Functional analysis methodology: Some closing comments

Functional analysis methodologies have emerged as powerful tools in research on the assessment and treatment of severe behavior disorders. Although the defining feature of these approaches is the systematic identification of environmental determinants of behavior, research methodology has varied widely with respect to the arrangements used to demonstrate experimental control as well as the types of variables subject to analysis. This commentary summarizes methodological and conceptual issues that have been raised in current research and offers some suggestions for their resolution.     

THE FUNCTIONS OF SELF-INJURIOUS BEHAVIOR: AN EXPERIMENTAL-EPIDEMIOLOGICAL ANALYSIS

Data are summarized from 152 single-subject analyses of the reinforcing functions of self-injurious behavior (SIB). Individuals with developmental disabilities referred for assessment and/or treatment over an 11-year period were exposed to a series of conditions in which the effects of antecedent and consequent events on SIB were examined systematically by way of multielement, reversal, or combined designs. Data were collected during approximately 4,000 experimental sessions (1,000 hr), with the length of assessment for individuals ranging from 8 to 66 sessions (M = 26.2) conducted over 2 to 16.5 hr (M = 6.5). Differential or uniformly high responding was observed in 145 (95.4%) of the cases. Social-negative reinforcement (escape from task demands or other sources of aversive stimulation) accounted for 58 cases, which was the largest proportion of the sample (38.1%). Social-positive reinforcement (either attention or access to food or materials) accounted for 40 (26.3%) of the cases, automatic (sensory) reinforcement accounted for 39 (25.7%), and multiple controlling variables accounted for 8 (5.3%). Seven sets of data (4.6%) showed either cyclical or inconsistent patterns of responding that were uninterpretable. Overall results indicated that functional analysis methodologies are extremely effective in identifying the environmental determinants of SIB on an individual basis and, subsequently, in guiding the process of treatment selection. Furthermore, an accumulation of assessment data from such analyses across a large number of individuals provides perhaps the most rigorous approach to an epidemiological study of behavioral function.     

PROTECTIVE EQUIPMENT AS TREATMENT FOR STEREOTYPIC HAND MOUTHING: SENSORY EXTINCTION OR PUNISHMENT EFFECTS?

We examined the effects of noncontingent and contingent protective equipment as treatment for self-injurious hand mouthing exhibited by 2 individuals with profound mental retardation. Results of a functional analysis assessment revealed that neither subject's self-injury was maintained by social reinforcement: One subject's self-injury was cyclical in nature; the other's occurred during all assessment conditions but most frequently when left alone. In the noncontingent-equipment condition, oven mitts were placed on the individual's hands at the beginning of a session and remained on throughout. In the contingent-equipment condition, the mitts were briefly placed on the individual's hands following occurrences of hand mouthing. For 1 subject, noncontingent mitts produced a large decrease in the rate of hand mouthing and contingent mitts produced similar results following a return to baseline. Hand mouthing was also reduced in the 2nd subject, but this individual was exposed only to the contingent-equipment condition (i.e., there was no prior history with the noncontingent-equipment condition). These results suggest either a punishment or a time-out interpretation rather than an extinction interpretation to account for the behavior-reducing effects of contingent protective equipment on self-injury.     

A descriptive analysis of social consequences following problem behavior.

The social consequences delivered for problem behavior during functional analyses are presumed to represent common sources of reinforcement; Final acceptance however, the extent to which these consequences actually follow problem behavior in natural settings remains unclear. The purpose of this study was to determine whether access to attention, escape, or tangible items is frequently observed as a consequence of problem behavior under naturalistic conditions. Twenty‐seven adults who lived in a state residential facility and who exhibited self‐injurious behavior, aggression, or disruption participated. Observers recorded the occurrence of problem behavior by participants as well as a variety of consequences delivered by caregivers. Results indicated that attention was the most common consequence for problem behavior and that aggression was more likely to produce social consequences than were other forms of problem behavior.     

Longitudinal analysis of leisure-item preferences.

Twenty‐two individuals with developmental disabilities participated in two leisure‐item preference assessments, spaced approximately 16 months apart. Results showed (a) an overall increase in item contact across assessments for 13 participants and (b) at least some overlap across assessments in the five most highly ranked items for every participant. These results highlight individual differences in the stability of preference over time and suggest the need for research to identify the determinants of temporal shifts in preference.     

Functional analysis and treatment of problem behavior evoked by noise.

We conducted a four‐part investigation to develop methods for assessing and treating problem behavior evoked by noise. In Phase 1, 7 participants with developmental disabilities who were described as being hypersensitive to specific noises were exposed to a series of noises under controlled conditions. Results for 2 of the participants verified that noise was apparently an aversive event. In Phase 2, results of functional analyses indicated that these 2 participants' problem behaviors were maintained by escape from noise. In Phase 3, preference assessments were conducted to identify reinforcers that might be used during treatment. Finally, in Phase 4, the 2 participants' problem behaviors were successfully treated with extinction, stimulus fading, and a differential‐reinforcement‐of‐other‐behavior (DRO) contingency (only 1 participant required DRO). Treatment effects for both participants generalized to their home environments and were maintained during a follow‐up assessment. Procedures and results were discussed in terms of their relevance to the systematic assessment of noise as an establishing operation (EO) and, more generally, to the identification of idiosyncratic EO influences on behavior.     

Do Mothers and Fathers Assess their Children's Behavioral Problems in the Same Way as do their Children? An IRT Investigation on the Strengths and Difficulties Questionnaire

This study investigated the equivalence of different types of informants, such as children (or early adolescents) and parents, in evaluating child externalizing and internalizing problems. We applied a polytomous item response theory (IRT) model for the Strengths and Difficulties Questionnaire (SDQ). We obtained responses to three subscales—Conduct Problems, Hyperactivity/Inattention, and Emotional Symptoms—from 541 elementary school students aged 10–12 years, fathers for 233 students, mothers for 275 students, and the homeroom teachers for 524 students. Expected values on the individual item calculated by the discrimination and threshold parameters were compared among students, fathers, and mothers as an investigation of differential item functioning (DIF) or differential informant functioning. Assessing either externalizing or internalizing problems were mostly equivalent between fathers and mothers, and most items for externalizing problems functioned equally between students and parents, whereas items for internalizing problems showed DIF between them. IRT also yielded that the intervals of response categories varied across items, particularly for the conduct problems items “fight” and “steal,” and positively worded items showed an extremely low threshold.     

False-positive tangible outcomes of functional analyses

Functional analysis (FA) methodology is the most precise method for identifying variables that maintain problem behavior. Occasionally, however, results of an FA may be influenced by idiosyncratic sensitivity to aspects of the assessment conditions. For example, data from several studies suggest that inclusion of a tangible condition during an FA may be prone to a false-positive outcome, although the extent to which tangible reinforcement routinely produces such outcomes is unknown. We examined susceptibility to tangible reinforcement by determining whether a new response was acquired more readily when exposed to a tangible contingency relative to others commonly used in an FA (Study 1), and whether problem behavior known not to have a social function nevertheless emerged when exposed to tangible reinforcement (Study 2). Results indicated that inclusion of items in the tangible condition should be done with care and that selection should be based on those items typically found in the individual's environment.