Summary of findings 2. Azathioprine versus no intervention for primary biliary cholangitis.

Azathioprine versus no intervention for primary biliary cholangitis
Patient or population: people with primary biliary cholangitis Settings: secondary or tertiary care Intervention: azathioprine Comparison: no intervention
Outcomes	Illustrative comparative risks* (95% CI)		Relative effect (95% CI)	No of participants (trials)	Quality of the evidence (GRADE)
	Assumed risk	Corresponding risk
	No intervention	Azathioprine
Mortality at maximal follow‐up Follow‐up: 63 months in 1 trial and not stated in 1 trial	208 per 1000	128 per 1000 (78 to 205)	OR 0.56 (0.32 to 0.98)	224 (2 trials)	⊕⊝⊝⊝ Very low1,2
Serious adverse events (proportion)	None of the trials reported this outcome.
Serious adverse events (number of events)	None of the trials reported this outcome.
Health‐related quality of life	None of the trials reported this outcome.
*The basis for the assumed risk is the mean control group proportion across all the trials. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; OR: odds ratio.
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.

¹ Risk of bias in the trial(s) was high (downgraded by two levels).
 ² Sample sizes were small and 95% confidence intervals overlapped clinically significant and clinically insignificant or no effect (downgraded by two levels).