Table 1 Demographic and menstrual characteristics of the participants
From: Health-related quality of life among Chinese adolescent girls with Dysmenorrhoea
|  | Total sample (n = 653) | With dysmenorrhea (n = 428) | Without dysmenorrhea (n = 225) | p-value |
|---|---|---|---|---|
Age (years) | ||||
 Mean (SD) | 15.67 (1.54) | 15.82 (1.56) | 15.40 (1.50) | < 0.001a |
Height (cm) | ||||
 Mean (SD) | 159.32 (5.79) | 159.39 (5.66) | 159.16 (6.04) | 0.62a |
Weight (kg) | ||||
 Mean (SD) | 48.25 (7.24) | 48.10 (7.14) | 48.53 (7.44) | 0.48a |
BMI | ||||
 Mean (SD) | 19.00 (2.63) | 18.91 (2.47) | 19.12 (2.91) | 0.25a |
Family income (HK$) | ||||
  < 5000 | 20 (3.1) | 12 (2.8) | 8 (3.6) | 0.27b |
 5001–10,000 | 136 (20.8) | 80 (18.7) | 56 (24.9) |  |
 10,001–20,000 | 246 (37.7) | 166 (38.8) | 80 (35.6) |  |
 20,001–30,000 | 146 (22.4) | 94 (22.0) | 52 (23.1) |  |
  > 30,001 | 105 (16.1) | 76 (17.8) | 29 (12.9) |  |
Age at menarche (years) | ||||
 Mean (SD) | 12.07 (2.23) | 12.06 (1.00) | 12.14 (1.07) | 0.33a |
Menstrual cycle (days) | ||||
 16–20 | 47 (7.2) | 29 (6.8) | 18 (8.0) | 0.44b |
 21–25 | 137 (21.0) | 97 (22.7) | 40 (17.8) |  |
 26–30 | 262 (40.1) | 165 (38.6) | 97 (43.1) |  |
 31–35 | 105 (16.1) | 74 (17.3) | 31 (13.8) |  |
 36-40 | 45 (6.9) | 31 (7.2) | 14 (6.2) |  |
  ≥ 40 | 57 (8.8) | 32 (7.5) | 25 (11.1) |  |
Menstruation duration (days) | ||||
 Mean (SD) | 5.60 (1.08) | 5.60 (1.10) | 5.61 (1.12) | 0.93a |
Amount of menstruation | ||||
 Small | 42 (6.4) | 24 (5.6) | 18 (8.0) | 0.30b |
 Moderate | 528 (80.9) | 345 (80.6) | 183 (81.3) |  |
 Large | 83 (12.7) | 59 (13.8) | 24 (10.7) |  |