Development and evaluation of a questionnaire for measuring suboptimal health status in urban Chinese.
BACKGROUND
Suboptimal health status (SHS) is characterized by ambiguous health complaints, general weakness, and lack of vitality, and has become a new public health challenge in China. It is believed to be a subclinical, reversible stage of chronic disease. Studies of intervention and prognosis for SHS are expected to become increasingly important. Consequently, a reliable and valid instrument to assess SHS is essential. We developed and evaluated a questionnaire for measuring SHS in urban Chinese.


METHODS
Focus group discussions and a literature review provided the basis for the development of the questionnaire. Questionnaire validity and reliability were evaluated in a small pilot study and in a larger cross-sectional study of 3000 individuals. Analyses included tests for reliability and internal consistency, exploratory and confirmatory factor analysis, and tests for discriminative ability and convergent validity.


RESULTS
The final questionnaire included 25 items on SHS (SHSQ-25), and encompassed 5 subscales: fatigue, the cardiovascular system, the digestive tract, the immune system, and mental status. Overall, 2799 of 3000 participants completed the questionnaire (93.3%). Test-retest reliability coefficients of individual items ranged from 0.89 to 0.98. Item-subscale correlations ranged from 0.51 to 0.72, and Cronbach's alpha was 0.70 or higher for all subscales. Factor analysis established 5 distinct domains, as conceptualized in our model. One-way ANOVA showed statistically significant differences in scale scores between 3 occupation groups; these included total scores and subscores (P<0.01). The correlation between the SHS scores and experienced stress was statistically significant (r=0.57, P<0.001).


CONCLUSIONS
The SHSQ-25 is a reliable and valid instrument for measuring sub-health status in urban Chinese.
Yan
Yu-Xiang
YX
School of Public Health and Family Medicine, Capital Medical University, Physical Examination Center, Beijing Xuanwu Hospital, Beijing, China.
Liu
You-Qin
YQ
Li
Man
M
Hu
Pei-Feng
PF
Guo
Ai-Min
AM
Yang
Xing-Hua
XH
Qiu
Jing-Jun
JJ
Yang
Shan-Shan
SS
Shen
Jian
J
Zhang
Li-Ping
LP
Wang
Wei
W
D000293:Adolescent; D000328:Adult; D002681:China; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D014505:Urban Population; D055815:Young Adult