Abstract
This study investigated the seasonality of mortality in Hong Kong from 1980 to 2005 using cosinor analysis. Mortality data from all causes of death, neoplasm, circulatory and respiratory diseases were obtained from the Census and Statistics Department. Statistically significant seasonalities were ascertained for total and gender-specific deaths from all causes, circulatory and respiratory diseases, but not neoplasm. The amplitudes of seasonal fluctuations were low. Also, amplitudes of seasonality increased with age and a conspicuous increase in amplitudes at age group ≥65 was detected. The timing of the peak for significant rhythms was in February and March.