Data were recorded by Epi-Info. for windows,
Taxas, USA 2007 by method of doubledata entry,
analysis by STATA Version 10 (Khon Kean
University’s Copy Rights). Descriptive statistics
were used to describe the characteristics and sixmonth
prevalence of RSIs. The associations of the
developing RSIs with several individual factors,
health status as well as a set of physical risk factors
were examined by Chi-square tests or Fisher’s exact
tests, whichever were more appropriate. Factors
with p-value less than 0.25 in chi square tests or
Fisher’ s exact were selected to be candidate
variables in multiple logistic regression models.
Significant risk factors were screened in a backward
stepwise manner using likelihood ration tests as a
selection criterion. Odds ratio (OR) and 95%
confident interval (95% CI) were presented and pvalue