Friedman and Vedula (1273) searched several databases for studies on the effectiveness of lensextraction for chronic primary angle closure glaucoma compared with other interventions for the condition in people without past history of acute angle closure attacks. They found no randomized trials. The two non-randomized trials provided information on biological plausibility and treatment effect. However, they provided no proof because of methodological flaws. Conclusion:no proof so far, even though intuitively we like the concept. Comment: This is an important topic that badly needs a welldesigned prospective study.