Early orthoplastic soft-tissue coverage in open tibial fractures reduces infection, nonunion, and amputation

Table 2 Summary of risk-of-bias assessment for included studies

Ref.	Study design	Assessment tool	Key domains assessed	Total Newcastle-Ottawa Scale	Overall risk of bias
Khan et al[12], 2025	Retrospective cohort	Newcastle-Ottawa Scale	Clear inclusion criteria, objective outcomes, moderate control for confounders	6/9	Moderate
Henry et al[13], 2023	Retrospective cohort (single-arm)	Modified Newcastle-Ottawa Scale	Consecutive cases, long follow-up, no comparison group	5/9	Moderate
Sacks et al[14], 2023	Multisite retrospective cohort	ROBINS-I	Good selection, exposure well defined, moderate confounding between centers	Not applicable	Moderate
Zamorano et al[15], 2025	Retrospective cohort	Newcastle-Ottawa Scale	Well-defined population, objective outcomes, adequate follow-up	8/9	Low
Cochonat et al[16], 2025	Retrospective cohort	Newcastle-Ottawa Scale	Standardized data collection, clear timing groups, adequate follow-up	8/9	Low
Chua et al[17], 2014	Comparative retrospective study	ROBINS-I	Direct comparison (≤ 72 hours vs > 72 hours), consistent fixation, limited confounder control	Not applicable	Moderate
Sreedharan et al[18], 2024	Retrospective cohort from prospective database	Modified Newcastle-Ottawa Scale	Large cohort, objective outcomes, minor confounding not fully controlled	6/9	Moderate
Mahmoud et al[19], 2024	Retrospective cohort	Newcastle-Ottawa Scale	Well-defined exposure and outcomes, limited adjustment for covariates	6/9	Moderate
Cao et al[20], 2022	Large retrospective cohort	Newcastle-Ottawa Scale	Large sample, objective endpoints, well-documented follow-up	8/9	Low

ROBINS-I: Risk of Bias in Non-Randomized Studies of Interventions.