Table 2.

Construct measurement.

Construct	Item	Measurement	Source
Use of CPE	CPE: Whether to receive community annually free physical examination?	1 = no; 2 = yes	[1]
Use of OS	OS: What will you prefer to do when you suffered from common illnesses?	1 = The other choices; 2 = Visit physicians	[4]
Migrating duration	The duration for this migration. (years)	1 ≤ 5; 2 = 5–10; 3 ≥ 10	[4]
Migrating for offspring	The reason for this migration.	1 = The other choices, 2 = Caring for offspring	[9,19]
Outer social support	S1: Do you have medical insurance?	1 = no; 2 = yes	[9,10]
	S2: Do you have local friends?	1 = no; 2 = yes
Control variable	C1: Physical health status	1 = healthy; 2 = general healthy; 3 = unhealthy
	C2: Monthly household income after tax	1 ≤ CNY 2000; 2 = CNY 2000–5000; 3 ≥ CNY 5000

OS, outpatient services; CPE, community physical examinations.