Summary of findings 8. Nicotinamide compared to clindamycin.
| Nicotinamide compared to clindamycin for acne | ||||||
| Patient or population: participants with acne Settings: multicentres in USA (1 study); a teaching clinic of dermatology in Iran (1 study); St‐Alzahra hospital, Isfahan University of Medical Sciences, Isfahan, Iran (1 study) Intervention: topical nicotinamide 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 nicotinamide | |||||
| Participants' global self‐assessment of acne improvement | ‐ | ‐ | ‐ | ‐ | ‐ | Not measured |
|
Withdrawal for any reason (medium term: treatment duration from 5 to 8 weeks) |
74 per 1000 | 83 per 1000 (36 to 193) | RR 1.12 (0.49 to 2.60) | 216 (3 studies) | ⊕⊕⊝⊝ Lowa | Two trials had no withdrawals. |
|
Total number of participants who experienced at least one minor adverse event (medium term: treatment duration from 5 to 8 weeks) |
185 per 1000 | 222 per 1000 (135 to 369) | RR 1.20 (0.73 to 1.99) | 216 (3 studies) | ⊕⊕⊝⊝ Lowb | Local application site reactions (e.g. itching, burning, crusting) were reported in two studies. In the third study, the authors reported no side effects during the treatment. |
| 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: three studies included and all with unclear risk of bias, two with unclear risk of performance bias, one with high risk of attrition 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: all three studies with unclear risk of selection and detection bias, two out of three studies with unclear risk of performance bias. One level for imprecision: wide 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.