Who's up first? Testing for order effects in structured interviews using a counterbalanced experimental design.

A growing body of research suggests that, apart from the wording of specific questions, various aspects of the interview process itself may affect the reliability of information provided by research participants. To examine whether the order of presentation of specific diagnostic modules affects the likelihood of subjects' yes/no responses within the Diagnostic Interview Schedule for Children (DISC), the authors used a counterbalanced design, presenting two DISC diagnostic modules to children and their parents in standard or reversed order. Results indicate that the order of module administration exerts effects on the total numbers of symptoms endorsed, level of impairment, and the likelihood of meeting diagnostic criteria, regardless of whether the information is provided by parent or child respondents. Future child and adult assessment measures should take these difficulties fully into account through novel approaches to instrument design and interview procedures.