Efficacy of interventions for amblyopia: a systematic review and network meta-analysis

BACKGROUND: Many treatments are currently available for amblyopic patients; although, the comparative efficacy of these therapies is unclear. We conducted a systematic review and network meta-analysis (NMA) to establish the relative efficacy of these treatments for amblyopia. METHODS: Electronic databases (MEDLINE, EMBASE, Cochrane Library) were systematically searched from inception to Sep. 2019. Only Randomized clinical trials comparing any two or three of the following treatments were included: refractive correction (spectacles alone), patching of 2 h per day (patch 2H), patch 6H, patch 12H, patch 2H + near activities (N), patch 2H + distant activities (D), atropine (Atr) daily, Atr weekly, Atr weekly + plano lens over the sound eye (Plano), optical penalization and binocular therapy. The reviewers independently extracted the data according to the PRISMA guidelines; assessed study quality by Cochrane risk-of-bias tool for randomized trials. The primary outcome measure was the change in best-corrected visual acuity (BCVA) expressed as log MAR lines. Direct comparisons and a Bayesian meta-analysis were performed to synthesize data. RESULTS: Twenty-three studies with 3279 patients were included. In the network meta-analysis, optical penalization was the least effective of all the treatments for the change of visual acuity, spectacles (mean difference [MD], 2.9 Log MAR lines; 95% credibility interval [CrI], 1.8–4.0), patch 2H (MD, 3.3; 95% CrI, 2.3–4.3), patch 6H (MD, 3.6; 95% CrI, 2.6–4.6), patch 12H (MD, 3.4; 95% CrI, 2.3–4.5), patch 2H + N (MD, 3.7; 95% CrI, 2.5–5.0), patch 2H + D (MD, 3.5; 95% CrI, 2.1–5.0), Atr daily (MD, 3.2; 95% CrI, 2.2–4.3), Atr weekly (MD, 3.2; 95% CrI, 2.2–4.3), Atr weekly + Plano (MD, 3.7; 95% CrI, 2.7–4.7), binocular therapy (MD, 3.1; 95% CrI, 2.0–4.2). The patch 6H and patch 2H + N were better than spectacles ([MD, 0.73; 95% Crl, 0.10–1.40]; [MD, 0.84; 95% CrI, 0.19–1.50]). CONCLUSIONS: The NMA indicated that the efficacy of the most of the examined treatment modalities for amblyopia were comparable, with no significant difference. Further high quality randomized controlled trials are required to determine their efficacy and acceptability. SYSTEMATIC REVIEW REGISTRATION: CRD42019119843.