5.1. Analysis.

Comparison 5 Fractional laser versus combined fractional laser plus any active intervention, Outcome 1 Within‐individual studies.

Within‐individual studies
Study	Interventions	Summary Outcomes	Comment
Faghihi 2015	One side: Fractional ablative CO₂ laser Other side: Fractional CO₂ laser plus punch elevation .	Serious adverse effects: All participants completed the allocated treatments and were included in the analyses. Investigator‐assessed scar improvement (short‐term: 4 months): 26/42 participants post‐fractional laser alone versus 31/42 participants post‐combined fractional laser and punch elevation reported > 50% improvement. Participant satisfaction: Participants were more satisfied with the combined fractional laser with punch elevation treatment than with the fractional laser alone. Participant‐reported adverse events (< 4 weeks): The most commonly reported adverse effect was transient erythema and crusting lasting for an average of 3 – 4 and 4 – 7 days, respectively. Investigator‐assessed adverse events (long‐term) (> 4 weeks): Mild post­inflammatory hyperpigmentation was observed in 21.4% of participants which lasted < 6 months.	Faghihi 2015 did not assess the primary outcome ‘Participant‐reported scar improvement’ and the secondary outcomes ‘Quality of life’ and ‘Post‐procedure down time’.
Lee 2011	One side: Fractional ablative CO₂ laser + intradermal injection with normal saline Other side: Fractional ablative CO₂ laser + intradermal treatment with autologous PRP.	Serious adverse effects: All participants completed the allocated treatments and were included in the analysis. Investigator‐assessed scar improvement (4 months): the mean overall degree of clinical improvement was 2.3 (SD 0.5) on the fractional laser alone side and 2.7 (SD 0.7) on the combined fractional laser plus PRP side (P = 0.03). Participant‐reported adverse events (< 4 weeks): All participants were observed to experience some degree of post‐treatment crusting. Oedema lasted an average of 7.1 (SD 1.5) days on the control side and 6.1 (SD 1.1) days on the experimental side (P = 0.04). Investigator‐assessed adverse events (3 months): erythema on the combined fractional laser + PRP side was significantly less and improved faster than on the fractional laser alone side. Post‐treatment oedema on the combined fractional laser + PRP side also improved faster than the fractional laser alone side.	Lee 2011 did not assess the primary outcomes ‘Participant‐reported failure of treatment’, ‘Participant‐reported scar improvement’ nor the secondary outcomes ‘Investigator‐reported failure of treatment’ ‘Participant satisfaction', ‘Quality of life’ and ‘Post‐procedure down time’.