Longitudinal change of refraction over at least 5 years in 15,000 patients.

Background: To report the natural, longitudinal history of shifts in refractive errors in different age groups in a large western European cohort over at least 5 years in the same patients.

Methods: The electronic database of a large regional clinic containing 225,000 patients was searched for records of patients with a follow-up of at least 5 years, excluding all patients who had received any surgical interventions in any eye. This search retrieved 15,799 patients aged 3 months to 79 years (median 37.