Summary of findings 5. N‐acetylcysteine compared to placebo for adults with depression in bipolar disorder.

N‐acetylcysteine compared to placebo for adults with depression in bipolar disorder
Patient or population: adults (aged 18 years+) with depression in bipolar disorder Setting: any setting (outpatient, inpatient, or both) Intervention: N‐acetylcysteine Comparison: placebo
Outcomes	Anticipated absolute effects* (95% CI)		Relative effect (95% CI)	№ of participants (studies)	Certainty of the evidence (GRADE)	Comments
	Risk with placebo	Risk with N‐acetylcysteine
Efficacy: number of participants who respond to treatment ‐ at 3 months	559 per 1,000	509 per 1,000 (288 to 731)	OR 0.82 (0.32 to 2.14)	69 (2 studies)	⊕⊕⊝⊝ LOW1
Efficacy: number of participants who achieve remission ‐ not reported	‐	‐	‐	‐	‐
Depression rating scale score ‐ at 3 months	‐	MD 1.28 higher (0.24 higher to 2.31 higher)	‐	58 (2 studies)	⊕⊕⊝⊝ LOW1
Acceptability: total dropouts ‐ not reported	‐	‐	‐	‐	‐
Acceptability: dropouts due to adverse effects ‐ not reported	‐	‐	‐	‐	‐
*The risk in the intervention group (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.
GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate; the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate; the true effect is likely to be substantially different from the estimate of effect.

¹ Downgraded by two points because of the very small sample size and the wide confidence interval.