| Methods |
'Case‐control study'. Cases were 195 women with incident epithelial ovarian cancer admitted to major teaching and general hospitals at 4 centres. Women with borderline tumours were excluded. Controls were 1339 women from the same geographical area and admitted to the same network of hospitals as cases for a wide range of acute non‐neoplastic conditions. Women with hormonal or gynaecological diseases or bilateral oophorectomy were excluded. From 1992 to 1993; multi‐centre in Italy |
| Participants |
Age range for cases was 18 to 75 (median 55); age range for controls was 19 to 79 years (median 56) |
| Interventions |
Use of 'fertility drugs', drug, dosage, and number of cycles not reported |
| Outcomes |
Epithelial ovarian cancer by histological diagnosis (see Table 2) |
| Notes |
Duration of follow‐up and timing of exposure were not reported |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Selection bias |
High risk |
All women admitted with ovarian cancer |
| Confounding |
Unclear risk |
Factors adjusted for age, education, parity, medical diagnosis of infertility, and length of attempt to first pregnancy |
| Performance bias |
High risk |
Self‐reported during an interview; unclear if interviewers were blinded to case‐control status |
| Detection bias |
Low risk |
Epithelial ovarian cancer by histological diagnosis |
| Attrition bias |
Unclear risk |
Unclear if exclusions were based on incomplete data |
| Selective reporting (reporting bias) |
Unclear risk |
Unclear if all fertility drugs investigated were reported |
