Logistic regression analysis. OR for the risk of developing CM (MM or in situ)
| OR | 95% CI | p Value | |
| Sex | |||
| Male | 1 | Ref | |
| Female | 0.72 | 0.6 to 0.8 | <0.001 |
| Age at index date (pterygium treated) | |||
| <50 years | 1 | Ref | |
| ≥50 years | 1.02 | 1.0 to 1.0 | <0.001 |
| Resident | |||
| Urban | 1 | Ref | |
| Rural/tropical | 1.05 | 0.9 to 1.1 | 0.31 |
| Pterygium | |||
| No | 1 | Ref | |
| Yes | 1.24 | 1.1 to 1.4 | <0.001 |