Summary of findings 3. Azelaic acid compared to clindamycin.
| Azelaic acid compared to clindamycin for acne | ||||||
| Patient or population: participants with acne Settings: multicentres, recruitment in Germany, Netherlands, Norway, and Greece (1 study); three clinics in Tehran (1 study) Intervention: topical azelaic acid Comparison: topical clindamycin | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No. of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Topical clindamycin | Topical azelaic acid | |||||
|
Participants' global self‐assessment of acne improvement Good or very good improvement (long term: treatment duration > 8 weeks) |
591 per 1000 | 668 per 1000 (544 to 816) | RR 1.13 (0.92 to 1.38) | 229 (1 study) | ⊕⊕⊝⊝ Lowa | ‐ |
|
Withdrawal for any reason (long term: treatment duration > 8 weeks) |
103 per 1000 | 134 per 1000 (49 to 367) | RR 1.30 (0.48 to 3.56) | 329 (2 studies) | ⊕⊕⊝⊝ Lowb | ‐ |
|
Total number of participants who experienced at least one minor adverse event (long term: treatment duration > 8 weeks) |
160 per 1000 | 240 per 1000 | RR 1.5 (0.67 to 3.35) | 100 (1 study) |
⊕⊕⊝⊝ Lowc | There was no difference in minor adverse events (such as scaling and dry skin) between azelaic acid 5% gel and clindamycin 2% gel. |
| Quality of life | ‐ | ‐ | ‐ | ‐ | ‐ | Not measured |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. 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; RR: risk 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. | ||||||
aDowngraded by two levels to low quality evidence. One level for risk of bias: only one study included with unclear risk of selection, performance, and other bias, and with high risk of attrition and reporting bias. One level for imprecision: wide CI and optimal sample size not met. bDowngraded by two levels to low quality evidence. One level for risk of bias: both studies had unclear risk of selection and performance bias, and one study had a high risk of attrition and reporting bias. One level for imprecision: wide CI and optimal sample size not met. cDowngraded by two levels to low quality evidence. One level for risk of bias: only one study included with unclear risk of selection, performance and detection bias. One level for imprecision: CI and optimal sample size not met. *We choose a mean baseline risk from the studies included in meta‐analysis, calculated as number of participants in the control groups with event divided by total number of participants in control groups (study population) as assumed risk.