Table 2

 Odds ratio (OR) and 95% confidence interval (CI) for dysmenorrhoea in association with self perceived stress during the preceding menstrual cycle in 388 Chinese women

Stress in the preceding cyclesTotal cycles† (% dysmenorrhoea)OR‡95% CI
†1160 cycles chosen from 388 subjects were included in this analysis.
‡The outcome was defined as a binary variable adjusted for age, BMI, shift work, dust exposure, cycle length, education, and passive smoking.
§Reference group.
Low494 (21.9)1.0§
Medium495 (28.7)1.20.8 to 1.7
High171 (43.9)2.41.4 to 4.3**