Table 1. Number of protocols and outcome domains by condition, year published, and whether specified as primary outcome.
| Characteristic | Number (%) of protocols | Number (%) of outcomes |
| All | 571 (100) | 1452 (100) |
| Condition addressed | ||
| Glaucoma | 22 (38.6) | 51 (35.2) |
| Cataract | 16 (28.1) | 35 (24.1) |
| Age-related macular degeneration (AMD) | 15 (26.3) | 47 (32.4) |
| Diabetic retinopathy (DR) | 4 (7.0) | 12 (8.3) |
| Year of protocol publication | ||
| 2000 or earlier | 6 (10.5) | 13 (9.0) |
| 2001 to 2005 | 15 (26.3) | 37 (25.5) |
| 2006 to 2010 | 29 (50.9) | 76 (52.4) |
| 2011 or later | 7 (12.3) | 19 (13.1) |
| Type of outcomes domain specified | Not applicable | |
| Outcomes specified as primary | 48 (33.1) | |
| Outcomes specified as non-primary | 88 (60.7) | |
| Type of outcome unclear | 9 (6.2) |
1
54 protocols and 3 completed reviews; One protocol did not include any of the outcome domains selected for detailed data extraction.
2
139/145 of the outcomes were described in the 54 protocols.