Part-time Versus Full-time Spectacles for Myopia Control (ParMA Study): A Randomized Clinical Trial

Abstract

IntroductionTo compare myopia progression in school-aged children of Caucasian origin wearing part-time vs. full-time full correction with single-vision spectacles. MethodsThis prospective, randomized controlled trial included 30 children with bilateral myopia, who received either full-time or part-time treatment with single-vision spectacle lenses. Myopia progression was assessed as the mean change in cycloplegic spherical equivalent refraction (SE), mean change in axial length (AL), and mean change in sub-foveal choroidal thickness (SChT), over a 12-month follow-up period. ResultsA total of 32 eyes were treated with part-time single-vision spectacles (intervention group) and 28 eyes with full-time single-vision spectacles (control group), respectively. The part-time treated group reported no spectacle use during near-work activities for a mean of 6.2 hours/day. At the 12-month assessment, there was no significant difference between part-time and full-time correction groups in mean SE change (MD: -0.05 D, 95%

IMI 2023 Digest

“…While previously, most studies followed their cohort for 2 years, with an additional year in some studies to examine for any rebound, study results are being published earlier 74 , 102 , 106 , 111 , 114 , 120 , 125 and/or becoming more complex, sometimes involving longer durations with a “crossover” for the control group 103 or longer tracking for faster-progressing myopia 109 ( Table 2 ). However, all studies still show a reduced effectiveness of treatments in the second year, demonstrating the need for more than 1 year of follow-up to adequately assess the long-term efficacy of the treatment.…”

“…The extrapolation of a 1-year treatment effect to multiple years (an approach taken by many myopia calculators, for example) can lead to incorrect conclusions, 124 and hence the prior IMI recommendation for a clinical trial assessing the efficacy of a treatment for myopia control of a 3-year minimum study duration (at least 2 years of treatment plus an additional year of no treatment to examine any rebound effect) is still upheld. More recent studies have not applied randomization, 109 , 119 while others that randomize participants have not appropriately applied masking, 102 , 105 , 107 , 113 and stratification of participants has also become more common. 99 , 104 , 105 , 112 , 116 , 118 , 120 Several recent studies did not have a control group 109 , 111 while others used historical controls.…”

“… 1 These reviews provided informed recommendations on the design of future clinical trials to demonstrate the effectiveness of treatments at slowing myopia progression and the impact of these treatments on patients. Relevant publications since then up until September 2022 include 5 studies on spectacle interventions 98 – 101 (1 on part-time single vision wear), 102 4 soft contact lens (SCL) trials, 103 – 106 1 orthokeratology (ortho-k) study, 107 10 studies examining the effect of prescribing atropine (although only half assessed efficacy in a prospective trial), 108 – 117 and trials of atropine combined with either ortho-k 118 or SCL 119 or auricular acupoint stimulation. 120 The number of prospective clinical trials on myopia control has risen substantially.…”

“…The evidence since the original IMI white paper 141 and the IMI yearly digest 2021 1 was reviewed, and this update is largely limited to results from recent prospective, randomized clinical or group-matched trials, with a focus on SE refractive error and/or AL data as key outcome measures of efficacy and rebound effects on treatment discontinuation. Not comprehensively reviewed are data covering aspects such as visual performance and safety; data from studies that do not conform with standard clinical trial designs (e.g., see various studies 102 , 142 – 146 ) were also not comprehensively reviewed.…”

Myths in Myopia Epidemiology and Treatment

“…7 Similarly, there is limited evidence to support use of part-time wear of spectacles. 8 Thus, full correction of myopia remains the preferred practice for vision-related quality of life.…”