Circadian rhythms behind interviewers' approaches: the time‐of‐day effect in police interviews with children

Police interviews with children are often the only source of evidence about an abuse. Circadian rhythms are known to affect cognitive processes, but the effect they may have on the quality of police interviews is unknown. Data comprised 102 transcriptions of police interviews with children. Transcripts were rated for effective interviewing approaches, that is approaches following guidelines. Time of day was examined as a predictor of interviewers effectiveness related with the type of approaches interviewers used, for example, open-ended questions. Interviewer effectiveness declined as the day progressed, but only for the less skilled interviewers. Highly skilled interviewers were unaffected by the time-of-day. The identification of time-of-day as a possible risk factor which reduces the quality of interviews is of great importance.