A Comparison of Self- and Proxy-Reported Subjective Sleep Duration with Objective Actigraphy Measurements in a Survey of Wisconsin Children Aged 6-17 Years Old.

Children's sleep quality and duration are important to overall development, health, and wellbeing. However, measuring children's sleep is challenging - especially in situations where objective assessment is impractical. This study aimed to assess age and proxy effects in comparing subjective sleep duration with objective measures, in a community-based sample of Wisconsin children (age 6-17 years), recruited from 2014-2017. The sample mean age was 11.4 years (SD: 3.3 years) and was 52% male. We used linear mixed effects models to test for age effects in proxy- and self-report groups separately, and a quasi-experimental regression discontinuity approach to compare subjective sleep duration with objective actigraphy estimates across proxy- and self-report groups. We found evidence of systematic overestimation of sleep duration when using subjective measurements but did not find evidence of age effects in either group. Based on these analyses, we found evidence of differential overestimation by proxy- or self-report condition; proxy-reporters overestimated sleep duration by 2.3 hours (95% CI: 2.2, 2.4), compared to 1.0 hour (95% CI: 0.7, 1.2) for self-reporters. These findings suggest that proxy- versus self-reporting conditions are an important consideration when designing a study, and that it may be beneficial to reduce the age at which children self-report.