“…We selected the established factors that have been clearly identified in previous research as control variables for healthy aging (Appendix 2 in the Supplement), including: physical condition (chronic diseases, teeth) [ 2 – 4 , 34 , 35 , 38 , 40 ], SES (education, ACE, household income) [ 3 , 4 , 6 , 8 , 9 , 34 , 35 , 40 – 44 ], lifestyle habits (smoke, drink) [ 3 , 6 , 7 , 34 , 35 , 41 , 43 , 45 ], and demographic factors (geographical distribution, urban–rural distribution, age, gender, and marital status) [ 3 , 4 , 6 , 9 , 34 , 35 , 40 , 42 ].…”