The effectiveness of a hierarchical shaping procedure for eating disorders, targeting food avoidance

Abstract

There is an increase in the prevalence of eating disorders (EDs) among the adult population, with individuals experiencing severe mental and physical impairments that disturb multiple areas of functioning. Despite the disorders’ severity, behavior-analytic research, targeting this population, is limited to nonexistent. Hierarchical shaping procedures are suggested to increase food acceptability and consumption for typical or non-typical developing children. Therefore, this study aimed to assess the effectiveness of a 12-step hierarchical shaping procedure, targeting food avoidance, for individuals with EDs. Two 19-year-old female participants, diagnosed with Avoidant/Restrictive Food Intake Disorder (ARFID) of the sensory sensitivity subtype, were recruited from an inpatient or outpatient hospital program. A changing criterion design was implemented, introducing each of the 12 shaping approximations, targeting four food items. Reported anxiety rates and food refusal behaviors were measured but not directly targeted, to identify any possible changes resulting from the intervention. Both participants successfully met all criteria once they were introduced, leading to the consumption of the four targeted items. Anxiety levels and food refusal behaviors remained relatively stable throughout the intervention and showed a decrease as the intervention was concluding. Generalization in two additional environments and maintenance of treatment outcomes after a two-week follow-up were established for both participants, with food refusal behaviors being absent and anxiety levels remaining low. Overall, the findings indicate the interventions' effectiveness in increasing the consumption of anxiety-provoking food items for individuals with ARFID, adding to the existing literature on shaping procedures and ED interventions. Keywords: shaping, eating disorder, avoidant/restrictive food intake disorder, ARFID, food avoidance