Table 5

ORs for dysmenorrhoea according to consumption of type of tea beverage/caffeinated beverage

VariablesCrude OR modelAdjusted OR model
No (486)Mild (574)Moderate-to-severe (92)Mild (574)Moderate-to-severe (92)
Model 1*
 Green tea10.74 (0.56 to 0.97)0.61 (0.35 to 1.05)0.63 (0.44 to 0.90)0.42 (0.20 to 0.85)
 Black tea11.09 (0.78 to 1.53)1.38 (0.78 to 2.44)1.27 (0.81 to 2.00)1.96 (0.94 to 4.10)
 Oolong tea10.73 (0.48 to 1.10)0.38 (0.13 to 1.08)0.60 (0.35 to 1.03)0.34 (0.11 to 1.09)
Model 2
 Coffee11.06 (0.83 to 1.35)2.22 (1.40 to3.52)1.08 (0.80 to 1.44)2.11 (1.22 to 3.62)
 Soda11.12 (0.87 to1.45)1.78 (1.13 to 2.81)1.05 (0.76 to 1.44)1.20 (0.69 to 2.10)
 Energy beverages11.25 (0.73 to 2.13)2.61 (1.23 to 5.54)0.91 (0.50 to 1.69)1.65 (0.66 to 4.15)
  • *Model 1 was a multinomial logistic regression model which was used for each type of tea beverage separately, and was further adjusted for other types of tea beverages, age, body mass index (BMI), personal income, ever pregnant, caffeinated beverages drinking, alcohol drinking now and during last 1 year, secondhand smoke, supplementation of fish oil, consumption of leaf vegetables, moderate-intensity and walk-intensity physical activity.

  • †Model 2 was a multinomial logistic regression model which was used for each caffeinated beverage separately, and was further adjusted for other caffeinated beverages, age, BMI, personal income, ever pregnant, secondhand smoke, walk-intensity physical activity and tea drinking.