Table 4. Mean Contrast Sensitivity and Prevalence of Impairment Across Weighted Sample Characteristics.
| logCS (SD) | Prevalence of contrast sensitivity impairment, % (95% CI) | |||
|---|---|---|---|---|
| <1.55 logCS | P valuea | >1 SD below meanb | ||
| Overall | 1.69 (0.007) | 21.7 (19.5-23.9) | 10.0 (8.5-11.4) | |
| Age groups, y | <.001 | |||
| 71-74 | 1.75 (0.010) | 14.1 (10.2-18.1) | 3.7 (1.8-5.6) | |
| 75-79 | 1.70 (0.012) | 17.8 (14.3-21.3) | 8.1 (5.4-10.8) | |
| 80-84 | 1.67 (0.008) | 22.9 (19.6-26.2) | 11.1 (8.6-13.6) | |
| ≥85 | 1.55 (0.013) | 40.2 (35.6-44.8) | 22.6 (18.9-26.3) | |
| Sex (self-reported) | .39 | |||
| Male | 1.68 (0.009) | 21.2 (18.2-24.3) | 10.7 (8.4-12.9) | |
| Female | 1.69 (0.009) | 22.1 (19.0-25.2) | 9.4 (7.5-11.3) | |
| Race and ethnicityc | .04 | |||
| Black, non-Hispanic | 1.64 (0.013) | 28.1 (23.8-32.3) | 14.4 (11.8-17.0) | |
| Hispanic | 1.62 (0.027) | 31.3 (22.0-40.5) | 17.5 (9.6-25.3) | |
| White, non-Hispanic | 1.70 (0.006) | 20.0 (17.8-22.2) | 9.1 (7.6-10.5) | |
| Other non-Hispanic | 1.61 (0.039) | 30.1 (16.5-43.8) | 9.6 (0.0-19.4) | |
| Education | <.001 | |||
| Less than high school graduate | 1.58 (0.018) | 34.6 (29.1-40.1) | 20.0 (15.4-24.6) | |
| High school graduate | 1.67 (0.010) | 22.0 (18.2-25.7) | 11.2 (8.6-13.8) | |
| Some college, no degree | 1.71 (0.012) | 20.0 (16.1-24.0) | 7.9 (5.1-10.7) | |
| College graduate or more | 1.71 (0.009) | 18.7 (15.6-21.9) | 7.4 (5.6-9.2) | |
| Income, $d | <.001 | |||
| 0 to <21 000 | 1.58 (0.014) | 36.1 (32.1-40.1) | 19.1 (15.6-22.7) | |
| 21 000 to <40 000 | 1.66 (0.011) | 24.4 (19.8-29.0) | 10.2 (7.5-12.9) | |
| 40 000 to <75 000 | 1.73 (0.010) | 15.9 (12.7-19.1) | 7.0 (4.8-9.3) | |
| ≥75 000 | 1.73 (0.008) | 15.5 (12.3-18.7) | 6.4 (4.7-8.2) | |
Abbreviations: logCS, log contrast sensitivity; VI, vision impairment.
a
P values are based on second-order Rao-Scott χ2 tests.
b
Based on distribution of contrast sensitivity in the National Health and Aging Trends Study sample. The sample mean (SD) was 1.65 (0.27), and impairment was defined as logCS <1.37.
c
Race and ethnicity data are self-reported by respondents upon enrollment. Multiple categories are allowed, and respondents are asked to select a primary race in these cases. The other non-Hispanic category includes reported races and ethnicities that are not Black, Hispanic, or White.
d
Quartiles are based on the income distribution of the sample.