Tseng 2018.

Study characteristics
Methods	Retrospective cohort study
Participants	978 women with stage IIIB to IV ovarian, fallopian tube or primary peritoneal carcinoma Median age was 61 years (range: 19 to 95 years) FIGO stage ‐ n (%): IIIB: 33 (3%) IIIC: 761 (78%) IV: 184 (19%) Histology ‐ n (%): Serous: 869 (89%) Other: 109 (11%) Estimated blood loss: 700 mL (range: 5 mL to 8000 mL) Median hospital length of stay was 8 days (range 1 to 22 days) USA
Residual disease details	Speciality of surgeon not reported All women underwent primary debulking surgery followed by intraperitoneal (IP) chemotherapy in (n = 949, 99%) Residual disease was classed as follows: NMRD (defined as complete gross resection (CGR) in study) ‐ 0 mm: 408 (42%) SVRD (1 to 10 mm): 378 (39%) LVRD (> 10 mm): 192 (20%)
Outcomes	Multivariable analysis of factors associated with PFS adjusted for PDS‐year group Residual disease: NMRD: (AHR: reference) SVRD: (AHR 1.393, 95% CI 1.174 to 1.654) LVRD: (AHR 1.921, 95% CI 1.547 to 2.386) Multivariable analysis of factors associated with OS adjusted for PDS‐year group Residual disease: NMRD: (AHR: reference) SVRD: (AHR 1.36, 95% CI 1.118 to 1.653) LVRD: (AHR 1.751, 95% CI 1.378 to 2.224) Median operative time was 280 minutes (range, 36 to 893 minutes) Median length of hospital stay (LOS) was 8 days (range: 1 to 22 days) 30‐day all‐cause mortality was 0.4% (4 deaths)
Risk of bias (QUIPS)	1. Study participation (a‐f): low risk Adequate number of participants and description of target population. Baseline characteristics, eligibility criteria, sampling frame and period/place study took place presented clearly. 2. Study attrition (a‐e): unclear risk Unclear if patients with incomplete follow‐up were excluded before arriving at the stated sample size. Insufficient information to permit judgement. 3. Prognostic factor measurement (a‐f): low risk Valid and reliable measurement of RD Outcome level assessment: Outcome: overall survival 4. Outcome measurement (a‐c): low risk Valid and reliable measurement of outcome 5. Adjustment for other prognostic factors (a‐g): low risk Multivariate models for OS adjusted for age, albumin, FIGO stage, ASA score, histology, BRCA, tumour index, and postoperative intraperitoneal chemotherapy 6. Statistical analysis and reporting (a‐d): high risk No conceptual framework; unclear of variable selection criteria for multivariate analysis Outcome: progression‐free survival 4. Outcome measurement (a‐c): low risk Valid and reliable measurement of outcome 5. Adjustment for other prognostic factors (a‐g): low risk Multivariate models for PFS adjusted for age, albumin, FIGO stage, ASA score, histology, BRCA, tumour index and postoperative intraperitoneal chemotherapy 6. Statistical analysis and reporting (a‐d): high risk No conceptual framework; unclear of variable selection criteria for multivariate analysis
Notes	Median follow‐up for the entire cohort was 77.7 months (range: 1.3 to 198 months)