Table 4. Respondent’s health situation in 2014 in ZhongShan ($\overline{\text{x}}$ ±s).

	Registered population	Internal migrants	Years of residence of internal migrants
			Level1	Level2	Level3	Level4	Level5	Level6	Level7	Level8
Self-reported health	21.43±3.95	22.31±3.86***	21.41±3.56	21.82±3.57	22.10±3.57*	22.46±3.89**	22.10±4.36	22.37±3.93*	22.83±3.92*	22.98±4.09*
subjective well-being	22.03±6.23	21.53±5.86**	22.21±5.58	22.11±5.06	21.40±5.59	21.30±6.23	21.03±5.73	21.13±5.61	22.00±6.23	22.35±6.34
perception of stress	14.20±2.54	13.96±2.49**	13.56±2.34**	13.55±2.30**	13.65±2.11**	13.92±2.52	14.16±2.42	13.86±2.57	14.28±2.70	14.59±2.70
Mental health	26.36±3.16	26.43±3.07	26.17±3.32*	26.11±3.35	26.52±2.91	26.56±2.98	26.54±2.71	25.87±3.53	26.59±3.04	26.66±2.82

* p<0.05;

** p<0.01;

*** p<0.001