Data were derived from the 2008 National Health Services Survey (NHSS), which has been organised by the Chinese Ministry of Health (MoH) every fifth year since 1993. The surveys were carried out from mid-June till mid-July, and face-to-face interviews were conducted by trained local interviewers [45 ]. The NHSS 2008 questionnaire includes more than 200 questions, on acute diseases and injuries, chronic and other diseases, hospitalisation, health-related behaviour, educational level, family income and employment status, social relations, safety and security, medical care fees, accessibility (distance and time) and satisfaction with health service, insurance coverage, vaccination and disease control, woman and child health services. In 2008, the EQ-5D was included for the first time.
In NHSS 2008, 56,400 households were sampled using a multi-stage stratified cluster random sampling [46 ]. In the first sample stage, 2,400 counties were stratified based on socio-economic, health care and population structure to sample 94 counties. In the second stage, 2,350 streets (urban area) and townships (rural area) in the 94 counties were stratified based on population size and income per capita to sample 470 streets and townships. In the third stage, 940 residential committees (urban area) and villages (rural area) were sampled using the same criteria as in the second stage. In each residential committee or village, 60 households were randomly selected, and all family members in a sampled household were interviewed individually. EQ-5D was asked among persons aged 15 years and over, and no upper-age limit was applied. However, the instrument can be used in younger age groups, and the newly developed child-friendly version of the EQ-5D, named EQ-5D-Y [47 (link), 48 ], is available in some language versions, but not yet in Chinese. Hence, persons aged under 15 years were not included in this study.
In total, 177,501 respondents were included in NHSS 2008. Of these, about 18% aged below 15 years were excluded, since EQ-5D questions should only be administered to respondents aged 15 years and over. Respondents not answering the questions by themselves were excluded (13%). In total, less than 2% of the respondents had missing answers on age, sex, in at least one of the EQ-5D dimensions, on VAS or reported VAS higher than 100. After applying the previous exclusion criteria, 120,703 respondents were included in this study.
Ethical permission was granted by the Regional ethics committee, Stockholm, Sweden, for analyses of this study (Dnr: 2009/1892–31).
In NHSS 2008, 56,400 households were sampled using a multi-stage stratified cluster random sampling [46 ]. In the first sample stage, 2,400 counties were stratified based on socio-economic, health care and population structure to sample 94 counties. In the second stage, 2,350 streets (urban area) and townships (rural area) in the 94 counties were stratified based on population size and income per capita to sample 470 streets and townships. In the third stage, 940 residential committees (urban area) and villages (rural area) were sampled using the same criteria as in the second stage. In each residential committee or village, 60 households were randomly selected, and all family members in a sampled household were interviewed individually. EQ-5D was asked among persons aged 15 years and over, and no upper-age limit was applied. However, the instrument can be used in younger age groups, and the newly developed child-friendly version of the EQ-5D, named EQ-5D-Y [47 (link), 48 ], is available in some language versions, but not yet in Chinese. Hence, persons aged under 15 years were not included in this study.
In total, 177,501 respondents were included in NHSS 2008. Of these, about 18% aged below 15 years were excluded, since EQ-5D questions should only be administered to respondents aged 15 years and over. Respondents not answering the questions by themselves were excluded (13%). In total, less than 2% of the respondents had missing answers on age, sex, in at least one of the EQ-5D dimensions, on VAS or reported VAS higher than 100. After applying the previous exclusion criteria, 120,703 respondents were included in this study.
Ethical permission was granted by the Regional ethics committee, Stockholm, Sweden, for analyses of this study (Dnr: 2009/1892–31).
