[Series of risk of bias assessment (5): Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I)].

This paper summaries the Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I), a tool for evaluating risk of bias about Non-randomized Studies-of Interventions (NRSI), and introduces the application of ROBINS-I in a published NRSI. According to the characteristics of NRSI, evaluation field and signaling question were designed in ROBINS-I to provide essential information about risk of bias for NRSI included in systematic reviews. ROBINS-I is the tool in assessment of risk of bias in observational studies and quasi-randomised studies. Although the tool has been used in practice to some extent, but it still needs further improvement. Attention should be paid to its update and progress.