Changes of Adult Population Health Status in China from 2003 to 2008

Sun, Hongpeng; Zhang, Qiuju; Luo, Xiao; Quan, Hude; Zhang, Feng; Liu, Chang; Liu, Meina

There are four major limitations to this study. A major limitation is that data were collected through two cross-sectional surveys, whereas the two questionnaires did not have precisely the same structure. Also, the cross-sectional nature allows for errors in recall. A second limitation is that the present study was based on observational data; therefore we cannot be completely sure of the association between demographic characteristics and health status, even after controlling for potential confounders. A third limitation is that we only analyzed seven major risk factors but were unable to assess other important risk factors of diet and obesity. The fourth major limitation is that the prevalence of chronic disease was likely underestimated because only physician-diagnosed chronic disease in the last 6 months was recorded. However, this study mainly explored relative change for presence of chronic disease from 2003 to 2008. Some bias in both cross-sectional surveys could be offset to some extent.