Identification of Persons With Incident Ocular Diseases Using Health Care Claims Databases

In our claims-data analysis of 4 common ocular conditions, a disease-free interval ≤1 year insufficiently distinguished newly diagnosed from pre-existing disease, resulting in grossly overestimated incidence rates. Using look-back periods of 3-5 years, depending on the specific diagnosis, yielded considerably more accurate estimates of disease incidence.