| Methods |
Retrospective cohort, Ausralia, 1978 to 1992, 1 centre |
| Participants |
Women treated or referred for IVF with known age and time of entry to cohort, N = 10,358, median age 32 (range 18 to 49), median age at the end of the follow‐up 38 (range 21 to 57) in exposed (N = 5564).Median age 31 (range 19 to 51), median age at the end of the follow‐up 38 (range 22 to 59) in unexposed (4794). |
| Interventions |
Infertility treatment, type of treatment CC/HCG/HMG, dosage NR, 2052 women underwent 1 cycle, 1362 2 cycles, 1637 between 3 and 5 cycles and 191 more than 6 cycles. |
| Outcomes |
Ovarian cancer by histological diagnosis from the Victorian Cancer Registry |
| Notes |
Total person‐years contributed was 31,272 for the exposed group and 35,655 for the unexposed group. Median length of follow‐up for exposed 5.2 (range 1 to 15.1), median length follow‐up for unexposed 7.6 (range 1 to 15.5) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Selection bias |
Low risk |
No person had ovarian cancer at the start of the study and at least with one ovary |
| Confounding |
High risk |
No adjusted analysis was reported and groups were not matched or balanced for confounding factors at baseline |
| Performance bias |
High risk |
Medical records, no blinding of assessors to exposure status reported |
| Detection bias |
High risk |
Cancer registry, no blinding of assessors to case status |
| Attrition bias |
Low risk |
67% for exposed group and 71% for the unexposed. |
| Selective reporting (reporting bias) |
Low risk |
All the infertility drugs used were reported. |
