Joint analysis on day napping and night sleeping in relation to the risk of diabetes after 2000. Multivariate ORs for diabetes were adjusted for age, sex, race, education, marital status, smoking status, coffee and alcohol consumptions, calorie intake, family history of diabetes, general health status, light physical activity level, moderate to vigorous physical activity level, and BMI. The subgroup Ptrend in the napping analyses was 0.02 for participants with <5 h of night sleep, 0.002 for participants with 5–6 h of night sleep, <0.001 for participants with 7–8 h of night sleep, and 0.006 for participants with ≥9 h of night sleep.