Chen 2007.

Study characteristics
Methods	Aim of study: the acne treatment benefits of this oil‐free cleanser (SA microgel complex) were evaluated Design: double‐blind, randomised, vehicle controlled design Unit of allocation: patients Allocation: unclear Blinding: double‐blind Duration of trial (from recruitment to last follow‐up): not described Dropouts: not described
Participants	Population description: subjects of Fitzpatrick skin types I‐V Setting: not described Randomised number: unclear Age: 12 through 35 years Sex: either sex Severity of illness: mild to moderate acne
Interventions	Name of treatment group: SA group n = unclear Description: the cleanser containing the SA microgel complex Treatment period: unclear Timing: unclear Name of treatment group: vehicle group n = unclear Description: vehicle group (no detailed information provided) Treatment period: unclear Timing: unclear
Outcomes	Primary outcomes Participants' global self‐assessment of acne improvement (e.g. measured by a 4‐point scale: excellent, good, fair, and poor). "Global acne severity" was mentioned in the trial, but probably not this outcome Withdrawal for any reason. Authors did not report this outcome Secondary outcomes Change in lesion counts (total or inflamed and non‐inflamed separately). Time points not reported and no usable data. Physicians' global evaluation of acne improvement. "Global acne severity" was mentioned in the trial, but probably not this outcome. Minor adverse events (assessed as total number of participants who experienced at least one minor adverse event). No minor adverse events occurred, sample size unclear Quality of life. Authors did not report this outcome
Notes	Funding: supported by Neutrogena Corporation
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Although 'randomised' was mentioned, no details were reported for random sequence generation
Allocation concealment (selection bias)	Unclear risk	We judged an unclear risk of bias because the authors did not report this issue.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	This study was 'double‐blinded' and vehicle controlled, blinding probably sufficient
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	This study was 'double‐blinded' and vehicle controlled. Insufficient information about how blinding of outcome assessor was ensured
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	The authors did not report total number of randomised participants.
Selective reporting (reporting bias)	Unclear risk	Study published as abstract only
Other bias	Low risk	No other potential bias identified