ANALYTIC METHODS
The SF-36 was scored using the Japanese 1.2 version
of the SF-36 manual (7). For each subscale of the
SF-36, a one-way analysis of variance (ANOVA) was
employed to compare group means. When overall differences
were found by ANOVA, pair-wise comparisons
of group means were conducted using t-tests.
Correlations among subscale items and other study
variables were examined using the Spearman rank
correlation. The scores of the subjects on the SF-36
subscales were compared to the scores of a national
reference population (8). A p value of less than 0.01
was considered significant in all data analyses.