Table 3 Comparison with other studies.
| Govindan et al3 | Robaei et al5 | Yu et al7 | This study | ||
|---|---|---|---|---|---|
| Greenberg et al4 | |||||
| Study design | Population, USA | Population, Australia | Clinic, Hong Kong | Clinic, Singapore | |
| Study population | Children ⩽19 yrs (n = 509 with strabismus) | Children aged 7 yrs (n = 1739, 48 with strabismus) | All ages (n = 2704) XT: all ages | Children ⩽16 yrs (n = 682) | Children ⩽7 yrs (n = 494) |
| ET: children ⩽19 yrs | |||||
| Exotropia (XT) | |||||
| Intermittent | 71%* | 93% | 69% | 92% | 93% |
| Constant | na | 7% | 32% | 4% | 3% |
| Secondary | 23%† | na | na | 4% | 4% |
| Esotropia (ET) | |||||
| Infantile | 8.1% | na | 2%‡ | 23% | 25% |
| 46.5% | 34% | 48%‡ | 53% | 53% | |
| Accommodative | −36.4% | −20% | 29% | ||
| Fully | –10.1% | 25%‡ | –33% | 24% | |
| Partially | 16.6% | na | |||
| Acquired | 17.9%† | na | na | 17% | 16% |
| Secondary | 6% | 5% | |||
| XT: ET ratio | 35:65 | 35:65§ | 71:29§ | 72:28 | 67:33 |
*Intermittent X(T) includes subjects with convergence insufficiency. †Includes combination of central nervous system and sensory disorders. ‡Estimated from graph (1999–2001). A further 20% had microesotropia. §After removal of microstrabismus, vertical and incomitant strabismus.