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. Author manuscript; available in PMC: 2021 Jun 22.
Published in final edited form as: Educ Treat Children. 2017 Feb;40(1):43–56. doi: 10.1353/etc.2017.0003

The Long-Term Effects of Functional Communication Training Conducted in Young Children’s Home Settings

David P Wacker 1, Kelly M Schieltz 1, Wendy K Berg 1, Jay W Harding 1, Yaniz C Padilla Dalmau 1, John F Lee 1
PMCID: PMC8218995  NIHMSID: NIHMS1604883  PMID: 34163099

Abstract

This article describes the results of a series of studies that involved functional communication training (FCT) conducted in children’s homes by their parents. The 103 children who participated were six years old or younger, had developmental delays, and engaged in destructive behaviors such as self-injury. The core procedures used in each study were functional analyses (FA) and FCT conducted by parents with coaching by the investigators. The overall results of the projects showed that the FA plus FCT intervention package produced substantial reductions in destructive behavior (M = 90%), which were often maintained following treatment. In terms of behavioral momentum theory, these results suggest that analyses of behavioral persistence provide an explicit technology of maintenance.

Keywords: functional communication training, maintenance, behavioral persistence

Our research team initiated a series of longitudinal studies in 1992 to evaluate the long-term effects of functional communication training (FCT; Wacker & Berg, 1992; Wacker, Berg, & Harding, 1996; Wacker, Berg, & Harding, 2000; Wacker, Berg, & Harding, 2004). In each of these projects, FCT was conducted in the homes of young children who had developmental delays and engaged in severe problem behavior such as self-injury. Parents conducted all assessment and treatment procedures with one hour of coaching per week by our project staff. Although the specific purposes differed across projects, the effects of FCT were always studied via direct observation, often for several months following treatment. In this article, we briefly describe the core procedures used across the projects and summarize the data obtained over an 18-year period. We emphasize the long-term effects achieved and propose a new model for defining and evaluating maintenance.

Core Procedures Used Across Projects

A summary of the specific procedures used in the projects is provided in Harding, Wacker, Berg, Lee, and Dolezal (2009). Briefly, all projects included two phases, with Phase 1 being a functional analysis of behavior (FA; Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) and Phase 2 being functional communication training (FCT; Carr & Durand, 1985). Both the FA and FCT phases were conducted by parents in their homes. Project staff videotaped the parents conducting the procedures for subsequent data collection using six-second partial-interval recording procedures, and provided real-time directions, prompts, and feedback while the parents conducted each five-minute session. We told parents that the results of the FA would give us information regarding why the problem behavior was occurring at home (i.e., to escape demands, to gain attention, or to gain access to preferred items). Throughout these projects, fewer than five parents objected to completing an FA and, in fact, most expressed strong interest in completing this assessment. In most of the projects, an escape function needed to occur during the FA for the family’s continued participation in the project. When a function was identified, the child was taught to appropriately request the outcome identified in the FA. For example, in demand situations, the appropriate mand (i.e., request) was often “play” to request brief enriched breaks from work tasks. In this situation, the child needed to complete one task or one step of a task before manding for a break to play. For most of the children, manding consisted of touching a word card and/or a microswitch with the word play written on it. Thus, compliance produced the card/switch and touching the card/switch produced a 30-second to one-minute break from the demand to play. Completing the task and manding were prompted via a three-step prompt sequence (vocal, model, physical guidance), and as the child began to be successful, the amount of work required was increased across sessions (demand fading). If problem behavior occurred during work, it was ignored (escape extinction). If problem behavior occurred during the break, the child was immediately returned to the work task (response cost).

The core procedures were used with the majority of the children but were often augmented with other procedures depending on the purposes of the project and the specific responses of the child. For examples of these augmentative procedures, see Berg, Wacker, Harding, Ganzer, and Barretto (2007), who evaluated the stimulus generalization produced by FCT, and Harding, Wacker, Berg, Winborn-Kemmerer, and Lee (2009), who evaluated choice responding during FCT. More recently, these same procedures have been conducted via telehealth (Lindgren et al., 2016).

Summary of the Results

During the 18 years of the projects, 103 children and their parents participated. The demographic and diagnostic features of this group are provided in Tables 1 and 2, respectively.

Table 1.

Demographic Characteristics of Participants

Gender Age (months) Race/Ethnicity
Male = 80 Mean = 45 White = 92
Female = 23 Range = 14–83 African American = 7
Latino/Hispanic = 9
Native American = 2
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Table 2.

Diagnostic Status of Participants

Estimated Intellectual Functioning Autism Spectrum Disorder Other Genetic Syndrome Visual or Hearing Disability
Borderline/mild intellectual disability = 73 24 20 23
Moderate to profound intellectual disability = 30
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One focus of each project was early intervention, and this is shown by the participants’ mean age of 45 months. Almost 80% of the participants were male, and 70% were classified as functioning in the borderline to mild range of intellectual disability based on information in their medical or educational records. Approximately 25% of the participants were diagnosed with an autism spectrum disorder (see Lindgren et al., 2016 for a summary of this subgroup of participants).

An enrollment criterion for every project was that the child engaged in destructive behaviors such as self-injury, aggression, or property destruction. Most of the participants engaged in at least two of these responses, with 75 displaying aggression, 66 displaying self-injury, and 57 displaying property destruction. The identified function of these problem behaviors is provided in Table 3.

Table 3.

Identified Function of Destructive Behavior

Function Number and % of Participants
Positive reinforcement only 17 (17.7)
Negative reinforcement only 16 (16.6)
Positive plus negative reinforcement 49 (51)
Undifferentiated 8 (8.3)
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Each FA was conducted in the participants’ homes by their parents. The analyses were completed within a multielement design, with each of four conditions (free play, attention, tangible, and escape) conducted at least three times during two one-hour periods one week apart. The total number of FAs shown in Table 3 is 90, because six children did not show destructive behavior during the FA and the FA procedures were not completed for the remaining children (most often because the family moved out of the project area). The results of the completed FAs show that the vast majority of the children displayed destructive behavior maintained by social functions and that the majority of the children displayed destructive behavior that was maintained by both positive and negative reinforcement.

The effects of FCT on destructive behavior during each project are presented in Table 4. As mentioned previously, FCT sessions were videotaped and later scored by research assistants. Data were coded using a six-second partial-interval recording system, and the results in Table 4 display the percent reductions of the participants’ destructive behavior from baseline to the end of treatment. The reductions were calculated by dividing the average percent occurrence of destructive behavior during baseline sessions (extinction or FA) by the average percent occurrence during the final three treatment sessions. As shown in Table 4, remarkably consistent results occurred during each project. The average decrease across all projects was 90%, with the range being 86% to 96%. Only one participant failed to show improvement.

Table 4.

Percent Reduction of Destructive Behavior across Each Project

NIH 1 (1992–1996) NIH 2 (1996–2000) NIH 3 (2000–2004) NIH 4 (2004–2010) Total
Number who completed treatment 24 23 19 18 84
Mean percent reduction 86% 86% 95% 96% 90%
Range 45–100% 1–100% 38–100% 60–100%
Mean time in treatment (months) 10 5 6 10
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Average length of time in treatment is shown in the bottom row of Table 4. Variability in length of treatment across the projects was mostly a function of the goals of the projects, with the first and fourth projects focusing on long-term effects. The range for length of time in treatment was five months to ten months. This length of time in treatment, when considered with the mean reduction in destructive behavior, strongly suggests that FCT produced reliable long-term effects (see Wacker et al., 2005, and Wacker et al., 1998, for further analyses of these data sets). When considered with other descriptions of the long-term effects achieved via FCT (Berg et al., 2007; Derby et al., 1997; Durand & Carr, 1991; Wacker et al., 2011), it seems reasonable to conclude that FCT produces good maintenance because durable changes in behavior occur over the course of treatment. Of note, is that very similar effects of FCT treatment also occur when all procedures are conducted via telehealth (Wacker et al., 2013).

Further Analysis of Maintenance

As discussed by Nevin and Wacker (2013), many applied studies have defined maintenance as steady-state responding under treatment conditions (e.g., Stokes & Baer, 1977). Maintenance is considered to have occurred when problem behaviors remain steady and at low levels and desired behaviors remain steady and at high levels for a period of time at the end of treatment. In most cases, maintenance is evaluated under either the prevailing conditions of treatment or just immediately following treatment. Multiple baseline or reversal designs are used to show that changes in behavior are a function of treatment, and that steady state responding continues to occur under the conditions of treatment. When steady state responding occurs under treatment conditions, but not under baseline conditions within a reversal or multielement design, then these results are often described as showing the maintenance effects of treatment. For example, Harding, Wacker, Berg, Winborn-Kemmerer et al. (2009) described a case example showing that, initially, improved behavior occurred early in treatment only when treatment was in place. If treatment was removed, then problem behavior recurred. Wacker et al. (2011) subsequently showed that similar “reversals” occurred even after relatively long periods of treatment.

Data such as these are important for showing the initial effects of treatment in that they clearly identify that improvements in behavior occur only with the provision of treatment. However, they also show that the effects of treatment are fragile, that destructive behavior will often revert to baseline levels unless treatment is continued (Volkert, Lerman, Call, & Trosclair-Lasserre, 2009), and that this will occur even after relatively long periods of treatment. This phenomenon of resurgence (Lattal & St. Peter-Pipkin, 2009; Lattal & Wacker, 2015), in which problem behavior quickly recurs even following periods of treatment, is a relatively common problem in applied situations (St. Peter-Pipkin, Vollmer, & Sloman, 2010) and is often considered as a treatment fidelity issue. That is, resurgence of problem behavior often occurs because of problems with the implementation of treatment.

St. Peter-Pipkin et al. (2010) further discussed that different types of fidelity problems can have differential effects on resurgence. Specifically, they showed that errors of commission (e.g., reinforcing problem behavior) may be more strongly related to resurgence than are errors of omission (e.g., not reinforcing appropriate behavior). Related to our projects, Suess et al. (2014) evaluated the fidelity with which the parents implemented FCT when all coaching was provided via telehealth. The parents practiced the procedures at least once per week when “off-session” (not live with a coach) and then research assistants coded the fidelity with which they conducted the procedures. Although numerous examples of fidelity problems occurred (with the most common error being not reinforcing appropriate behavior), the problems with fidelity did not disrupt the effects of treatment. Despite these initial findings, the occurrence of fidelity errors is cause for concern regarding the long-term maintenance of the treatment because we have often observed fidelity problems after treatment has been successful and the parents are attempting to “generalize” the treatment. The most common errors we have observed are provided in Table 5.

Table 5.

Common Fidelity Problems Emitted by Parents in Their Homes Based on Attempts to Generalize the Procedures to New Situations

Fidelity Problem Examples
1. Stops using treatment signals such as timers, visual schedules/cards, or communication devices because the child “knows” the procedures.
2. Uses a new demand or task because the child was successful with a previous task, even though the new task may be much less preferred or much more difficult than the original task and demand/preference fading has not occurred.
3. Positive reinforcers such as attention or leisure activities are not provided on “break” or are of a lesser quality/frequency because the parent is tired or the leisure activities cannot be found or are broken.
4. Instructions or prompts are not provided because it is expected the child can complete the task independently.
5. Chaining multiple tasks together without breaks in between because the child is doing well and it is thought he/she can do more even though demand fading has not occurred.
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Problems with treatment fidelity, such as those presented in Table 5, might be considered as challenges to the effects of treatment and specifically to the maintenance of the effects of treatment. As discussed by Nevin and Wacker (2013), maintenance might be defined when the effects of treatment persist even when challenges to treatment occur. For example, Nevin and Wacker presented a case example in which a young child displayed destructive behavior maintained by escaping demands. The treatment, FCT, was shown to have immediate effects in that a reduction in destructive behavior and an increase in task completion and manding occurred very quickly. However, when task completion and manding resulted in even brief periods of extinction, destructive behavior quickly recurred, demonstrating what may occur if a care provider is not able to respond to a targeted mand the moment it is emitted. For example, what would occur if the parent was unable to respond to a request to play for a minute or two while attending to another task or child in the home? Under such circumstances, Nevin and Wacker showed that the problem behavior immediately came back. This is obviously not desirable, and would constitute a significant problem for the parent. This would be especially problematic if the parent had thought that the treatment was successful (e.g., low frequencies of problem behavior were occurring during the treatment sessions). These brief periods of extinction are likely to be very common in most homes (and schools) and so it would be more desirable for the mand to persist and problem behavior to remain low under periods of brief extinction.

One implication of these findings is that treatment may need to be continued for much longer periods of time before the effects of treatment are shown to persist when challenged. The need for long-term treatment was shown by Wacker et al. (2011), who defined maintenance as occurring when the effects of treatment (high, steady-state responding of adaptive behavior and low, steady-state responding of problem behavior) persist even when the treatment is challenged. Our initial analysis of maintenance, based on the theory of behavioral momentum (Nevin, 1992), evaluated how both adaptive and problem behavior reacted when treatment was briefly terminated, that is, when destructive behavior, task completion, and manding were placed on extinction for 5 min. As discussed by Nevin and Shahan (2011), the display of operant behavior occurs because of two components: (a) the rate of reinforcement contingent on the behavior, and (b) the total amount of reinforcement that occurs within a specific context. The rate of reinforcement for a specific response, and the total amount of reinforcement provided within a specific context combine to strengthen the behavior. Unfortunately, they also strengthen all behaviors that are within the same context or maintained by the same class of reinforcement. Thus, the differential reinforcement of appropriate behavior within a specific context (e.g., completing a specific demand at home with mom) not only strengthens the appropriate behaviors of task completion and manding, but also the inappropriate behaviors that are also maintained by the same reinforcers (Mace et al., 2010). As conceptualized by Nevin and Wacker (2013), appropriate behavior is gradually strengthened via reinforcement over repeated treatment trials to the point that it persists when challenged, and problem behavior is weakened via extinction to the point that it fails to show resurgence. Wacker et al. (2011) conducted these brief extinction challenges intermittently throughout the long-term course of treatment with 8 children. The overall results showed that the longer the treatment was in place (i.e., task completion and manding were reinforced and destructive behavior was on extinction), the greater the persistence of treatment effects during brief periods of extinction. Although FCT often resulted in very quick reductions in destructive behavior, resurgence of destructive behavior also occurred quickly for most children. However, resurgence typically occurred early in treatment rather than later in treatment. One implication of these results is that to program for durable changes in behavior, applied behavior analysts need to increase the length of time behavior receives treatment. Although reductions in destructive behavior are a necessary component of maintenance, they are not sufficient. Instead, treatment should continue until adaptive behavior persists and destructive behavior fails to show resurgence when treatment is challenged. The goal, then, is for the strength of appropriate behavior to be much stronger than the strength of problem behavior. Because problem behavior will often have a longer and richer reinforcement history than appropriate behavior, the length of treatment may be much longer than is suggested currently in the literature.

The type of challenges to evaluate during treatment depends on the context of treatment. One way to identify challenges is to determine the “fidelity” problems that care providers or staff will most likely encounter with the treatment. Rather than waiting for those fidelity problems to occur, we suggest that they be programmed directly into the evaluation plan as probes to determine if they disrupt the effects of treatment. In our fourth project (Wacker et al., 2004; Wacker et al., 2011), we conducted a three-phase analysis of treatment (see Table 6). In the first phase, we showed the initial effects of treatment. In this context, “initial” was not time based but instead was based on the persistence of treatment effects (Dube, Ahearn, Lionello-DeNolf, & McIlvane, 2009). Thus, we used a reversal design to compare the effects of treatment to a baseline condition (extinction). During this phase, we were identifying if the FCT treatment reduced problem behavior and improved appropriate behavior during the FCT treatment condition versus a baseline condition in which all behavior was placed on extinction. The reversal design permitted us to show that FCT successfully reduced treatment, and baseline showed that the results of treatment did not persist. Because the results did not persist, we moved to Phase 2, in which we continued to compare appropriate and problem behavior during FCT and baseline within a reversal design until problem behavior remained low even during the baseline extinction condition, and appropriate behavior remained high and stable. Thus, in the second phase, we continued treatment until the effects of treatment persisted during brief periods of extinction. Treatment continued in Phase 2 until brief periods of extinction no longer disrupted behavior (reversals in behavior were not achieved). In the third phase, maintenance was evaluated by assessing the effects of changes in antecedents (e.g., types and length of tasks, augmentative communication systems) and consequences (reinforcement schedules) for both adaptive and destructive behaviors (Wacker et al., 2011). We selected these challenges because they appeared to represent fidelity problems that would likely occur in most home settings. For example, a new task might be required, the augmentative communication system might not be available, or family members might reinforce problem behavior. During this phase, conducted within a multielement design, we determined which of these common treatment challenges disrupted the persistence of appropriate behavior and/or led to the resurgence of problem behavior. In order for the effects of FCT to be durable over time, the treatment effects must persist even when these challenges occur, and these probes informed us as to which challenges we needed to include in additional treatment sessions. Evaluating the persistence of the effects of treatment may also provide information on the selection of treatments. Some treatments may produce greater persistence of adaptive behavior than other treatments or may reduce the probability of the resurgence of destructive behavior (Mace et al., 2010). For example, treatments that weaken problem behavior via extinction in addition to reinforcing appropriate behavior may result in greater long-term maintenance than do treatments that either exclusively reinforce appropriate behavior or place problem behavior on extinction. If maintenance is achieved, at least in part, by the relative strength of appropriate and problem behavior, then it makes intuitive sense to have both extinction and reinforcement components in place from the beginning of treatment. This is one example of how applied research on challenging behavior can be shaped by behavioral momentum theory.

Table 6.

Phases of FCT Treatment Analysis

Phase Description Analysis
1. Initial effects of treatment Conduct FCT to show reductions in destructive behavior and improvement in adaptive behaviour Conduct a baseline treatment condition comparison within a reversal design
2. Long-term effects of treatment Continue to probe behavior during baseline conditions to show persistence of treatment effects Continue with above analysis until reversal is not achieved
3. Maintenance of treatment effects across treatment challenges Probe likely ,fidelity- problems to identify disruptions in treatment. Increasing the length of tasks, changing the tasks, removing the communication system, and changing the reinforcement schedule are likely challenges to most FCT treatments Conduct multielement or reversal analyses to show the effects of each challenge
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In summary, we suggest defining maintenance as the persistence of treatment effects when treatment is challenged. By persistence, we are referring to the continuation of adaptive behavior and the lack of resurgence of problem behavior. The most common method of testing persistence in the existing literature is extinction (e.g., manding no longer produces reinforcement). However, a number of distinct environmental challenges can be tested, with the suggestion being to choose challenges that appear to be treatment fidelity problems. By defining and testing maintenance as suggested in this article, we can begin to program explicitly for maintenance because we will have identified the conditions under which maintenance occurs. Maintenance, then, becomes a distinct phase from treatment and can be analyzed experimentally to identify functional relations.

Acknowledgments

Author note: This investigation was supported by Grant R01 HD029402 from the National Institute of Child Health and Human Development of the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Child Health and Human Development or the National Institutes of Health. The authors express their appreciation to the families who participated in this investigation and to Agnes DeRaad for her assistance with manuscript preparation.

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