TEST-SPECIFIC CONTROL CONDITIONS FOR FUNCTIONAL ANALYSES TARA A. FAHMIE BRIAN A. IWATA ANGIE C. QUERIM JILL M. HARPER

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1 JOURNAL OF APPLIED BEHAVIOR ANALYSIS 213, 46, 61 7 NUMBER 1(SPRING 213) TEST-SPECIFIC CONTROL CONDITIONS FOR FUNCTIONAL ANALYSES TARA A. FAHMIE CALIFORNIA STATE UNIVERSITY, NORTHRIDGE BRIAN A. IWATA UNIVERSITY OF FLORIDA ANGIE C. QUERIM UNIVERSITY OF NEBRASKA AND JILL M. HARPER MELMARK NEW ENGLAND Most functional analyses of problem behavior include a common condition (play or noncontingent reinforcement) as a control for both positive and negative reinforcement. However, test-specific conditions that control for each potential source of reinforcement may be beneficial occasionally. We compared responding during alone, ignore, play, and differential reinforcement of other behavior (DRO) control conditions for individuals whose problem behavior was maintained by positive or negative reinforcement. Results showed that all of the conditions were effective controls for problem behavior maintained by positive reinforcement; however, the DRO condition was consistently ineffective as a control for problem behavior maintained by negative reinforcement. Implications for the design of functional analyses and future research are discussed. Key words: control conditions, functional analysis, pairwise design A functional analysis (FA) of problem behavior involves observation of behavior under both test and control conditions (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994). Test conditions include the presentation of contingencies (establishing operations and consequences) suspected to maintain behavior, whereas the control condition eliminates the influence of contingencies included in the test conditions. Conclusions about the function of problem behavior are made when responding occurs in at least one test condition but is minimal or absent in the control condition. Correspondence concerning this article should be addressed to Brian A. Iwata, Psychology Department, Room 114 Psychology Building, University of Florida, Gainesville, Florida ( iwata@ufl.edu). doi: 1.12/jaba.9 Iwata et al. (1982/1994) used a common condition play as a control for both positive (delivery of attention) and negative (escape from demands) reinforcement in their FA, which simplified assessment by minimizing the number of concurrent comparisons. The play condition involved free access to attention and highly preferred leisure items combined with the absence of demands. Thus, the condition served as a noncontingent reinforcement (NCR) control for behavior maintained by either positive or negative reinforcement. The play condition is the most commonly used control in experimental studies on assessment because it consistently yields low rates of problem behavior. For example, Fischer, Iwata, and Worsdell (1997) compared responding during the attention (contingent reinforcement), play (noncontingent reinforcement), and alone 61

2 62 TARA A. FAHMIE et al. (extinction) conditions for 36 individuals whose self-injurious behavior (SIB) was maintained by attention and found that responding was lowest in the play condition for the majority (31) of subjects. Nevertheless, the play condition may contain features that occasionally produce higher rates of problem behavior. Kahng and Iwata (1998) compared responding during the demand, play, and alone conditions for 66 subjects with SIB maintained by escape and found that responding was higher in the play condition than in the alone condition for 45 subjects. Because the play condition shared stimulus features with the demand condition (the presence of a therapist), the play condition may have acquired discriminative properties associated with escape responding for some subjects. In addition, the play condition contained frequent interactions between therapist and subject, which may have occasioned behavior maintained by avoidance of social interaction in general (see also Harper, Iwata, & Camp, 213). Although social avoidance was not confirmed by Kahng and Iwata, they noted that the play condition evoked a relatively high level of SIB in five cases. Taken together, results of these two studies suggest that the play and alone conditions may be superior controls for maintenance by social positive and social negative reinforcement, respectively, in an FA. Although the play and alone conditions have been compared, the utility of other conditions has not been examined in the context of FA research. For example, the ignore condition, in which a therapist is present but does not interact with the subject at all during the session, is the only possible substitute for the alone condition when practical constraints, such as the lack of an observation room or the inability to leave a young child unattended, do not permit a true alone condition or when the target problem behavior consists of aggression. The presence of a person in the ignore condition, however, may serve as a discriminative stimulus for behavior maintained by either attention or escape. As an alternative, perhaps a differential reinforcement of other behavior (DRO) condition, in which social interaction of a nonwork nature is delivered contingent on the absence of problem behavior, would be a more effective control than the ignore condition. Thompson, Iwata, Hanley, Dozier, and Samaha (23) conducted a comparison of multiple control conditions in the context of response acquisition. Target responses were reinforced with edible items on a continuous schedule during the test condition. The authors compared responding in this condition to responding in extinction (EXT; no edible items), DRO (edible items following a period of no responding), and NCR (fixed-time [FT] delivery of edible items) control conditions. Responding was assessed along several dimensions, including rate and amount of response decrement, rate of response recovery when reinforcement was reintroduced (as in a reversal), and side effects (e.g., EXT bursts). Results showed that EXT was the most effective and efficient control condition. It is unclear, however, whether the same would apply to conditions of an FA. Although newly established behavior might extinguish quickly, problem behavior with a longer history of reinforcement might be maintained for longer periods of time during EXT. An evaluation of control conditions in the context of the functional analysis of problem behavior, therefore, requires further comparative research. The purpose this study was to determine the most effective controls for positive and negative reinforcement in the assessment of problem behavior. METHOD Subjects and Setting Eight individuals with intellectual disabilities participated. All subjects were students at a special education school and had been referred for assessment of their problem behavior. Brad was an 11-year-old boy who had been diagnosed with Dandy Walker syndrome and attention deficit

3 FUNCTIONAL ANALYSIS CONTROL CONDITIONS 63 hyperactivity disorder, Paul was a 22-year-old man who had been diagnosed with an intellectual disability (ID), Elijah was a 7-year-old boy who had been diagnosed with autism, Tim was a 4- year-old boy who had been diagnosed with autism, Kelly was an 11-year-old girl who had been diagnosed with an ID, Kim was a 12-yearold girl who had been diagnosed with an ID, Cecille was a 12-year-old girl who had been diagnosed as other health impaired, and Ellyse was a 16-year-old girl who had been diagnosed with an ID. All subjects also had been diagnosed as language impaired. Sessions were conducted in a therapy room near the individuals classrooms. Sessions lasted 1 min and were conducted one to four times per day, 3 to 5 days per week. The same therapist conducted all conditions of each subject s FA but wore shirts of different colors, each color uniquely associated with one condition, to enhance discrimination between conditions. Response Measurement and Reliability The dependent measure for FAs was the rate or percentage of 1-s intervals of problem behavior, which was defined on an individual basis. Brad engaged in property destruction (tearing paper from the walls, throwing or banging objects, and overturning furniture). Prior to each of Brad s sessions, the room was baited for property destruction by taping paper to the walls of the room and by rearranging any furniture that Brad had previously overturned. Elijah engaged in dangerous acts (climbing on furniture and touching electrical outlets). All electrical outlets in the room had covers to ensure his safety. One piece of furniture, a child-sized chair, was placed in the center of the room for each of his sessions, and climbing was defined as any part of the bottom of the foot in contact with any part of the seat of the chair. This arrangement and definition for climbing prevented Elijah from engaging in behavior that could result in injury. Tim and Kelly engaged in SIB (hand biting). Paul, Kim, Cecille, and Ellyse engaged in aggression (grabbing, pinching, hitting, or scratching the therapist). Trained observers used handheld computers to record data on target behaviors. Reliability was assessed by having a second observer simultaneously but independently collect data during a mean of 46% of sessions (range, 3% to 67%) across subjects. Sessions were divided into 1-s intervals, and observers records were compared on an interval-by-interval basis. Agreement for frequency measures was calculated by dividing the smaller number of responses by the larger number of responses in each interval and averaging these values across the session. Agreement for percentage interval measures was calculated by dividing the number of intervals in which both observers agreed on the occurrence or nonoccurrence of the behavior by the total number of intervals. Mean agreement on target responses across subjects was 95% (range of session means, 7% to 1%). Procedure Initial FA. A multielement FA, similar to that described by Iwata et al. (1982/1994), was conducted to identify the function of each subject s target behavior. Assessment conditions were alternated across sessions in a fixed sequence: ignore, attention, play, and demand. This series was repeated until a group consensus was reached on the function of problem behavior. Only subjects whose problem behavior showed a social-positive or social-negative function were included in this study. In the ignore condition, a therapist was present, but no attention or materials were delivered to the subject. This condition was included to test for maintenance of problem behavior by automatic reinforcement. In the attention condition, the therapist engaged in a solitary activity (e.g., reading a magazine) and delivered 5 to 1 s of attention (brief statements of concern) following each instance of problem behavior. The subject had free access to moderately preferred leisure items identified

4 64 TARA A. FAHMIE et al. using a paired-stimulus preference assessment (Fisher et al., 1992). The attention condition was included to test for maintenance of problem behavior by social-positive reinforcement. In the play condition, the therapist interacted with the subject according to an FT 3-s schedule and responded to the subjects appropriate social initiations. The subject had free access to highly preferred leisure items (identified in the pairedstimulus preference assessment). All instances of problem behavior were ignored during the play condition, which served as a control. In the demand condition, the therapist used a three-step prompting hierarchy (verbal, model, and physical prompts) to present tasks that were reported to be difficult for the subject. The subject received a 3-s break from tasks contingent on each instance of problem behavior. This condition was included to test for maintenance of problem behavior by social-negative reinforcement. Comparison of control conditions. The test condition associated with the highest level of problem behavior during the functional analysis (attention or demand) was alternated with several control conditions (alone, ignore, play, and DRO) during the control comparison. No therapist was present during the alone condition; observation was done from behind a one-way mirror. A therapist stood with his or her back turned toward the subject during the ignore condition and did not interact with the subject. A therapist presented attention (positive statements) on an FT 15-s schedule and responded to the subject s appropriate social initiations during the play condition. The schedule of attention was increased relative to the play condition of the initial FA to increase the likelihood of response suppression. The DRO condition involved the delivery of the relevant reinforcer (attention or escape from task demands) following a DRO interval with the absence of problem behavior. The DRO interval requirement was equal to the mean interresponse time (IRT) from the immediately preceding test session. For problem behaviors scored using a frequency measure, the DRO interval was calculated by dividing the number of seconds in a session (6) by the number of responses that occurred in the immediately preceding test session. For target behaviors scored using a percentage of session interval measure, the DRO interval was equal to the mean number seconds between session intervals with a target response and was calculated using the following equation: 1 percentage of session intervals with target behavior (converted to a decimal) 1 (Repp, Felce, & Barton, 1991). For subjects with problem behavior maintained by attention, the DRO condition involved the delivery of attention (positive statements) following each DRO interval with no problem behavior. For subjects with problem behavior maintained by escape, the DRO condition involved the continuous delivery of tasks (in the same manner described for the demand condition) and the removal of tasks for 3 s following each DRO interval with no problem behavior. Moderately preferred leisure items (the same as those used in the attention condition of the initial FA) were freely available in all control conditions except in the DRO condition for individuals with problem behavior maintained by escape because this condition involved delivery of task demands. Table 1 summarizes the presumed functional differences between each test condition and its relevant controls. One test condition was conducted before each control condition in a multielement design. The four control conditions were randomized across eight-session blocks (four test, four control). The control comparison for Paul, Kim, Cecille, and Ellyse did not include the alone condition because these subjects engaged in aggression. Sessions were conducted until a stable, differentiated pattern of responding emerged, or until undifferentiated data were either stable or trending in a predictable manner. RESULTS Figure 1 shows results for subjects whose problem behavior was maintained by attention. Brad s property destruction, Paul s aggression,

5 FUNCTIONAL ANALYSIS CONTROL CONDITIONS 65 Table 1 Functional Differences Between Test and Control Conditions Condition EO S D Consequence Reinforcement contingency Positive reinforcement (Srþ) test Attention þ þ þ Srþ for problem behavior Positive reinforcement (Srþ) controls Alone þ Extinction Ignore þ þ Extinction DRO þ þ Srþ for absence of problem behavior Play þ Noncontingent and differential Srþ Negative reinforcement (Sr ) test Demand þ þ þ Sr for problem behavior Negative reinforcement (Sr ) controls Alone Noncontingent Sr Ignore þ Noncontingent Sr DRO þ þ Sr for absence of problem behavior Play þ Noncontingent Sr Note. Plus signs indicate presence of an establishing operation (EO), discriminative stimulus (S D ), or reinforcing consequence; minus signs indicate their absence. and Elijah s dangerous acts occurred at high levels in the attention condition relative to other conditions during their initial FAs as well as during their comparison of control conditions. That is, problem behavior for all subjects was lower during all control conditions than it was during the attention condition, although to varying degrees. Brad s problem behavior remained at near-zero rates during the play and DRO control conditions. His problem behavior occurred at low-to-moderate rates in the alone and ignore conditions, although it sometimes overlapped with rates in the attention condition. Paul never engaged in aggression in the ignore condition and exhibited very low levels of aggression in the DRO and play conditions. Elijah engaged in near-zero levels of problem behavior in the alone condition and in low-tomoderate levels of problem behavior in the DRO, ignore, and play conditions. Figure 2 shows data for subjects whose SIB (Tim and Kelly) or aggression (Kim, Cecille, and Ellyse) was maintained by escape. All subjects engaged in higher rates of problem behavior in the demand condition of their initial FAs and continued to engage in problem behavior in the demand condition during their comparisons of control conditions. Different patterns of responding were observed, however, during their control comparisons. The only control conditions that yielded consistently low rates of problem behavior were the ignore (all subjects) and the alone (Tim and Kelly) conditions. Four of the five subjects engaged in lower rates of problem behavior during the play condition; however, Ellyse engaged in similar rates of problem behavior during her play and demand conditions. Finally, all subjects engaged in rates of problem behavior in the DRO condition that were similar to (Tim, Kelly, and Cecille) or noticeably higher than (Kim and Ellyse) those observed in the demand condition. Table 2 summarizes results of the control comparisons for all subjects. DISCUSSION Results of this study showed that the common control (play) condition used in most FAs compared favorably with other test-specific controls for problem behavior maintained by social-positive and social-negative reinforcement. The play condition was associated with low rates of problem behavior (compared to the relevant

6 66 TARA A. FAHMIE et al. PROPERTY DESTRUCTION (RPM) Functional Analysis Control Comparison Attn Ignore Alone DRO Play Dem Brad AGGRESSION (% INT) Paul DANGEROUS ACTS (RPM) Elijah SESSIONS Figure 1. Results of the initial FA and control comparison for individuals whose problem behavior was maintained by attention. Dem ¼ demand condition, Attn ¼ attention condition. test condition) for seven of eight subjects. The exception was Ellyse, whose escape-maintained problem behavior occurred at similar rates in the demand and play conditions. Given that her problem behavior was elevated in every condition that contained social interaction initiated by the therapist (demand and play conditions of her initial FA; demand, play, and DRO conditions of her control comparison), it is likely that her behavior represented a more general form of social avoidance, although we did not conduct a direct test of this possibility.

7 FUNCTIONAL ANALYSIS CONTROL CONDITIONS 67 AGGRESSION (RPM) HAND BITING (RPM) AGGRESSION (RPM) 3 2 Ignore 1 Functional Analysis Control Comparison Functional Analysis Control Comparison DRO Dem Attn Play Alone Tim Kim Ellyse SESSIONS Kelly Cecille SESSIONS Figure 2. Results of the initial FA and control comparison for individuals whose problem behavior was maintained by escape. Dem ¼ demand condition, Attn ¼ attention condition. One interesting finding of the current study was the consistency with which the DRO condition produced high levels of escapemaintained behavior. This outcome likely was obtained because the DRO condition was the only control condition that presented the EO for escape (i.e., demands). Although DRO has been shown to be an effective treatment for escapemaintained behavior (Buckley & Newchok, 26; Devlin, Healy, Leader, & Reed, 28; Kodak, Miltenberger, & Romaniuk, 23; Vollmer, Marcus, & Ringdahl, 1995), exposure to DRO contingencies during treatment typically is extended across a number of sessions. By contrast, intermittent exposure to the DRO contingency in a multielement FA may fail to suppress responding because single DRO sessions are interspersed among other demand sessions in which problem behavior is reinforced. As a result, extinction of escape-maintained behavior may not occur during the DRO control. A similar finding was not observed with the DRO control for attention-maintained behavior, perhaps because brief periods during which attention is unavailable in the DRO for attention-maintained behavior serve as a weaker EO for problem behavior than brief periods during which demands are present in the DRO for escape-maintained behavior. The manner in which the DRO interval was calculated also may have contributed to the

8 68 TARA A. FAHMIE et al. Table 2 Mean Level of Problem Behavior for Each Condition of the Control Comparison Subject Attention Escape Alone Ignore DRO Play Brad Paul a Elijah Tim Kim Ellyse Kelly Cecille Note. Condition means for problem behavior in the test condition and in the control condition associated with the lowest level of problem behavior are shown in bold type. a Values are expressed as percentage of observation intervals. failure of the DRO contingency to suppress escape-maintained problem behavior. We based the DRO interval on the mean IRT from the preceding demand session because this calculation was relatively simple, quick, and conventional (Vollmer & Iwata, 1992). However, the IRT measure did not take into account reinforcer access time during 3-s breaks contingent on problem behavior in the demand condition. Thus, if a subject engaged in problem behavior 3 s after the onset of the session and 3 s after each subsequent removal of the reinforcer (termination of the break), that subject s uncorrected IRT was 33 s rather than the 3 s that elapsed after each new presentation of the EO. Perhaps not surprisingly, the two subjects (Ellyse and Kim) whose responding was most efficient (approximately two responses per minute) in the demand condition had the highest rates of problem behavior during the DRO condition. Results of previous research suggest that a rich DRO schedule might facilitate suppression of escapemaintained behavior more effectively than a lean schedule. For example, Kodak et al. (23) implemented DRO for escape-maintained behavior by first conducting one session in which escape was continuously available. Subsequent sessions involved small increases (1-s increments, initially) in the DRO interval only when problem behavior was below a predetermined criterion. This progression resulted in relatively quick and enduring suppression of problem behavior. By contrast, applications of DRO for escape-maintained behavior that failed to immediately suppress behavior have involved DRO intervals set equal to (Vollmer et al., 1995) or greater than (Roberts, Mace, & Daggett, 1995) the mean IRT. Thus, future research might examine the utility of the DRO control condition during FAs based on different IRT calculations. Quick suppression of behavior is of critical importance in the design of control conditions for FAs, and for this reason, the current study focused on the degree of response suppression in the control conditions. That is, conditions that resulted in the lowest level of responding were considered to be more effective. Beyond such practical considerations, however, methodological rigor is achieved when a control condition isolates (i.e., removes) the relevant reinforcement contingency while all other stimulus features of the condition are held constant (see Thompson & Iwata, 25, for a more extensive discussion of this point). The control conditions of the current study varied across several stimulus features (see Table 1); thus, some conditions were more experimentally rigorous than others. Although we attempted to yoke some stimulus features (e.g., access to moderately preferred leisure items) across conditions, other features (e.g., therapist s shirt color) intentionally differed for practical reasons. An increase in experimental rigor could

9 FUNCTIONAL ANALYSIS CONTROL CONDITIONS 69 have been achieved by yoking additional features of the conditions (e.g., timing and duration of reinforcer deliveries); however, these changes likely would have required additional effort or manipulations whose effects on FA outcomes have not been clearly established. Results of the current study demonstrate a case in which a control condition that shared many (DRO) versus fewer (alone) stimulus features with a test condition (demand) produced less satisfactory results. Future research might consider the extent to which the methodological rigor of control conditions influences FA outcomes. Despite the general effectiveness of the play condition as a control across social functions, the ignore or alone conditions may be preferred controls for social-negative reinforcement because they were effective for all subjects whose behavior was maintained by escape. When the function of problem behavior is unknown, it is likely that both conditions play and alone or ignore would be included in an FA, the former as the common control and the latter as a test condition for behavior maintained by automatic reinforcement. Thus, the alone or ignore condition in a typical FA might serve dual purposes. The more important implication of our results pertains to situations in which single test control comparisons are conducted. The first involves the pairwise FA (Iwata, Duncan, Zarcone, Lerman, & Shore, 1994), in which single (test vs. control) multielement comparisons are conducted in a series to minimize carryover effects. Although Iwata et al. used the same control condition (play) across multielement series, it is feasible to incorporate test-specific controls, such as attention versus play and demand versus alone or ignore. A second situation may arise when preliminary data strongly suggest a particular function for problem behavior, which is verified by way of a singlefunction test (Iwata & Dozier, 28). Finally, when problem behavior is found to be occasioned or maintained by unusual events that require subsequent refined analyses, the present data suggest that the preferred control would consist of noncontingent access to the presumed reinforcer delivered in the test condition, as illustrated in several previous studies (e.g., Bowman, Fisher, Thompson, & Piazza, 1997; Fisher, Kuhn, & Thompson, 1998). Although data from the current study showed only a slight benefit to the use of unique control conditions, it is important to note that one requirement for participation was a clear outcome in an initial FA. Perhaps this requirement biased results in favor of the play condition, which was necessarily an effective control during the initial FA. Thus, different results might be obtained when responding under typical FA conditions produces ambiguous outcomes. REFERENCES Bowman, L. G., Fisher, W. W., Thompson, R. H., & Piazza, C. C. (1997). On the relation of mands and the function of destructive behavior. Journal of Applied Behavior Analysis, 3, doi: 1.191/jaba Buckley, S. D., & Newchok, D. K. (26). Analysis and treatment of problem behavior evoked by music. Journal of Applied Behavior Analysis, 39, doi: 1.191/jaba Devlin, S., Healy, O., Leader, G., & Reed, P. (28). The analysis and treatment of problem behavior evoked by auditory stimulation. Research in Autism Spectrum Disorders, 2, doi: 1.116/j.rasd Fischer, S. M., Iwata, B. A., & Worsdell, A. S. (1997). Attention as an establishing operation and as reinforcement during functional analyses. Journal of Applied Behavior Analysis, 3, doi: 1.191/ jaba Fisher, W. W., Kuhn, D. E., & Thompson, R. H. (1998). Establishing discriminative control of responding using functional and alternative reinforcers during functional communication training. Journal of Applied Behavior Analysis, 31, doi: 1.191/jaba Fisher, W., Piazza, C. C., Bowman, L. G., Hagopian, L. P., Owens, J. C., & Slevin, I. (1992). A comparison of two approaches for identifying reinforcers for persons with severe and profound disabilities. Journal of Applied Behavior Analysis, 25, doi: 1.191/ jaba Harper, J. M., Iwata, B. A., & Camp, E. M. (213). Assessment and treatment of social avoidance. Journal of Applied Behavior Analysis, 46, Iwata, B. A., Dorsey, M. F., Slifer, K. J., Bauman, K. E., & Richman, G. S. (1994). Toward a functional analysis of

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