Alam 2014.

Methods	This pilot study was a single‐centre (at an urban academic institution), rater‐blinded, split‐face, placebo‐controlled, randomised clinical trial (from 30‐November‐2009 through 27‐July‐2010).
Participants	20 healthy adults (both genders) were enrolled (5 individuals dropped out, 15 completed the treatment and are analysed) Inclusion: "Age of 18 to 70 years, good general health, Global Acne Scarring Classification grades 2 through 4, and at least 2 5 × 5‐cm areas of acne scarring on the face (with at least 3 definable acne scars in each area)". Exclusion: "History of keloids or hypertrophic scars, skin infection or active skin disease other than mild acne in or around the study areas, active systemic or local skin disease likely to alter wound healing, treatment within the last 6 months or pending treatment within the subsequent 6 months with injectable fillers or ablative or non‐ablative laser resurfacing to the study areas, medication with isotretinoin or other oral retinoids within the past 12 months, current treatment with anticoagulants or antithrombotics, or allergy to topical anaesthetics".
Interventions	Intervention: 3 treatment visits were performed at 2‐week intervals (i.e. weeks 1, 3, and 5). At each of these visits, needling was performed on the study treatment area. Comparator: 3 treatment visits were performed at 2‐week intervals (i.e. weeks 1, 3, and 5). At each of these visits, topical anaesthetic was only massaged into the control area.
Outcomes	Improvement of acne scars (6 months), using the quantitative global scarring grading system, developed by Goodman 2006b then a scale of 1 to 4 (1 = < 25% improvement; 2 = 26% ‐ 50%; 3 = 51% ‐ 75%; 4 = > 75%) Participant satisfaction (6 months), using a word scale (very satisfied, satisfied, slightly satisfied, and unsatisfied) Any adverse event (6 months) Timing: at baseline, at 3 months and 6 months
Funding source	Departmental Research Funds, Department of Dermatology, Northwestern University, Chicago, Illinois
Declaration of interest	Dr Alam is employed at Northwestern University. Northwestern University has a clinical trials unit that receives grants from corporate and governmental entities to perform clinical research. Dr Alam has been a consultant for Amway and Leo Pharma, both unrelated to this research. Dr Alam has been principal investigator on studies funded in part by Allergan, Medicis, Bioform, and Ulthera. In all cases, grants and gifts in kind have been provided to Northwestern University and not Dr Alam directly, and Dr Alam has not received any salary support from these grants. Dr Alam receives royalties of less than USD 5000 per year from Elsevier for technical books he has edited.
Notes	USA Approved by the Northwestern University Institutional Review Board The trial was registered as ClinicalTrials.gov Identifier: NCT00974870 Written informed consent was obtained
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Randomly generated 1’s and 2’s were used to assign the leftmost labelled acne scar area on a given participant to the treatment arm (1) or the control arm (2), with the contralateral side then receiving the remaining assignment." Comment: Insufficient data
Allocation concealment (selection bias)	Low risk	Quote: "Randomly generated 1’s and 2’s were sealed separately in opaque envelopes." Comment: Probably done.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "Given that the control arm was easily distinguished from the treatment arm during treatment, participants and the treating dermatologist were not blinded." Comment: Probably not done.
Blinding of outcome assessment (detection bias) Investigator‐ assessed	Low risk	Quote: "The two dermatologist raters of photographs did not participate in randomisation or treatment and therefore were able to be blinded". Comment: Probably done.
Blinding of outcome assessment (detection bias) Participant‐reported	High risk	Quote: "Given that the control arm was easily distinguished from the treatment arm during treatment, participants and the treating dermatologist were not blinded." Comment: No blinding of participants and the outcome assessment is likely to be influenced by lack of blinding.
Incomplete outcome data (attrition bias) All outcomes	Low risk	20 individuals consented, and 5 dropped out before the first treatment. The remaining 15 completed all treatments and are analysed.
Selective reporting (reporting bias)	Low risk	The study protocol is available and all of the study’s prespecified outcomes that are of interest in the review have been reported in the prespecified way
Other bias	Low risk	The study appears to be free of other sources of bias