds the mineral hence preventing its absorption (Ali, 2001). Danford, Smith and Huber (1982) found in their study that individuals with pica had lowered serum iron and serum zinc levels compared to individuals without pica. Danford and Huber (1982) then conclude that pica causes malabsorption of zinc and iron.

Complications of Pica Behavior

Kuhn and Matson (2002) discuss the possible risk of poisoning for people who engage in pica behavior. Having worked with a variety of populations, potential pica items can include dangerous and caustic items, e.g. bleach, paint, large doses of mouthwash, and gasoline. Albin (1977) stated that pica can include lead poisoning, intestinal blockages, parasite development, surgical intervention, or esophageal complications. In addition to the risk for lead toxicity and potential surgical requirements, Ali (2001) mentioned psychiatric difficulties and neurological complications as a result of pica behavior.

As Pica is very similar to obsessive disorder in the way that the sufferer is self-compelled to do destructive things, many psychologists have posited a link between OCD and obsessive eating. Cases of Pica are thus tied to the obsessive-compulsive spectrum, and there have been several attempts to explain Pica as being just one way in which OCD manifests itself. One leading neuro-psychopharmacologist believes that Pica is not deserving of its own disease, but that it is one of the many OCD spectrum disorders, and should be approached as other forms of OCD are (Herguner, 2008). However, currently, Pica is considered its own disease, and it is listed as a separate mental disorder in the canon of psychiatry, the Diagnostic and Statistical Manual of Mental Disorders.

Surgical complications or even death are usually the results of severe pica behavior, especially with toxic and harmful objects. McLoughlin (1988) gave the example of the death of one resident from a massive hematemesis caused by an esophageal tear due to a sharp bone that was lodged in the tear. This same resident has engaged in pica behavior all his life and already had several surgical interventions such as a thoracotomy to dislodge an inhaled screw and an esophagectomy to remove a plastic wheel.

Interventions for Pica Behavior

The growing prevalence of pica behaviors among patients with developmental disabilities has triggered the design of several interventions from various disciplines. Parry-Jones & Parry-Jones (1992) narrate that in the past, unusual treatments such as vomiting, purging, iron therapy, mineral baths, absinthe and oil figs, ingestion of difficult to digest foods, physical beatings, iron masks, and decapitations (to serve as an example to others who sustain their engagement in pica behavior) were applied to persons engaged in pica behavior. Such drastic procedures reflect the severity of the problem and the affected individuals’ resistance to treatments. As opposed to more intrusive and less humane treatments such as overcorrection time-out and restraint reported in the literature prior to the nineties, there is a current trend in the use of more reinforcement-based procedures. Some attempts to treat pica with psychoactive drugs or electronic convulsive shock have been successful when the psychiatric symptoms have cleared (Chatuvedi, 1988; Nissen and Haggag, 1987), but most therapies that predominate have been behavioral (Feldman, 1986; Foxx & Martin, 1975; Friedin & Johnson, 1979; Ghaziuddin & McDonald, 1985; Neale, 1963).

Interventions for pica behavior vary across authors, clinicians and settings. The following are interventions that have been studied and implemented over the years:

  1. Medical Model

As a medical condition, pica has been treated with medical procedures and medication in the belief that there are physiological disorders in the patient. Some examples are the following: Disappearance of pica in an 11-year old African American boy with compounding symptoms of hypersomnolence (oversleeping) and lead poisoning was reported upon the application of methylphenidate and chelation therapy (Boris et al, 1996). Another child, a 9 year, 5-month old girl diagnosed with severe mental retardation, iron deficiency and anemia, observed to engage in pica behavior, was employed the B-A-B experimental design using the multi-vitamin Polyvisol as the independent variable to reduce pica (Pace & Toyer, 2000). In the case of a 75-year old woman diagnosed with schizophrenia and a 20-year pica history of ingesting Dexedrine, Vitamin C, she was also assessed to mouth/ ingest tablets, coins, nuts, wire, plastic, “purple hearts”, Bob Martin’s dog conditioning powder and dried flowers. Beecroft, Bah, Tunstall and Howard (1988) reported that her treatment involved medical and cognitive-behavioral approaches with differential reinforcement of her consumption of Vitamin C. This reinforcement included the strategies of encouragement, persuasion, a constant supply of Vitamin C and controlling the environment to make it stress-free for her. This combination of interventions has proven to be partially successful.

Serum Zinc has also been used with mixed success on patients who exhibited some form of pica behavior as part of other associated mental illnesses. Institutionalized patients under the care of Ronald Lofts had about a 15% rate of pica behavior, and of that group, half had zinc levels that were below the normal range for people of their ages and body weights (Lofts, 1990). He hypothesized that the low levels of zinc were triggering a response by the body to ingest foreign material and that the replacement of the zinc levels would lead to a lower occurrence of pica behavior. While the replacement of the zinc did, in fact, decrease the amount of pica behavior, it did not eliminate it in any of the patients. This lends credence to the theory that Pica is a biological response of the body that has been evolved over time as a response to nutrient deficiency. However, nutrient supplementation must be attended with other psychological therapy in order to minimize the occurrence of pica, perhaps replacement therapy in order to rid the patient of the positive associations with eating non-food items.

Additional pharmaceutically-based interventions have also been tried in an attempt to modify the chemical balance in the brain to make pica behavior less likely. In clinical trials, one drug that seems fairly promising is Olanzapine, a common psychiatric medication that has suppressed pica behavior in both studies and in institutional use. According to the medical professional that was in charge of the study, Dr. Lerner, the use of the olanzapine helped counter some of the lobe damage of the specific patient. He claims that the patient’s pica behavior was significantly reduced by the drug, Olanzapine which is an antipsychotic drug with powerful effects on dopaminergic, serotoninergic, adrenergic and cholinergic systems (Lerner, 2007). However, Lerner still admits that this use might be very specific to the individual in question and that the explanations for pica behavior were very individualized and defied a single treatment model.

  1. Cognitive Model

Effects of self-monitoring alone and self-monitoring with progressive relaxation was tried out with subjects (four boys and four girls aged 15-17) with normal intelligence. Both treatments were effective in significantly reducing pica behavior during treatment, however, the addition of progressive relaxation helped in maintaining the absence of pica during follow-up probes. It was believed that progressive relaxation helped in reducing anxiety which was an associate characteristic of pica (Bhandari and Agarwala, 1996).

One intervention strategy with promise in a normalized setting is that of a pica exchange program (Goh et al., 1995). A pica exchange program works by shifting the attitude of the patient so that they replace the pica material with something that is less harmful. In a pica exchange program, the intrinsic value that the patient places on the ingested material must be discovered and analyzed, and that value must be applied to another type of material in a more healthy way. This intervention, however, runs the risk of increasing the tendency for the patient to actively search and scan for pica items, although the program’s effectiveness can be increased by following two general rules. The exchange item must have a positive reinforcement attached to it which convinces the patient to switch from the pica item to the new item, and the pica behavior must have an underlying psychological cause such as hunger, some desire that is being filled by the eating behavior. In situations where the pica behavior is driven by some non-social or sensory stimulation, the attempt to use an exchange program will probably fail. Psychologists use pica-preference programs to determine what kind of value a patient attaches to various items of differing natures.

An example is Baker et al.’s (2005) study of a 40-year old man with profound mental retardation who engaged in coprophagy. The functional assessment indicated that the pica was self-reinforcing behavior in his case, and for the individual, the taste and smell of his fecal matter are self-stimulating. A competing or replacement behavior was targeted with the introduction of highly spiced, flavorful food, hoping he would engage in ingesting it instead of feces. The spicy food was given to the patient with each meal and was freely accessible to the individual any time he wished. He seemed to enjoy the spicy food but also had access to non-spicy food. His coprophagy dramatically decreased for 6 months.

Matson & Bamburg (1999) identify the two most frequent disorders as a stereotypic movement disorder and autistic disorder, both of which are characterized by deficiencies in social skills and a lack of appropriate environmental stimulation. Being aware of such helps the therapist in using treatments that also teach appropriate social skills and enhance environment stimulation which is conducive in the provision of alternative or replacement behaviors. When a patient with a history of pica receives such treatment that enhances those skills, it becomes possible to replace the pica behavior with more goal-directed, socially appropriate behaviors. These more socially acceptable behaviors also compete with the nonsocial tendencies often associated with pica in individuals with mental retardation. In order to remedy such antisocial behaviors, such individuals may be trained for social skill development (e.g. peer interaction) and functional communication along with the interventions that aim to decrease pica (Johnson et al., 1994). Social skills training has also been effective in decreasing behavior problems in other forms of psychopathology (Bellack et al., 1983).

  1. Behavioral Model

Behavioral interventions are most commonly used in behavioral disorders such as pica. Agarwala & Bhandari (1994) noted that behavior intervention techniques are able to demonstrate the highest degree of success with pica occurrence at near-zero rates. Historical behavioral interventions have included time-outs, overcorrection, evaluation and screening, contracting, and physical restraint. Albin (1977) also add that intervention suggestions have included establishing specific non-nutritive items within the environment to “bait” the client for attempted ingestion, time out from specific locations, physical restraint techniques to prevent the behavior, or positive reinforcement of alternative behaviors.

A behavioral assessment is required to identify individuals who swallow objects in response to hallucinations, delusions, or in reaction to mood or anxiety symptoms. Once there is reasonable certainty that there are no medical explanations for the Pica, an assessment of psychiatric symptoms should be conducted. Individuals with intellectual disabilities are more likely to have behavioral manifestations of psychiatric symptoms when they occur and are less likely to be able to verbalize in a sophisticated way about what they are experiencing. Some assessment tools designed for aiding the identification of psychiatric symptoms in individuals with intellectual disabilities include the DASH-II (Diagnostic Assessment for the Severely Handicapped-II), the ADD (Assessment of Dual Diagnosis), and the REISS Screen. These instruments have taken symptoms for the various diagnostic categories in the DSM and translated them into descriptions of behaviors that have been associated with particular diagnostic categories. This kind of assessment can also help sort out which behaviors are manifestations of a psychiatric disorder and which behaviors are results of learning. Functional behavioral assessments need to be conducted for the latter when identified. This provides evidence of underlying medical conditions, social interaction difficulties, or discrimination problems (between edible and non-edible items). The last one may also be interpreted as a cognitive dissonance issue that may be addressed by cognitive models.

A strategy of negative reinforcement has been tried by numerous studies, including one by Rojahn (1987) in which a patient was treated with both water mist and with aromatic ammonia in order to create a negative association with pica behavior. In this study, every time the adolescent would engage in pica behavior, he was sprayed from a mister or he was exposed to ammonia. In the water misting program, the development of a negative association with pica was rapid, and the adolescent quickly learned to minimize that behavior in order to avoid the negative stimulus. The response to the aromatic ammonia was slower, and the patient had only a small response until the amount of ammonia was greatly increased. The complete suppression of the pica behavior due to the water mist should not be confused with the treatment, however. It is likely that in the absence of the negative stimulus for an extended period of time, the adolescent would relearn the pica behaviors, perhaps with a new item. According to the study, the adolescent was taught that a specific item (clay) was not edible, but that the negative association did not necessarily carry over to other pica items.

Hagopian and Adelinis (2001) identify response blocking as a method of intervention to prevent the occurrence of pica behavior. While response blocking does not decrease one’s attempt at pica behavior, it does drastically reduce the risk of ingesting what may lead to major medical complications. Hagopian and Adelinis theorized that response blocking may lead to an increase in aggressive behavior that possibly would lead to an increased risk of injury to staff or clients. Through observation of response blocking behavior in the presence of baited and potential pica items, the authors were able to assess changes in rates of aggression related to the response blocking. The study demonstrated an increase in aggression. Aggression may have increased for multiple reasons: First, is blocked access to desired items fuels one’s desire to get to that item, thus, triggering aggression. Another reason is past reinforcement for immediate access to pica items upon exhibition of aggressive behavior. The authors did not find that adding a verbal prompt to redirect behavior resulted in a lesser rate of aggressive behavior.

Aversion therapy was done on a subject who exhibited coprophagia or ingesting or mouthing feces (Foxx & Martin, 1975). The oral hygiene over-correction procedure was implemented which required the subject to brush teeth, gums, and tongue with a toothbrush soaked in oral antiseptic each time the subject was observed to eat feces. The subject was likewise required to expel the feces by spitting it out or coughing it. On top of that, the subject needed to wash their hands extensively and to get rid of the debris by throwing it out of the wastebasket and ashtrays after the pica behavior has transpired.

Differential reinforcement of alternative behavior (DRA) with brief time-out was found to be an effective treatment for pica. Evidence of this was from the study of Northrup et al. (1997) wherein a 35-year old woman with severe mental retardation engaged in pica behavior, putting inedible objects such as paper, plastic, or smoking-related material in her mouth. Using the DRA/ time-out intervention resulted in maintaining low levels of pica even with only 50% implementation of time-out.

  1. Environmental Control

Pica interventions are twofold, in that they must correct the pica behavior in the long run while also ensuring that the behavior does not cause further medical complications. In situations where the patient is eating primarily non-toxic material, the treatment program can focus on organic negative and positive reinforcement, allowing the patient to gradually break the habit. This type of intervention is the most successful at actually ridding the patient of the desire to eat the foreign material. However, in many situations, such a gradual approach to pica behavior is impossible. In situations where the pica behavior poses a definite health threat, such as the consumption of bleach or batteries, it is often necessary to remove the offending material from the environment and deny the patient access to the pica material. In these cases, the underlying psychological condition is not treated because it is judged too dangerous to allow the patient to continue their behavior for any reason. Strict environmental controls are able to eliminate pica behavior but they only work for as long as the controls are in place. Additionally, such strict controls only work for as long as the controls are in place. Additionally, such strict controls only work in the institutional environment in which every environmental variable can be controlled, and it is impossible to apply such a strategy to a community or normalized setting.

Strict environmental control can exacerbate other conditions if it is not handled appropriately. In institutions where there is not enough staff ratio, patients may have their ability to move freely greatly restricted in order to prevent their access to pica material. This can limit their other behavior, and it can limit their overall growth in the program. Conversely, it is necessary to strike a privacy vs. treatment balance, especially in adult patients in order to convince them of the importance of continued treatment.

On the other hand, having less restrictive interventions are getting to be the trend nowadays, perhaps due to the more widespread use of functional assessment procedures which are less time-intensive. However, these less restrictive treatments may also be slower to develop because of difficulties encountered with behaviors maintained by automatic reinforcement (Tracy, de Leon, Ghayyur, McCann, McGrory & Josiassen, 1996; Swift et al., 1999).

  1. Combination of Models

Patients who develop Pica in response to distressing psychiatric symptoms also require behavioral interventions. Behavior analytic procedures can be included with other treatment modalities for a person who has both psychiatric diagnosis and intellectual disabilities. Behavioral specialists can determine appropriate training strategies to assist a person with intellectual disabilities to gain better-coping skills for dealing with their psychiatric symptoms. Triggers for the symptoms can be identified and strategies are taught to staff, family members, and the individual to prevent escalation of the behavior symptom. Counseling can be provided, keeping in mind that discussions need to be geared toward the level of understanding of the individual. Most counseling should take the form of skill-building and include the chance for positive, enhancing environment reinforcement that “completes” the behavior during the learning process, e.g., daily scheduled nutritional snacks, free access to food items, etc. For example, if an individual becomes angry easily due to an impulse control problem, anger management training may be successful when presented in simplistic terms, modeled by the clinician, and practiced repeatedly by the individual in more than one or two sessions. As the person learns the management techniques, positive reinforcement should be delivered to assist with the acquisition and maintenance of the skills.

Vollmer (1994) suggested that an evaluation of specific sources of reinforcement, as well as incorporation of other indirect methods indicating correlational relationships, are usually included in current assessment forms of pica. With less use of intrusive interventions involving the manipulation of environmental variables, such assessment and interventions are becoming more popular in the treatment of this disorder.

Intervention Difficulties

Albin (1977) pointed out difficulties with intervention as difficulty associated with generalizing across settings, cost of staffing ratios, and time-consuming efforts. Some of the previous attempts at Pica intervention have used rather ineffective methods due to the association of Pica with a lack of understanding of what is and is not a food item. However, as the prevalence of Pica among adults and in other cultures suggests, pica does not necessarily imply a misunderstanding of what should be considered a food, rather it shows a different value system that is not weighted as strongly in favour of eating food items. In one treatment program, Ausman et al (1974) attempted to treat an adolescent with profound retardation who was eating non-food items. They believed that this refusal could have been due to both a biological hunger (the child was missing meals frequently) as well as a misunderstanding of what was food (Ausman et al., 1974). They attempted to intervene using two different strategies, including the placing of food on the floor in the place of non-edible material and the creation of negative reinforcement. While the negative reinforcement makes sense under the framework of attitude change, the attempts to make regular food more available does not. Someone that is afflicted with Pica is not eating various items because there is no food available, rather they have an attitude in which they assign more value to eat the non-food items. Simply taking away those items will not solve the underlying problem of Pica, even as it manages the symptoms.

Not all treatment and intervention programs are specifically targeted at reducing the occurrences of Pica behavior, some are targeted only at reducing the harm that such behavior can cause. For those who believe that Pica is not its own condition, but is a symptom of some kind of developmental disability, pica is not treated separately. This type of intervention, such as response blocking, is proposed by Hagopian and Adelinis (2001). The use of response blocking only serves to limit the ability of an individual to ingest potentially harmful and caustic substances, but it creates another psychological problem in that the patient still has the motivation to eat the substance but is being physically prevented. As there is no attitude change, the patient is frustrated and takes out anger either on the workers at the facility or on themselves. Aggression increases when the potential pica items are taken away, implying that response blocking is not making any difference in the behavior itself, rather it is just making the behavior impossible for a temporary period. The authors believed that the attempt to use only response blocking was not a good idea, as it increased the likelihood of self-harm, but that response blocking needed to be combined with some kind of attitude-changing strategy such as the use of verbal prompts (Hagopian & Adelinis, 2001).

In one study, patients were led through a variety of treatments for pica. While the intervention was ultimately successful, the fact that there were three different treatment programs in places simultaneously makes it difficult to pick out which one was the effective component, or whether all were necessary. Madden (1981) dealt with children who had developed lead poisoning as a result of pica behavior, causing additional permanent neurological damage and making it difficult for the care providers to separate the lead poisoning damage from any of the pre-existing behaviors. Three procedures were used to change the attitudes of the people with pica behavior. For one, the patients were trained to discriminate between edible and non-edible objects (Madden, 1981). This had the purpose of reinforcing societal boundaries and teaching the patients that their behavior was not normative. Next, each patient was given positive reinforcement when they did not eat pica despite its existence in the area, and they were overcorrected should they eat the pica. Progressively, the attitudes of the patients changed towards the pica and they stopped considering it a dietary component. This shows the importance of holistic treatment of the condition, although there was no attempt to discover the conditions underlying the root cause in order to prevent future outbreaks. Additionally, using a strategy that focuses on negative or positive reinforcement has the danger of only causing one type of pica material to undergo a change in attitude, while still leaving the underlying behavior.

Beecroft et al. (1998) conducted an interesting study on a case of pica that manifested itself in a very interesting way and may point to the roots of pica as being similar to those of addictive behavior. The 43-year old female in question was constantly taking high doses of Dexedrine, enough that she developed a psychological reliance on the drug and an association of her feelings with the pills themselves. Additionally, she was taking large doses of vitamin C, also in pill form, as a self-treatment for anxiety. Both the Dexedrine and the vitamin C were creating a powerful association in her mind of pills with her feelings and her moods. Later on, the interview discovered that the patient had a history of pica in which she would ingest coins and other items as a way of regulating her anxiety level. Clearly, the patient had graduated from items such as plastic to tablets, and as the availability of drugs increased with her age and her income, she began to take pills in the same way that she previously had ingested foreign objects. The patient had a psychological connection between feeling good and ingesting small items, and this clearly escalated along with the availability of pharmaceuticals which are already marketed as being capable of mood changing. From the perspective of behavior analysis, this behavior has a clear connotation with addictive behavior and with possible frontotemporal atrophy leading to swallowing behavior and with a hyperoral fixation (Beecroft et al, 1998).

Theory of Planned Behavior

In 1985, Icek Ajzen conceptualized the Theory of Planned Behavior (TPB), which predicts one’s behavior based on his beliefs. These beliefs fall into three categories: behavioral beliefs or the positive or negative outcomes of their behavior; normative beliefs or the normal expectations of society; and control beliefs or the presence of factors that may facilitate or hinder behaviors (Ajzen, 1985). To illustrate, an individual may believe that having a healthy diet will bring positive outcomes for his body, so he must make an effort to prepare healthy meals (behavioral belief). The people around him as well as what he sees on television and the news support this belief that healthy eating is beneficial (normative belief). However, time and money constraints can prevent one from preparing healthy meals (control belief).

In its totality, behavioral beliefs produce the kind of attitude toward the behavior. It leads the individual to anticipate or avoid it. Normative beliefs determine the individual’s perceived social pressure or subjective norm to either engage in the behavior or not. Control beliefs give rise to an individual’s self-efficacy with regards to the behavior, and if he can hurdle the control factors or not in order to engage in the behavior. Taken together, one’s attitude toward the behavior, the perceived subjective norm, and control factors form the individual’s determinants of intention. This intention is strengthened if the attitude and subjective norm are favorable and there is greater perceived behavioral control. Such intention is carried out upon the availability of an appropriate opportunity. The successful performance of the behavior does not merely depend on one’s favorable intention but also on his or her volitional control. This entails the skills, resources, opportunities and presence of other conditions that are supportive of the behavior (Ajzen, 1985).

The TPB can be perceived to be additional behavioral control in the prediction of behavior. If the perceived behavioral control is accurate and together with intention, it can be used to predict behavior (Ajzen, 1985). For example, if the intent is to be healthy by eating more healthy meals, the behavior control should be the availability and accessibility of healthy food. The theory of planned behavior already predicts that such a contrived situation would result in successful behavior which is healthy eating.

A person’s beliefs are well considered in TPB especially salient ones that easily surface during free-response settings. A representative sample of respondents may be asked to enumerate the pros and cons of engaging in a certain behavior (behavioral beliefs); to list down people who may approve or disapprove of such behavior (normative beliefs) or cite factors that may facilitate or inhibit the performance of the behavior (control belief). Of course, there are other factors such as personality, gender, level of education attained, intelligence, motivation, or other values that may be assumed to influence one’s behavior but Ajzen (1985) believes these factors only indirectly affect the salient beliefs upheld by the individual.

If TPB is to be successful, the measures of the individual’s attitude, subjective norm, and perceived behavioral control plus the intention to do the behavior should all be compatible with one another as well as with the measure of behavior that is relative to the action involved, the target of the action and the context and time of the behavior’s performance. Also, the individual’s attitude, subjective norm, perceived behavioral control and intention must remain stable over a period of time. This is essential because any change no matter how slight may impair the predictive validity of the TPB.

In relation to the theory of planned behavior, the theory of reasoned action studies the factors that make a person behave in a certain way at his own volition. The behavior is under the individual’s control, whereas in the theory of planned behavior, behavior is studied in the context of variables over which the individual has no complete control of (Wellbourne, 2007). The theory of reasoned action was conceptualized by Martin Fishbein and Icek Ajzen to determine factors that affect behavioral decisions that are volitional or under an individual’s control. The theory of planned behavior asserts that if one has less volition to perform a behavior, then it is necessary to consider the degree to which other factors either hinder or facilitate his ability to engage in it. This determinant of behavior may be referred to as perceived control which can be added to the components of attitude, subjective norm, and intention in the performance of a behavior. It follows that if the individual perceives greater control of the variables and the situation, there is also a greater likelihood to engage in the behavior. On the other hand, the lesser the perceived control is, the lesser the likelihood to perform the behavior (Wellbourne, 2007).

In sum, the theory of planned behavior claims that attitudes, subjective norms, and perceived control interplay to influence an individual’s intentions to perform a behavior. It differs from the theory of reasoned action because it studies the role of perceived control in the performance of a behavior. TPB then is more applicable to a wider array of behaviors that are not fully under the control of the individual. In TPB, both intentions and perceived control directly affect the performance of a behavior (Wellbourne, 2007).

Ajzen’s Theory of Planned Behavior is not free from criticisms from other scholars. One questioned the theory’s sufficiency to predict intention and behavior. Apart from the attitudes, subjective norms, and perceptions of behavior control, some critics suggest the addition of other variables such as “desire, need, affect, anticipated regret, personal and moral norms, past behavior, and self-identity” (Ajzen, 1985, p. 989). This includes the extent to which an individual sees himself capable of performing the behavior.

Ajzen (1985) also cites another criticism of his theory wherein its reasoned action assumption represents only a single mode of operation which is the controlled or deliberate mode. He claims that Russell Fazio’s MODE model is designed in a way that reasoned action happens when individuals are motivated and capable of claiming their beliefs, attitudes, and intentions by working hard for it. If motivation or cognitive capacity is lacking, they rely on spontaneous actions wherein attitudes must be strong enough to be automatically activated in order to guide behaviour.

Still another critique of TPB, as shared by Ajzen (1985) is that reasoned action may become automatic after some time. When that happens, the behavior no longer requires conscious control in order to be executed. The control now is transferred from conscious intentions to mere stimulus cues. Also, the fact that the behavior may have been performed so often makes it a good predictor of later behavior. It becomes more credible than intention and perceived behavior control (Ajzen, 1985).

Research method

This study attempts to use Ajzen’s Theory of Planned Behavior (TPB) as the framework to reduce or at best, extinguish pica behavior in an individual with developmental disability. It will employ an intervention based on TPB on a selected subject from a residential facility for adults with developmental disabilities. To gather baseline data on pica behavior, it would involve a quantitative research strategy. Such strategy would be to examine the availability of food, times, and food preferences. The reason for evaluating this is to assess if hunger (or issues relating to taste preference) have an impact on pica attempts and pica incidents. The addition of a study on pica behavior will help to identify if food choice contributes to pica behavior and will assist in examining potential hunger issues. The gathering of baseline information is estimated to take two weeks.

The quantitative research strategy would be to evaluate the number of pica attempts or successful pica incidents across time. Occurrence rates of attempts/ successful engagement of pica behavior shall be recorded on a data sheet for evaluation. The reason for evaluating this is to look at increase, decrease, or maintenance of rates upon the administration of interventions designed along the lines of Theory of Planned Behavior.

Collection of Baseline Data

Information regarding history of pica behavior of the selected subject should be provided by the residential facility to the researcher so that the pica item preferred can be identified. The pica item/ items should first be placed in a “Skinner box” contraption which has four boxed sections that are covered with clear plexiglass with the covers securely screwed on. In each of the sections, provide either a food item or a non-food item (i.e. cigarette butt, juice carton, candy bar, nuts and bolts, etc.). Baseline information is validated when the subject chooses his or her preference when asked to pick one.

During the baseline period, 2 Skinner boxes will be left outside the dining area situated on the opposite sides of the room. One box will contain real snack foods (ex. Popcorn) with the lid of the box open so it is freely accessible to the subject. On the other side of the room is the box containing the preferred pica item. The box is locked, but the key is visible nearby, hung on a hook on the wall. Every day, for a week, the subject will be led to a table in the middle of the dining room to sit down. He/She will be observed as to behaviors towards the boxes. On the orientation day, the subject will be free to explore the boxes without touching it. On the following days, the subject will be left to be observed within the hour allotted for the study.

Measures of Variables

Heiman (2002) claimed that a variable should be a measurable aspect of a behavior that may change, and it is this that produces the scores and data of a study. For this study, the variables to be measured are intention exhibited by the subject and the behaviors of pica engagement and eating of real food.

Intention is measured by the direction the subject will take. Intention to engage in pica behavior is measured when the subject goes to the pica box and attempts to open it with the key. Intention to eat real food is measured when the subject approaches the food box and touches the food inside.

Pica behavior is measured by successfully opening the lock of the pica box, picking up the pica item and putting it in towards the lips. Mouthing, nibbling, licking and ingesting the pica item is scored as pica behavior on the observation sheet. On the other hand, eating real food is measured by successfully picking up the food item in the food box and eating it.

The observer will note in the observation sheets the number of times intention to engage in pica behavior and the number of times intention to eat real food are observed within the hour. Pica behavior and eating real food behaviors will also be noted if these are successfully achieved after some intended attempts. Data will be noted in the following chart:

Pica Box Food Box
Baseline Data # of intended attempts # of successful pica behaviors # of intended attempts # of successful food-eating behaviors
Day 1
Day 2
Day 3
Day 4
Day 5

Table 1 Observation Chart for Baseline Information of Pica Behavior

Percentage of Pica Behavior During Baseline Period The data recorded on this observation sheet will determine the baseline percentage of pica behavior vs. eating real food behavior by dividing the # of successful observed behaviors with the number of intended attempts multiplied by 100.

# of successful pica behaviors x 100 =

# of intended attempts

Percentage of Eating Real Food Behavior During Baseline Period

# of successful eating real food behaviors x 100 =

# of intended attempts

These percentages will be averaged to determine the subject’s baseline information for 5 days.

Upon establishment of baseline data about the pica behavior of the subject, the intervention phase will commence.

TPB as Intervention

Based on the Theory of Planned Behavior, an individual is likely to perform a certain behavior if the factors of behavioral, normative and control beliefs all complement to facilitate the behavior. If the goal is to reduce/extinguish pica behavior in the subject, then, these beliefs must be reconstructed to discourage the individual from engaging in pica behavior. Thus, the following beliefs must be learned by the subject:

  1. Behavioral belief: It should be inculcated to the subject that eating real food is beneficial to one’s health because it feeds nutrients to the body to keep it going. Eating non-food items such as the pica items he or she prefers to eat will only result in negative outcomes. Examples of these are blockages in the esophagus and other body organs which may result in tears, poisoning, bacterial infections and other diseases that may be damaging to the individual and even cause his or her death. This explanation should be delivered to the subject in a manner understandable to him or her. It should be convincing enough to make the subject believe that eating real food is what he or she needs while eating pica items will be detrimental for him or her.
  2. Normative belief: The subject should be made to understand that in the residential facility, everyone should eat real food and eating non-food items are frowned upon. This may be supplemented by exposure to television shows or videos about healthy eating. If videos or documentaries about pica are available, then these should also be viewed by the subject to make him understand the dangers of the behavior from an objective point of view. The staff and other residents should also be observed by the subject to be eating real food and as much as possible, he or she must not be exposed to co-residents who engage in pica behavior or else, the normative belief of everyone eating real food will be weakened.
  3. Control belief: The environmental factors around the subject will be contrived to make pica items undesirable and not as readily accessible as real food items. This will make the subject believe that it will be difficult for him or her to get to the pica items and since real food items are available, then it is more likely that he or she will contend with eating the food items instead of the pica items.

The conditions for the intervention phase should remain consistent all throughout. This means that the behavioral beliefs should be cultivated with the feeding of information about the benefits of eating real, healthy food and the dire consequences of eating pica items. Graphic posters can be placed in several visible areas about eating real healthy foods. Pictures of delectable foods should be included in the poster to entice the subject to eat food and distract him or her from the urge to eat pica items. Staff as well as other residents should be seen enjoying good, healthy food to strengthen normative beliefs. Pica items identified to be preferred by the subject should be disposed of and access to real food should be available to the subject instead. This would strengthen control beliefs.

Design of the Study

According to Heiman (2002), descriptive designs are used to demonstrate a relationship, predict behaviors and describe a behavior or participant. This study may be considered exploratory and descriptive since it explores the practical application of the theory of planned behavior as an intervention to reduce or extinguish pica behavior. It is also descriptive in that it observes the behaviors of the subject and then describes how such behaviors may relate to the intervention used. This study will evaluate the effects of environmental manipulations on the presentation of pica behavior or attempts of a single subject. From this single case study, the researcher will determine the success of the theory of planned behavior as an intervention.

Sample and Population

In a selected residential facility for adults with developmental disabilities, residents who have been observed to engage in pica behavior within the past month will be identified. Among these residents, one will be selected based on his or her capacity to think and behave based on behavioral beliefs, normative beliefs and control beliefs as described by Ajzen in his theory of planned behavior. Hence, although the residents all have developmental disabilities, the selected subject should be able to comprehend on his or her beliefs and act accordingly on them, as certain variables in the environment will be manipulated in the research study in order to influence such beliefs. Therefore, the subject should not be profoundly developmentally disabled but have enough understanding of his own behaviors’ consequences (behavioral beliefs), the expectation of others (normative beliefs) and the presence of factors that may encourage or discourage some of his or her behaviors (control beliefs). Data about the identified residents engaging in pica behavior will be furnished by the residential facility and they can screen the possible resident to be selected for the case study based on the degree of developmental disability possessed.


Before commencing the study, permission should be sought with the institution where the prospective subject resides. A letter of intent will be sent disclosing the purpose of the study and the need for approval to conduct the study in the residential facility (See Appendix A). Apart from the institution, another letter is addressed to the family of the subject seeking permission for their family member to participate in the study in the hopes of finding an effective treatment for his/her pica disorder (See Appendix B).

This study will have a single subject to observe. A baseline measure of pica rates will be gathered from data for the past six months. A week prior to the intervention, baseline data will determine which particular non-food item is considered the preferred pica item of the subject as well as the percentage the subject engages in pica and in eating real food during the observed time of an hour each day for five days.

Data Collection

Phase 1, Baseline Phase: The subject will be evaluated for any pica attempts or pica successes as observed by the researcher for an assigned hour per day for five days. This phase has been explained above including the use of the observation sheet on Table 1.

Phase 2, Intervention Phase: After gathering information on pica behavior of the subject for five days, the proposed intervention of Theory of Planned Behavior by Ajzen will be implemented with the collaboration of the staff of the institution. The subject will be educated about the advantages of eating healthy foods and the disadvantages of eating non-food items. This will be explained by the researcher using visual aids and a video documentary, if available. This session will be given on the first day of the intervention phase and every week thereafter for four weeks. Posters on healthy eating will be seen all around.

Staff will also be trained to display positive behavior towards eating healthy food. The pica item will be viewed as a negative object that needs to be disposed of. The food and pica boxes from the baseline phase will remain in their places in the dining hall with the same conditions: the open food box will contain easy to eat snacks such as popcorn, raisings, nuts, fruit slices, etc. This box will be on one end of the dining area. Opposite to the food box is the sealed pica box containing the pica item. The key to the lock of this pica box is hung on a hook on the wall nearby, however, it is higher to reach than in the baseline phase. This is to make it more difficult to access the key thereby lessening the control of the subject on performing the pica behavior. It is to be ensured that no pica item will be available anywhere around the environment except for the one in the Pica box.

During this intervention period, the subject will also be observed every day for an hour by the researcher to record observations of intended attempts and successful pica behaviors and eating real food behaviors on another observation sheet similar to Table 1. However, the intervention will run for four weeks. Again, the percentages of successful pica behaviors and the percentages of successful real food-eating behaviors will be computed over the span of four weeks.

Rate of pica behavior during the baseline period and during the intervention period will be compared to see if there is a decrease, increase or no change due to the intervention of TPB.

Analysis and Potential Confounding Variables

Data gathered will be frequency counts during the observation periods for the baseline and the intervention phases. These will be computed as to the percentage of engaging in eating real food behavior and percentage in engaging in pica behavior. The data will be analyzed according to the subject’s responses to the intervention, taking into consideration factors that may facilitate or confound the results.

Cozby (2007) suggests the likely possibility that it is the extraneous variables that may be causing an observed relationship. This is called the confounding variable. A possible confounding variable is the developmental disability of the subject. The delivery of information meant to influence the subject’s behavioral beliefs regarding eating healthy foods and the disadvantages of engaging in pica behaviors may not be received by the subject as expected. Since the subject has developmental disabilities, there is a risk of miscommunication or failure of fully comprehending the information. Another confounding variable may be the inhibitions of the staff when showing positive behaviors towards eating healthy foods and negative behaviors with pica items. This is meant to strengthen normative beliefs, and the staff should be trained well to endorse the behavior of eating good food if not, it may confuse the subject in the formation of his/her normative beliefs.

Ethical Considerations

This study aims to comply with ethical standards and considerations in conducting research with human participants. The necessary forms will be completed, as well as necessary permissions, sought, in relation to the recruitment of participants well as the conduct of the interviews. Confidentiality of information will be ensured so that the trust of the subject and his/her family will be established.

Special considerations will be undertaken with regards to the subject since he/she has a developmental disability. For example, the food to be put in the food box, and the pica item to be put in the pica box will not pose to be a danger to the subject during the study. Allergies of the subject will be determined prior to the study so foods he/she is allergic to will not be used. Also, the pica item will not be ingested by the subject at least under the watchful eye of the researcher. Utmost care will be ensured to protect the rights and safety of the subject so that his/her well-being is top priority. Participation is non-obligatory and at the risk of loss for this study, the subject may withdraw anytime he/she may feel unease in his/her participation in this study.


  1. Cozby, P.C. (2007) Methods in Behavioral Research, 9th edition, McGraw Hill
  2. Freud, S. (1964) New introductory lectures on psycho-analysis. In J. Strachey (Ed.), The standard edition of the complete works of Sigmund Freud (Vol. 22, pp. 1- 182). London: Hogarth and the Institute of Psychoanalysis. (Original work published 1933).
  3. Heiman, G.W. (2002), Research Methods in Psychology, Third edition, Houghton Mifflin Co.

Appendix A. Letter of Intent to Conduct Study in an Institution




Dear Sir/Madam:

Good Day! I am Donna I. Litteral, a doctoral candidate for Psychology at the Walden University. I am currently doing a study entitled “Exploring the Theory of Planned Behavior as an Intervention for Correcting Pica Behaviorfor my dissertation. My research aim is to explore the Theory of Planned Behavior as an intervention for reducing or extinguishing Pica disorders. Hopefully, my research will be of significance to individuals suffering from such disorders.

In view of the above, I am seeking your permission to allow me to conduct my study in your institution with one chosen subject observed engaging in pica behaviors. I will be observing the behaviors of that individual for an hour each day for five weeks. I shall set up the environment to establish some beliefs in him/her that eating real food is beneficial and engaging in Pica behavior is damaging. For that, I would need the cooperation of your staff. I can explain the framework of this study to you at your convenience.

Please be assured that with your permission to conduct the study, the selected subject will be accorded with the utmost respect and consideration.

Thank you and hope to hear from you soon!

Sincerely yours,

Donna I. Litteral

Appendix B. Letter to Parents/Family Members Consent Form

Dear _______(name of parents or guardian),

I am Donna I. Litteral, a doctoral candidate working on my dissertation entitled “Exploring the Theory of Planned Behavior as an Intervention for Correcting Pica Behavior”. This study hopes to find an effective treatment/intervention for the Pica disorder which is the tendency of an individual to mouth or ingest non-food items. Such behaviors may cause negative outcomes for the individual.

In this regard, I am seeking your permission to allow your family member, _____________(name of subject) to participate in my study by way of being observed of his/her behaviors toward food and non-food items that he/she prefers to put in the mouth or ingest. I understand that he/she is a resident at the ___________ (name of institution) and has exhibited pica disorders for some time now. Should you grant permission for his/her participation in this study, he/she will be observed for an hour everyday for 5 weeks, the whole duration of my data gathering stage of my dissertation. This will include the baseline stage of determining the extent of his/her pica disorder as well as the intervention itself, the application of the Theory of Planned Behavior.

Please fill out the attached consent form to signify whether you give your family member your permission to participate in this study and return the form to the institution.


Donna I. Litteral

Consent Form

I understand that my family member’s participation in this study is entirely voluntary and that I may refuse permission for him/her to participate.

_____________ I consent to my family member’s participation in this study.

_____________ I do not consent to my family member’s participation in this study.

__________________________ _____________________________

Subject’s Name




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