Stratified analyses by potential modifiers of the association between number of cognitive activities and all-cause mortality.

Note: Each stratification with adjustment for all factors (sex, age, education, marital status, residence, co-residence, regular intake of fruits, regular intake of vegetables, regular intake of meats, current smoking, current drinking, current regular exercise, hypertension, diabetes, heart diseases, cerebrovascular diseases, respiratory diseases, cancer, and self-rated health) except the stratification factor itself. (PDF)