Validation of the National Health And Nutritional Survey (NHANES) single-item self-reported sleep duration against wrist-worn accelerometer.

PURPOSE AND METHODS This study aimed to validate the single-item sleep duration question used in the National Health And Nutritional Survey (NHANES), "How much sleep do you usually get at night on weekdays or workdays (hours)?", against a wrist-worn accelerometer (ActiGraph GT3X +) in waves 2011-2012 and 2013-2014 among an adult population aged 20 or above (n = 8,438, mean age 49.7, 48% male). RESULTS The accelerometer-measured and self-reported sleep duration were 6.01 (SD 1.48) and 6.88 (SD 1.40) h/day, respectively, representing a 0.87 h/day of over-reporting (SD 1.90, p < 0.001). Such an over-reporting was observed in all subgroups, where the over-reporting ranged from 0.72 (those aged 41-50) to 1.13 h/day (those aged 71 or above). The correlation between accelerometer-measured and self-reported sleep duration was low (ρ = 0.14, p < 0.001). CONCLUSIONS The associations between sleep duration and other health outcomes identified using NHANES data should be further tested using more accurate and valid measures of sleep duration.