Researchers did this study to investigate the prevalence of MMD in the global population.

Researchers selected only those published literature of population-based studies on MMD prevalence with precise definitions to diagnose and classify MMD lesions by standardized grading methods. They used meta-analysis methods to calculate the pooled prevalence of MMD and its 95% CI in a random-effects model. The majority of MMD lesions would also be reported, together with the subgroup analysis of age, region, and gender. They also evaluated the correlation between MMD prevalence and spherical equivalent levels and axial length.

The present study included twelve studies with 58 558 subjects in this meta-analysis. The pooled prevalence of MMD in the world population was 2.1%. In the subgroup analysis, people with the following characteristics were at higher risk of developing MMD: female, urban life, living in Asia, older age, longer axial length, and severer myopia.

The study concluded that MMD is a severe public health concern worldwide, particularly in women, residents living in urban areas, subjects living in Asia, and longer axial lengths and severer myopia. Further studies from other continents/ethnicities are needed for comprehensive estimates of the prevalence of MMD globally.