Table 2.
Age- and Gender-Standardized Prevalence Percent of Cataract by Type and Study Center
| Cataract Type | North India (n = 2799⁎) |
South India (n = 3072⁎) |
P | Both Centers (n = 5871⁎) |
|||
|---|---|---|---|---|---|---|---|
| Prevalence (n) | 95% CI | Prevalence (n) | 95% CI | Prevalence (n) | 95% CI | ||
| Pure nuclear‡ | 28.9 (809) | 27.2–30.5 | 24.4 (750) | 22.9–25.9 | 0.01 | 26.5 (1559) | 24.7–28.4 |
| Pure cortical§ | 2.3 (64) | 1.8–2.9 | 4.3 (134) | 3.6–5.0 | <0.001 | 3.4 (198) | 2.8–4.0 |
| Pure PSC∥ | 4.8 (96) | 4.0–5.5 | 3.5 (146) | 2.8–4.2 | <0.05 | 4.1 (242) | 3.5–4.8 |
| Any pure or mixed nuclear | 48.0 (1346) | 46.1–49.8 | 38.0 (1165) | 36.6–39.7 | <0.0001 | 42.8 (2511) | 40.2–45.3 |
| Any pure or mixed cortical | 7.6 (213) | 6.6–8.6 | 10.2 (314) | 9.1–11.3 | 0.004 | 9.0 (527) | 8.1–9.9 |
| Any pure or mixed PSC | 21.0 (589) | 19.5–22.5 | 17.4 (533) | 16.1–18.8 | 0.003 | 19.1 (1122) | 17.8–20.3 |
| Any unoperated cataract⁎⁎ | 57.8 (1620) | 56.0–59.6 | 52.9 (1621) | 51.1–54.6 | 0.01 | 55.2 (3241) | 53.2–57.2 |
| Any operated or unoperated cataract | 73.8 (2073) | 72.3–75.3 | 71.8 (2198) | 70.3–73.3 | 0.3 | 72.7 (4271) | 71.1–74.4 |
CI = confidence interval; PSC = posterior subcapsular cataract.
⁎
Based on all those who attended the hospital clinic examination and underwent clinical examination or lens photography or both.
‡
Nuclear cataract defined as Lens Opacity Classification System III (LOCS III) ≥ 4.
§
Cortical cataract defined as LOCS III ≥ 3.
∥
Posterior subcapsular cataract defined as LOCS III ≥ 2.
⁎⁎
Any unoperated cataract defined as any nuclear cataract or cortical cataract or PSC or with dense opacities.