| Methods |
Randomized controlled trial without blinding. The method of randomization and the use of allocation concealment are not described. We were unable to reach the authors. |
| Participants |
2419 women in 18 countries worldwide. Inclusion criteria were age 18 to 41 years who had regular menstrual cycles. Exclusion criteria were hypersensitivity to estrogens or progestogens, current pregnancy, breastfeeding, disorders that might interfere with the study protocol. Little information about baseline demographics. The paper does not report if switchers were included in the study. |
| Interventions |
Triphasic gestodene/ethinylestradiol (50‐70‐100 μg GTD and 30‐40‐30 μg EE in a 6/5/10 days regimen, N=808) [Tri‐Minulet] versus
monophasic gestodene/ethinylestradiol (75 μg GTD and 30 μg EE for 21 days, N=806) [Minulet] versus
monophasic desogestrel/ethinylestradiol (150 μg DSG and 20 μg EE for 21 days, N=805) [Mercilon]. |
| Outcomes |
Primary outcome measures are: cycle control; well‐being; side effects and discontinuation. Use of a daily diary card to collect data on cycle control. Use of a modified form of Moos Menstrual Distress Questionnaire (MMDQ) to assess well‐being. The method of collecting data on side effects is unclear. The report does not describe the definitions of breakthrough bleeding and spotting. |
| Notes |
The report does not describe an a priori hypothesis or sample size or power calculation. Study duration: 13 cycles. 234 women in the triphasic group, 245 women in the monophasic gestodene group and 219 women in the monophasic desogestrel group discontinued early. The reasons for discontinuation are described. 92 women in the triphasic group, 101 women in the monophasic gestodene group and 77 women in the monophasic desogestrel group were lost to follow up. 17 women in the triphasic group, 15 women in the monophasic gestodene group and 10 women in the monophasic desogestrel group were withdrawn because of protocol violations. Analysis not according to intention‐to‐treat principle. The trial was sponsored by the manufacturer of the studied triphasic and monophasic gestodene/ethinylestradiol pills (Wyeth‐Ayerst) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Allocation concealment (selection bias) |
Unclear risk |
No information |
