Statistical Analysis
REGRESSION, CVD
Comparisons of baseline characteristics are presented as mean±SD for continuous variables and number (percentages) for categorical variables. Differences in the characteristics were analyzed using chi‐square test for categorical variables and independent Student Restricted cubic spline Cox regression was applied to assess the dose–response association of objective and self‐reported sleep duration with all‐cause and CVD mortality (5 knots at the 5.0th, 27.5th, 50.0th, 72.5th, and 95.0th percentiles). Pearson correlation was used to determine the correlation between objective and self‐reported sleep duration. All statistical analyses were performed using SPSS statistics software (version 24.0, IBM) and R software version 3.6.3 (R Core Team). All statistical significance was 2‐sided, and a 