Summary of data on sex differences in retinal thickness
Numbers from six references cited by Dr. Leonard Sax as having "found a statistically significant difference between males and females", along with one more (Funk et al. 2003) that didn't.
Thickness measurements are in μm.
[Linked from "Retinal sex and sexual rhetoric", Language Log, 5/20/2008]
| Ref. | Description | Males [N] Mean (s.d.) {range} | Females [N] Mean (s.d.) {range} | M/F ratio |
Effect size | Notes |
| Hee et al. 1998 | ? | ? | ? | No specific numbers given by sex: "Macular thickness ... was slightly larger in males compared to females" | ||
| Asrani et al. 1999 | Black | 233 (10) | 214 (14) | 1.09 | 1.56 | 12 males and 17 females,
16 white, 13 black; no counts given for e.g. black females N per cell must be 7 to 8 max; sd's are unexpectedly small. |
| Asrani et al. 1999 | White | 240 (18) | 231 (10) | 1.04 | 0.62 | 12 males and 17 females,
16 white, 13 black; no counts given for e.g. black females N per cell must be 7 to 8 max; sd's are unexpectedly small. |
| Massin et al. 2002 | (sent for via interlibrary loan) | |||||
| Funk et al. 2003 | Retinal thickness | [29] 248.7 ~(21.8) ~{191-310} |
[71]
249.2 ~(21.8) ~{191-310} |
0.998 | -0.02 | Standard deviations and ranges given only for pooled data, since sex differences were negligible. |
| Funk et al. 2003 | Retinal nerve fibre layer (RNFL) thickness | [29]
109.3 (~21.8) ~{42-157} |
[71] 109.7 (~21.8) ~{42-157} |
0.996 | -0.02 | Standard deviations and ranges given only for pooled data, since sex differences were negligible. |
| Wakitani et al. 2003 | Macular thickness A | [116] 171 (21) |
[87] 162 (20) |
1.06 | 0.44 | |
| Wakitani et al. 2003 | Macular thickness B | [116] 215 (18) |
[87] 208(16) |
1.03 | 0.41 | |
| Wakitani et al. 2003 | Macular thickness C | [116] 234 (15) |
[87] 228 (13) |
1.03 | 0.43 | |
| Wong et al. 2005 | Central retina (1 mm dia.) thickness | [60] 203 (23) {163-259} |
[57] 189 (20) {138-226} |
1.07 | 0.65 | |
| Wong et al. 2005 | Foveal thickness | [60] 174 (21) {133-220} |
[57] 168 (23) {113-225} |
1.04 | 0.27 | |
| Huynh 2006 | Many measures | 789 boys, 754 girls 1009 White 245 East Asian | 1.03 (max) | 0.15 (fovea) 0.20 (central macula) | Large N; population study on children in Sydney Australia; see tables in main post for details.
(Standard deviations for effect-size calcuations determined from cited confidence intervals.) |
|
[N.B. description from Asrani et al. "Noninvasive mapping of the normal retinal thickness at the posterior pole", Ophthamology, 106(2) 269-273 1999: "Differences in median retinal thickness between genders were observed within the black subgroup (P = 0.03); differences between ethnic groups were observed within the female subgroup (P = 0.02). Although white males tended to have greater retinal thickness than did black males, this difference was small (9 μm) and insignificant. Similarly, white males tended to have greater retinal thickness than did white females; however, this difference was small (12 μm) and not statistically significant. The differences among gender and ethnic subgroups were due mostly to the subgroup of black females, who had the lowest values for retinal thickness (24 μm < black males; 21 μm < white females; 33 μm < white males)."]