Summary of findings 5. Large‐volume residual disease (LVRD) > 1 cm versus no macroscopic residual disease (NMRD) in IDS studies.

Large‐volume residual disease (LVRD) (> 1 cm) compared with NMRD after primary interval debulking surgery (IDS) in women with advanced epithelial ovarian cancer (EOC)
Population: women with advanced EOC after primary IDS Settings: all settings in adult women aged 18 years or older worldwide Prognostic factor: LVRD > 1 cm compared with NMRD
Outcomes	Relative effect (95% CI)	No of participants (studies)	Quality of the evidence (GRADE)	Comments
Overall survival: Median length of follow‐up: Not reported	Adjusted HR 2.23 (1.49 to 3.34)	343 participants (1 study reporting on 2 groups)	⊕⊝⊝⊝ very low123	We could not present illustrative absolute effects because a representative control group risk could not be ascertained from the studies. The HR estimates were adjusted for in multivariable analyses and this cannot be done in absolute terms, so we did not attempt it as the numbers were likely to mislead with any bias potentially favouring the NMRD threshold.
Progression‐free survival	Not reported
CI: confidence interval; HR: hazard ratio; EOC: epithelial ovarian cancer; IDS: interval debulking surgery; LVRD: large‐volume residual disease; NMRD: no macroscopic residual disease; OS: overall survival; PDS: upfront primary debulking surgery; PFS: progression‐free survival
GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate.

¹Downgraded by one level because we assessed the statistical analysis and reporting domain in the QUIPS tool as being at high or unclear risk of bias in all included studies. Either no conceptual framework was reported, where the variable selection criteria in multivariate model was unclear, or quite often the authors reported that significant variables from the univariate analysis were included in the multivariable model, but with no further details. This was the most serious bias from the QUIPS domains that could influence the effect estimates.

²Downgraded by one level for sparse data.

³Downgraded by one level for lack of generalisability and validity of results as reported in single analysis or very few included studies.