Measuring sleep habits using the Sleep Timing Questionnaire: A validation study for school-age children

In 2003 Monk and colleagues published a single-administration replacement for a standard sleep diary, the Sleep Timing Questionnaire (STQ). Reliable and valid for adult participants, it offers advantages over existing methodologies in cost and convenience. It takes approximately 10 min to complete but can yield information equivalent to a week of actigraphy, or a 2-week sleep diary. This study sought to validate the STQ for school-age children. Sixty-five children (20 boys, 45 girls), aged 11-16 years participated in this study. The participants wore wrist actigraphs, completed a 1-week sleep diary and the STQ. Analyses tested convergent validity between the STQ and actigraphy, and the STQ and sleep diaries. Correlations between STQ and actigraphy (r = 0.45-0.76, P < 0.001), and STQ and sleep diaries (r = 0.42-0.86, P < 0.001), were positive and significant for sleep onset and wake times. Correlations between STQ and actigraphy for sleep latency and wake after sleep onset (WASO) were very low (r < 0.10). In contrast, sleep latency was moderately and significantly correlated between STQ and sleep diary (r = 0.42, P < 0.001), and the correlation for WASO was high and significant (r = 0.74, P < 0.001). Differences between the STQ and sleep diary were within acceptable limits for all sleep parameters, and the differences between STQ and actigraphy were acceptable for sleep onset and school day wake time. The STQ may be a valid indicator of sleep onset and wake time in school-age children. It can also produce measures of sleep latency and WASO with comparable accuracy to a standard sleep diary. © 2010 The Authors. Journal compilation © 2010 Japanese Society of Sleep Research.