ERCP-Related Adverse Events in Primary Sclerosing Cholangitis: A Systematic Review and Meta-Analysis

Table 5

Risk of bias of case-control study using the Newcastle-Ottawa scale.

	Selection				Comparability	Exposure
	Adequacy of case definition	Representativeness of cases	Selection of controls	Definition of controls	Comparability of cohorts on the basis of the design or analysis	Ascertainment of exposure	Same method of ascertainment	Nonresponse rate
Koskensalo (2020)	—		—		—			NR

NR, not relevant. Asterisks indicate the star rating according to the Newcastle-Ottawa scale for cohort studies. A study can be awarded a maximum of 4 stars for selection, 2 stars for comparability, and 3 stars for the outcome.