Background: A study-based database of clinical trials in eyes and vision would provide research evidence to clinicians, policymakers, researchers, and consumers. The first step in creating a study-based database is to assemble all available eye trial reports. Over the years, the Cochrane Eyes and Vision Group (CEVG) and its contributors have developed datasets of eye trial reports, which overlap to a certain degree, for various research projects. Objectives: Our initial objective was to integrate multiple datasets into a single comprehensive database of eye trial reports. Our long-term goal is to convert the report-based to a study-based register and to populate database fields with trial characteristics used in performing systematic reviews. Methods: Planning, including investigations of existing Cochrane study-based registers and development of a procedures manual, occurred over several months. We developed the ‘E-trials’ database by importing four overlapping datasets as comma-delimited files into a newly developed Microsoft (MS) Access database. The four datasets are: (1) a ProCite file containing the CEVG specialized register (CEVG-SR); (2) a MS Excel file containing a 10% random sample of the CEVG-SR trial reports indexed with International Classification of Diseases (ICD-10) and International Compendium of Health Indicators (ICHI) codes; (3) a MS Excel file of over 900 trial reports in eight ophthalmology journals; and (4) a ProCite file of all CEVG-SR reports indexed in MEDLINE. Results: Using detailed written procedures and multiple software programs, integration of the datasets proceeded well. Our database includes 11,925 trial reports of which 1785 (15%) are conference abstracts and 7525 (63.1%) are indexed in MEDLINE. The proportion of reports in our database that are MEDLINE-indexed has decreased over time, likely due to increasing numbers of conference abstracts included (see Figure). Most of the MEDLINE-indexed reports are tagged as publication type [pt] Randomized Clinical Trial (5749/7525 [76.4%]) or Controlled Clinical Trial [pt] (887/7525 [11.8%]). Conclusions: The first step of developing our study-based register is complete, and we were able to analyze information about trial reports.