Demographic characteristics and scores of Chinese migrants among different SMEs (n = 856).

P≤0.05, **P≤0.01, ***P≤0.001, △P≤0.05 (compared with the first option),▽P≤0.05 (compared with the second option), □P≤0.01 (compared with the second and third option).: the statistics for chi-squared test; t: the statistics for t-test; F: the statistics for Analysis of variance (ANOVA); PCS: physical component summary; MCS: mental component summary; h: hour; ¥: the currency symbol of RMB.Note: Most of the variables' categories follow the national migrants' survey [3]. the mean age of Chinese migrants were 27.9 in 2011,thus the age variable was divided into two categories (>27.9 and ≤27.9). The monthly income of migrants was divided into four group “