Table 1
Comparison of selected prevalence studies on strabismus
| Study | Country | Study base | Total cases | Esotropes | Exotropes | Ratio eso/exo |
|---|---|---|---|---|---|---|
| *Oriental patients only. | ||||||
| Rantanen et al2 (1971) | Finland | Community (7 year olds) | 97 | 54 | 43 | 1.26 |
| Graham3 (1974) | UK | Community (5–6 year olds) | 210 | 173 | 37 | 4.68 |
| Kornder et al4 (1974) | Canada | Community (6 year olds) | 116 | 71 | 45 | 1.58 |
| Chew et al5 (1994) | USA | Community (7 year olds) | 1677 | 1187 | 490 | 2.42 |
| Friedman et al6 (1980) | Israel | Community (1–2½12 year olds) | 475 | 361 | 114 | 3.17 |
| Schlossman et al11 (1955) | USA | Institution (all age groups) | 1431 | 1107 | 324 | 3.42 |
| Mvogo et al9 (1996) | Cameroon | Institution (all age groups) | 137 | 51 | 86 | 0.59 |
| Ing et al10 (1974) | Hawaii | Institution (all age groups) | 202* | 66 | 136 | 0.49 |
| Yu et al (2001) | Hong Kong | Institution (age ≤7 years) | 1391 | 491 | 900 | 0.54 |
