Mannel 2011.

Study characteristics
Methods	RCT
Participants	542 women with early stage of epithelial ovarian cancer. stage ⅠA or B grade 3 or clear cell subtype, or any stage IC, or stage II disease. Mean age was 55.1 years old in maintenance chemotherapy group and 56 in observation group Mean follow‐up time was 6.7 years
Interventions	Weekly paclitaxel 40 mg/m² × 24 weeks versus observation
Outcomes	OS, PFS
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "treatment was randomly assigned through the GOG Statistical and Data Center prior to receiving any chemotherapy." Comment: Probably done
Allocation concealment (selection bias)	Low risk	Quote: "The treatment assignment was not revealed until after the patient was successfully registered onto the study" Comment: Probably done
Blinding (performance bias and detection bias) All outcomes	Low risk	No blinding, but the outcome and the outcome measurement are not likely to be influenced by lack of blinding.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "18 patients randomized to the additional 24 weeks of paclitaxel withdrew during the follow‐up,14 patients of the control group withdrew during the follow‐up." Comment: It is balanced between the two groups
Selective reporting (reporting bias)	Low risk	All expected outcomes were reported
Other bias	Low risk	The study appears to be free of other sources of bias