Differential reinforcement of high rate behavior to increase the pace ...

Behavioral InterventionsBehav. Intervent. 24: 17–22 (2009)Published online 16 December 2008 in Wiley InterScience(www.interscience.wiley.com) DOI: 10.1002/bin.273DIFFERENTIAL REINFORCEMENT OF HIGH RATEBEHAVIOR TO INCREASE THE PACE OF SELF-FEEDINGKelli M. Girolami 1 , SungWoo Kahng 2 *, Kellie A. Hilker 3 and Peter A. Girolami 31 Kennedy Krieger Institute, the University of Maryland, Baltimore County, USA2 Kennedy Krieger Institute, the Johns Hopkins University School of Medicine, USA3 Kennedy Krieger Institute, Baltimore USAAlthough numerous studies have examined treatments for increasing food consumption among childrenwith pediatric feeding disorders, very few have examined treatment of other mealtime-related difficulties.One such problem is a slow pace of self-feeding, which can lead to caregivers failure to adhere totreatments or be disruptive to others. We examined the effects of a differential reinforcement of high rate(DRH) intervention to increase a 9-year-old boy’s pace of self-feeding. During treatment, the childreceived reinforcement contingent on consuming his meal within 30 min. Results showed an increase inthe pace of self-feeding and a concomitant decrease in meal duration as compared to baseline. Copyright# 2008 John Wiley & Sons, Ltd.INTRODUCTIONMealtime behavior problems (e.g., food refusal, food selectivity, and disruptivebehavior) are relatively common in the pediatric population and are exhibited bychildren with and without developmental disabilities. Research suggests that 25–35%of typically developing children has some form of feeding problem, and theprevalence of feeding disorders is higher among individuals with disabilities and canreach as high as 80% among individuals with severe and profound mental retardation(Linscheid, 1992; Palmer, Thompson, & Linscheid, 1975). Mealtime behaviorproblems are associated with an insufficient intake of nutrients and weight loss, whichcan have a harmful impact on children’s physical, social, and educationaldevelopment (Linscheid, Budd, & Rasnake, 1995).Although there is a growing body of research demonstrating the efficacy ofbehavioral interventions in increasing food acceptance/consumption (Iwata, Riordan,Wohl, & Finney, 1982; Kerwin, 1999), very few studies have examined other*Correspondence to: SungWoo Kahng, Department of Behavioral Psychology, Kennedy Krieger Institute, 707 N.Broadway, Baltimore, MD 21205, USA. E-mail: Kahng@kennedykrieger.orgCopyright # 2008 John Wiley & Sons, Ltd.

18 K. M. Girolami et al.mealtime-related difficulties such as staying seated, using appropriate utensils, andpace of self-feeding. The latter behavior, pace of self-feeding (i.e., the individualaccepts food but eats at an excessively rapid or slow pace), has been the focus of alimited amount of research. Although studies have evaluated methods of decreasingrapid self-feeding (Lennox, Miltenberger, & Donnelly, 1987; Wright & Vollmer,2002), eating too slowly (i.e., dawdling) has very rarely been examined.Eating too slowly during meals may result in lengthy meals, which is oftentimesdifficult and impractical for caregivers. This may in turn, lead some caregivers to relyupon less acceptable methods such as feeding the child. Dawdling during meals mayalso be problematic if the child is school-aged and has a limited amount of time to eat.In this instance, meals may be terminated early or the class schedule may be disruptedif the other students are required to wait.Luiselli (1988) used a prompting procedure to increase the pace of self-feeding in achild with developmental disabilities. The participant was physically prompted totake a bite of food if she had not taken a bite within a certain period of time. Althougheffective in increasing the pace of self-feeding, the prompting procedure may bedifficult to implement given the need for constant monitoring. The purpose of thepresent study was to use a reinforcement-based procedure to increase the pace of selffeeding.Ideally, this intervention would require minimal prompting allowing for easeof implementation.METHODParticipantJude, a 9-year-old boy, was referred to the day treatment program for evaluation andtreatment for food refusal. Jude was diagnosed with failure to thrive, gastroesophagealreflux, attention deficit hyperactivity disorder (ADHD), and gastrostomy tubedependence. He took a constant dose of methylphenidate (MPH) throughout thisevaluation. Jude received approximately 60% of his nutritional needs through hisgastrostomy tube, due to his lack of solid and liquid intake by mouth. Although Judewould eat on occasion, he would not consume enough to sustain his needs, especially ina reasonable amount of time. A typical meal at home was terminated at about 35–45 min. If his parents tried to increase his food consumption, it took up to 1 hr. Despitelengthy meal times, he typically only consumed a few pieces of food.Dependent Variables, Data Collection, and Interobserver AgreementThe target behaviors were (a) number of independent bites consumed (i.e., howmany bites Jude consumed without a verbal prompt), which were converted to a rateCopyright # 2008 John Wiley & Sons, Ltd. Behav. Intervent. 24: 17–22 (2009)DOI: 10.1002/bin

Increasing self-feeding 19measure (bites per min) and (b) duration of the meal (min). The main goal was toincrease bites per min and decrease the amount of time it took him to eat an ageappropriate meal portion.All sessions were conducted in a therapy room (3 m by 3 m). Observers were in theroom collecting data on laptop computers. A second observer independently collecteddata during 50 and 42% of the sessions in baseline and treatment, respectively.Interobserver agreement was calculated by dividing the total number of agreementsby the total number of agreements and disagreements. An agreement was defined aseach 10-s interval in which both observers scored the occurrence or the nonoccurrenceof the behavior. Interobserver agreement was 95% (range, 88–98%) and92% (range, 67–98%) during baseline and treatment, respectively.ProceduresBaselineDuring baseline, Jude was instructed to eat 170 g of solid food and drink 118 ml ofliquid (the liquid was eventually increased to 177 ml) within 30 min (based on aparental interview). A timer set at 30 min was placed on a table nearby and was visibleto Jude. There were no social consequences for consumption during the meal;however, Jude was given a verbal prompt to ‘take a bite’ or ‘take a drink’ if 2 min hadelapsed between bites of food or sips of drink. Therapists interacted with Jude byreciprocating conversation. Meals were terminated at 45 min.TreatmentTreatment consisted of differential reinforcement of high rate (DRH) behavior.This condition was similar to baseline except that if he consumed all of his food anddrink in 30 min or less, he received 10-min access to a video, which was identified ashis most highly preferred stimulus through a preference assessment (Fisher, Piazza,Bowman, Hagopian, Owens, & Slevin, 1992). During treatment, Jude was againinstructed that the goal was to finish his meal in 30 min or less. Additionally, he wasinformed that if he met this goal, he would receive 10-min access to a Scooby Doo 1video. During treatment sessions, Jude was verbally prompted to ‘take a bite’ or ‘takea drink’ every 2 min, as in the baseline condition. Meals were terminated at 45 min.After 30 min elapsed, the timer beeped. If Jude consumed all his food and drink hewas provided access the Scooby Doo 1 video. If Jude did not finish his food and drinkwithin the 30-min time limit, he was told that he did not meet his goal but still had15 min to finish his meal.Copyright # 2008 John Wiley & Sons, Ltd. Behav. Intervent. 24: 17–22 (2009)DOI: 10.1002/bin

20 K. M. Girolami et al.Experimental DesignA multi-element design was used to demonstrate experimental control. In order toenhance discrimination across conditions, different colored tablecloths were used(baseline—yellow and DRH—green). The two conditions were randomly assignedto each meal and counterbalanced across meals (breakfast, lunch, and dinner). Datawere collected over a 3-week period starting when the participant was first admitted tothe hospital.RESULTS AND DISCUSSIONFollowing the initial introduction of treatment, there was minimal differentiation inresponding between the two conditions (baseline and treatment). However, astreatment continued, the DRH intervention resulted in a significant increase in the rateof self-feeding (Figure 1, Top Panel). During baseline, the rate of self-feeding was1.6 per min. During treatment, the self-feeding increased to 2.0 per min. This increase inthe pace of self-feeding led to a decrease in meal duration. During baseline, the averageduration of meals was 35.5 min (Figure 1, Bottom Panel). During treatment, the averageduration of meals decreased to 25.3 min, which amounted to a nearly 30% reduction inthe duration of meals. Furthermore, Jude was completely weaned from the gastrostomytube over the course of the 8-week admission and no longer needed supplementalfeedings, as he was able to gain sufficient weight and maintain his needs from oral feeds.At the time of discharge, he was consistently eating 170 g of solid food and drinking177 ml of liquid in 30 min or less with his primary caregiver.We evaluated a DRH procedure to increase the pace of self-feeding. DRH resultedin an increased pace of self-feeding and a shorter meal duration. This studydemonstrated that a simple differential reinforcement procedure could increase selffeedingwith minimal prompting. This, in turn, may have led to ease ofimplementation for the caregiver, which may ultimately improve treatment integrity.It is interesting to note that Jude took a constant dose of MPH throughout this study.Given that one of the primary adverse side effects of MPH is loss of appetite, this maypartially account for his slow pace of self-feeding. Despite this potential side effect,our DRH intervention was successful in increasing Jude’s pace of self-feeding.In this study, Jude had to wait up to 30 min to receive reinforcement during treatment.For children with more severe disabilities and/or more severe feeding problems,30 min may be too long of a delay to reinforcement. Future studies should examinealternative methods of providing more immediate reinforcement (e.g., tokens).Given that initially there was minimal differentiation between the two conditions(i.e., baseline and treatment); it may be the case that Jude had difficulty discriminatingCopyright # 2008 John Wiley & Sons, Ltd. Behav. Intervent. 24: 17–22 (2009)DOI: 10.1002/bin

Increasing self-feeding 214Baseline(5.1)TreatmentIndependent Bites Per Min3210Increase to 177mls liquidJude0 2 4 6 8 10 12 14 16 18MealsBaselineDRA50BaselineTreatment40Increase to 177mls liquidMeal Duration (Min)30201000 2 4 6 8 10 12 14 16 18MealsFigure 1. Independent bites per minute (Top Panel) and meal duration (Bottom Panel) during baselineand treatment for Jude.Judebetween the two conditions or that there was carryover between the conditions. Inorder to minimize this problem, we used salient discriminative stimuli (differentcolored tablecloths) to enhance discrimination between the two conditions.Eventually, there was clear differentiation in responding between the two conditions,with bite rate higher during treatment. Nevertheless, future studies should examineusing alternative single-case experimental designs such as a reversal design to avoidthis potential problem. This lack of immediate differentiation in responding betweenbaseline and treatment may also bring into question whether or not experimentalcontrol was demonstrated. However, as the treatment evaluation continued, weCopyright # 2008 John Wiley & Sons, Ltd. Behav. Intervent. 24: 17–22 (2009)DOI: 10.1002/bin

22 K. M. Girolami et al.observed a modest level of differentiation across the two treatment conditions in termsof the independent bites per min and the duration of the meals.Follow-up data were not available as the family was from out of state and unable toattend follow-up appointments. However, during phone contacts over a 3-monthperiod after discharge, the primary caregiver reported that Jude was not receiving tubefeedings and meeting his goals the majority of time.Finally, the generality of these findings are limited in the sense that this study onlyincluded one participant. Therefore, future studies should continue to evaluate the useof DRH as a means of increasing the pace of self-feeding. Despite this limitation, thisstudy provides support for the use of differential reinforcement to increaseappropriate mealtime behaviors.ACKNOWLEDGEMENTSThis research is based on a project submitted in partial fulfillment of requirementsfor the MA degree by the first author. We thank David Richman for comments onearlier versions of this paper and Annie Stipicevic for her assistance in this project.REFERENCESFisher, W., Piazza, C. C., Bowman, L. G., Hagopian, L. P., Owens, J. C. & Slevin, I., (1992).A comparison of two approaches for identifying reinforcers with severe and profound disabilities.Journal of Applied Behavior Analysis, 25, 491–498.Iwata, B. A., Riordan, M. M., Wohl, M. K., & Finney, J. W. (1982). Pediatric feeding disorders:Behavioral analysis and treatment. In A. J. Accardo (Ed.), Failure to thrive in infancy and earlychildhood: A multi-disciplinary team approach (pp. 296–329). Baltimore: University Park Press.Kerwin, M. E. (1999). Empirically supported treatments in pediatric psychology: Severe feedingdisorders. Journal of Pediatric Psychology, 24, 193–214.Lennox, D. B., Miltenberger, R. G., & Donnelly, D. R. (1987). Response interruption and DRL for thereduction of rapid eating. Journal of Applied Behavior Analysis, 20, 279–284.Linscheid, T. R. (1992). Eating problems in children In C. E. Walker, & M. C. Roberts (Eds.), Handbookof clinical child psychology. (2nd ed., pp. 451–473). New York: Wiley.Linscheid, T. R., Budd, K. S., & Rasnake, L. K. (1995). Pediatric feeding disorders. In C. R. Roberts(Ed.), Handbook of pediatric psychology (2nd ed., pp. 501–515). New York: Guilford.Luiselli, J. K. (1988). Improvement of feeding skills in multihandicapped students through pacedpromptinginterventions. Journal of the Multihandicapped Person, 1, 17–30.Palmer, S., Thompson, R. J., & Linscheid, T. R. (1975). Applied behavior analysis in the treatment ofchildhood feeding problems. Developmental, Medical, and Child Neurology, 17, 333–339.Wright, C. S., & Vollmer, T. R. (2002). Evaluation of a treatment package to reduce rapid eating. Journalof Applied Behavior Analysis, 35, 89–93.Copyright # 2008 John Wiley & Sons, Ltd. Behav. Intervent. 24: 17–22 (2009)DOI: 10.1002/bin