Vision loss
| Article | Year | No. of eyes | >10/20 | 10/20–10/200 | CF | HM | LP | NLP |
| Copper and Ten9 | 1981 | 314 | 36.0% | 15.0% | 29.0% | 4.8% | ||
| De Faber et al11 | 2009 | 315 | 83.0% | – | – | – | – | 8.6% |
| Hatfield | 1969 | 377 | – | – | – | – | – | 10.6% |
| Knox et al16 | 2008 | 47 | – | – | 53% <6/60 | |||
| Kuhn et al17 | 2000 | 185 | 39.0% | 35.0% | 10.0% | 7.0% | 2.0% | 6.0% |
| Lee18 | 1966 | 262 | – | 14.8% | ||||
| Levitz et al19 | 1999 | 20 | 75.0% | 8.3% | – | – | 8.3% | 8.3% |
| Mansouri et al20 | 2007 | 437 | – | – | 7.6% | 1.1% | ||
| Singh et al24 | 2005 | 26 | 23.0% | – | – | 31.0% | ||
| Sundelin and Norrsell26 | 2000 | 52 | – | – | 11.5% | |||
| Vernon29 | 1988 | 57 | 93.0% | 7.0% | ||||
| N cases* | 521 | 114 | 159 | 100 | ||||
| Category† | 917 | 519 | 936 | 1648 | ||||
| Percentage‡ | 56.8% | 21.9% | 17.0% | 6.1% |