Two-month randomized non-inferiority trial (the margin of non-inferiority is 20%) comparing three groups: self-refraction with adjustable glasses, receiving adjustable glasses; subjective refraction by an expert refractionist after computer optometry and receiving custom standard glasses; subjective refraction by an expert refractionist after computer optometry and receiving ready-made glasses. The main outcome of this study is the rate of glasses wear on twice-weekly covert evaluation by head teachers. And the continuous teacher assessment of wearing study glasses will be calculated as the number of times wearing glasses/ Total number of separate observations.
Two-month randomized trial comparing three groups.