Autism spectrum disorder (ASD) is characterized by restricted, repetitive, and stereotyped behaviors and impairments in social communication and social interaction, (American Psychiatric Association 2013
), including deficits in self-initiations and question-asking. Compared with typically developing children, children with ASD ask fewer questions and their questions serve fewer functions (Hauck et al. 1995
; Stone and Caro-Martinez 1990
; Stone et al. 1997
; Wetherby and Prutting 1984
). This results in reduced opportunities for learning a variety of skills as they elicit fewer teaching interactions from their environment (Koegel et al. 2003
; McDuff et al. 2001
). Furthermore, deficits in question-asking often lead to directive behavior of children’s environment, thereby further reducing their opportunities to self-initiate questions (Hudry et al. 2013
). Deficits in question-asking are associated with poorer long-term outcomes on pragmatic and adaptive skills and school and community functioning (Koegel et al. 1999
). For these and other reasons, it is important to teach children with ASD to initiate questions.
Numerous studies have reported on interventions aimed at teaching question-asking skills to children with ASD. Targeted questions had various communicative functions, including requesting objects (e.g., Wert and Neisworth 2003
), help (e.g., Dotto-Fojut et al. 2011
), information (e.g., Betz et al. 2010
), and social information (e.g., Dogget et al. 2013
). These studies encompassed multicomponent behavioral interventions to increase question-asking, for example discrete trial teaching (DTT; e.g., Ingvarsson and Hollobaugh 2010
), pivotal response treatment (PRT) (e.g., Koegel et al. 2014
), self-management (e.g., Koegel et al. 2014
), and video modeling (e.g., Charlop and Millstein 1989
). Common components included contrived establishing operations, systematic prompting (e.g., echoic prompts) and prompt fading procedures (e.g., time delay) and natural reinforcement (Raulston et al. 2013
). A systematic review reported positive results of these components with regard to the acquisition of targeted questions, suggesting that these components are effective in teaching question-asking skills to children with ASD (Raulston et al. 2013
). However, the effectiveness of these components has not yet been investigated during intervention sessions in the context of natural everyday activities, conducted by children’s natural conversational partners, and targeting questions with various communicative functions. Moreover, generalization effects of question-asking interventions to natural situations were rather limited (e.g., Betz et al. 2010
). Deficits in question-asking in natural situations may thus reflect a performance deficit rather than a skill deficit (Koegel et al. 2012
; Palmen et al. 2008
). To bring question-asking under control of natural stimuli, children with ASD should preferably be taught question-asking skills directly in natural situations by natural conversational partners who need training to implement interventions with adequate treatment fidelity (e.g., Reid and Fitch 2011
Pivotal response treatment may be indicated, because training in the child’s natural environment is a critical component of PRT (Koegel and Koegel 2006
). PRT is an intervention model derived from the principles of applied behavior analysis (ABA) that targets pivotal skills (e.g., self-initiations) in children with ASD in order to achieve generalized improvements in their functioning. A systematic review found evidence for the effectiveness of PRT for increasing self-initiations including question-asking in children with ASD (see Verschuur et al. 2014
). Furthermore, evidence for generalized improvements in language, communication, play, affect and maladaptive behavior as a result of PRT was reported. However, studies on the effectiveness of PRT on question-asking skills have several limitations. First, although training children in their natural environment is a key component of PRT, in studies where PRT was implemented to improve question-asking skills, PRT sessions were usually not conducted during natural everyday activities (e.g., Koegel et al. 2010
) and PRT was not implemented by children’s natural conversation partners (e.g., Doggett et al. 2013
). Second, the effectiveness of PRT has mainly been investigated in preschool children with ASD (e.g., Koegel et al. 2003
). The few studies that investigated the effectiveness of PRT on self-initiations (including asking questions) in school-aged children with ASD reported either positive results (e.g., Dogett et al. 2013
; Robinson 2011
) or mixed results (e.g., Huskens et al. 2012
). They also failed to measure gains in collateral skills. The latter is important because PRT assumes that collateral skills improve as a result of the acquisition of pivotal skills. Third, the effectiveness of PRT on question-asking has not yet been investigated in children with ASD receiving inpatient treatment. This may be viewed as a limitation as approximately 6% of children with ASD receive inpatient treatment (e.g., Cidav et al. 2013
), predominantly because of psychiatric comorbidity, aggressive behavior, self-injurious behavior, and impaired emotion regulation (Mandell 2008
; Siegel and Gabriels 2014
). It is unclear whether PRT is effective for school-aged children who are admitted to an inpatient facility and whether their staff is able to implement PRT in daily one-to-one situations.
This study aimed to investigate (a) effectiveness of PRT staff training on staff member-created opportunities, (b) effectiveness of PRT on self-initiated questions of school-aged children with ASD during everyday activities in one-to-one situations, (c) generalization of these skills to group situations, and (d) maintenance of these skills over a 6-month period. Furthermore, collateral changes in children’s language, pragmatic, and adaptive skills and maladaptive behaviors were explored.
In the present study, staff members of an inpatient treatment facility in the Netherlands for school-aged children with ASD were taught to create opportunities for question-asking through staff training in PRT. Eleven of the 14 staff members created significantly more opportunities during intervention, indicating that staff training in PRT is effective for this purpose. However, generalization of creating opportunities to group situations was limited. Post-intervention and follow-up data demonstrated that most staff members maintained their skills over time. Furthermore, 8 of the 14 children initiated significantly more questions as a result of intervention. However, only a minority of the children maintained these skills over time. Generalization of child-initiated questions to group situations and collateral changes in language, pragmatic and adaptive skills and maladaptive behaviors did not occur.
The present study confirms findings of Huskens et al. (2012
) indicating that staff can be taught to create opportunities for question-asking using PRT. Furthermore, this study adds to the growing evidence base supporting the use of PRT to improve question-asking in school-aged children with ASD (e.g., Dogget et al. 2013
; Huskens et al. 2012
; Robinson 2011
). Until now, studies targeting question-asking focused on the acquisition of questions within only one communicative function (e.g., Betz et al. 2010
; Dogget et al. 2013
). The present study extends these studies by showing that children with ASD can acquire multiple questions with various communicative functions in the context of natural daily activities.
Both staff members and children with ASD did not generalize the targeted skills to group situations. Research on implementation of PRT in group situations is limited, but studies in school settings have indicated that PRT techniques need to be adapted for implementation in classrooms and that teachers required additional training to be able to implement PRT in group settings with multiple children (Stahmer et al. 2012
), suggesting that staff members also may require additional skills and training to create opportunities and implement PRT in group situations. Because of limited generalization of staff members’ skills it is not surprising that children’s question-asking skills did not improve in group situations. This suggests that children relied on staff members’ cues and prompts to initiate questions in these situations. Self-management might be helpful to promote generalization of question-asking to situations where staff members’ cues are less frequent or absent (e.g., Koegel et al. 2014
Although the number of opportunities increased for most staff members, there remained a great deal of variability in responding between staff. Staff characteristics may account for this variability (Durlak and DuPre 2008
; Peters-Scheffer et al. 2013
; Symes et al. 2005
). For example, Peters-Scheffer et al. (2013
) examined the relationship between procedural fidelity of DTT and therapist personality traits, attitude towards individuals with disabilities, and therapist-child relationship. Results indicated that procedural fidelity was significantly related to these staff characteristics. The procedural fidelity of PRT might also be associated with these and other staff characteristics. Because the sample size of the present study was too small to explore the association between procedural fidelity of PRT staff characteristics, future research should address this topic.
Similarly, intervention outcomes across children were also highly variable. This outcome variability is consistent with the results of a systematic review on PRT (Verschuur et al. 2014
) and evaluations of ABA interventions (e.g., Peters-Scheffer et al. 2011
; Reichow 2012
; Vivanti et al. 2014
). Behavioral intervention outcomes are associated with child characteristics, for example age, language proficiency, pre-intervention cognitive skills, and autism severity (e.g., Ben-Itzchak and Zachor 2011
; Perry et al. 2013
; Smith et al. 2015
). However, these characteristics do not seem to explain variability in children’s question-asking skills in the present study, because these characteristics also varied across children who did not benefit from PRT. Future research should investigate whether these and other child characteristics (e.g., psychiatric comorbidity and maladaptive behaviors) are associated with outcomes of PRT for school-aged children with ASD. In addition to variability across children, question-asking also varied across intervention sessions within individual children. This suggests that, although children might have acquired the skills to initiate questions, they are not yet able to use these skills consistently. Factors that could explain this variable performance within children are currently unknown.
Whereas other studies reported generalized improvements as a result of PRT (e.g., Baker-Ericzén et al. 2007
; Mohammadzaheri et al. 2014
), the present study did not find significant (i.e., reliable) collateral changes in children’s language, pragmatic, and adaptive skills and maladaptive behaviours, despite the fact that identical measures were used (i.e., CCC2 and Vineland-II). Different methods of data-analysis may account for these inconsistent results. Other studies analysed changes in mean scores across children, for example using paired-sample t
-tests. The present study analysed changes in collateral skills using the RCI, which represents individual changes and takes measurement errors into account (Jacobson and Truax 1991
). Exploratory paired-sample t
-tests and Wilcoxon signed-rank tests were conducted to compare results across analyses and demonstrated statistically significant improvements in children’s language, pragmatic, and overall adaptive skills. This comparison suggests that although mean scores across children might have changed significantly, these changes were smaller than the questionnaires’ standard errors of measurement and thus not reliable according to an RCI approach. Future studies investigating generalized improvements as a result of PRT should take measurement errors into account by analysing data at the individual level.
There are several limitations to the present study. First, the number of staff member-created opportunities is presumably underestimated, because only opportunities that resulted in self-initiated questions were considered correct to take the child’s motivation into account. Motivation is often defined as children’s responsiveness to social and environmental stimuli (Koegel et al. 2001
). If staff gained the child’s attention, but the child did not ask a question, it was assumed that staff did not follow the child’s motivation and no opportunity was scored. However, this could have led to an underestimation of the number opportunities. Second, all questions were coded as self-initiated questions and no distinction was made between self-initiated questions with different communicative functions, although social questions (e.g., ‘How was your weekend?’)
have more potential to improve children’s social success than functional questions (e.g., ‘Can I have the blocks?’). Third, baseline trend was positive for ten children. This suggests that children’s question-asking skills might improve without PRT, but it could also be possible that staff members unintentionally or naturally implemented some antecedent or consequent PRT techniques during baseline, for example by responding to children’s spontaneous questions (e.g., Raulston et al. 2013
). Fourth, due to high level of attrition follow-up sessions were conducted for only five children. Results concerning maintenance of question-asking skills should thus be interpreted with caution. Fifth, because the researcher collected generalization probes, reactive effects could have occurred during these probes (Cooper et al. 2013
). Similarly, increases in staff member-created opportunities during baseline, post-intervention, or follow-up could be a result of increased monitoring, because staff members were instructed to record these sessions and were thus aware of being observed. Finally, collateral skills were measured using questionnaires. In order to gain more objective data, however, direct assessment methods such as observation can be considered more suitable to measure behavior change (Cooper et al. 2013
Despite these limitations, the results of this study are promising as they indicate that PRT staff training is effective in teaching inpatient staff to create opportunities for question-asking. Moreover, question-asking skills of some school-aged children with ASD improved as a result of PRT. Further research is necessary to investigate training procedures that promote generalized, consistent, and continuous implementation of PRT by staff across situations and to identify staff and child characteristics associated with fidelity of PRT implementation respectively PRT outcomes.