Reported in the Review of Optometry, various methods utilized for slowing myopia progression were compared in efficacy and potential side effects. Looking at data from 23 randomized controlled trials, including 4,696 participants, pediatric eye doctors and study methodologists have found that anti-muscarinic eye drops provide the greatest effect on controlling the progression of myopia, but also are associated with some side effects.
The studies focused on and compared:
- Bifocal soft contact lenses
- Pharmaceutical eye drops such as anti-muscarinics
- Multifocal spectacles like PALs or Bifocals
- Both multifocal lenses and pharmaceutical eye drops.
Anti-muscarinic drops proved to be most successful but were associated with light sensitivity and/or blurred near vision.
Multifocal glasses mildly reduced the progression of myopia, while undercorrection actually seemed to increase the amount of myopia progression.
Here is a full link to the study. Students giving advice to patients on the progression of myopia should really consider referencing clinical trials like this one.