Table 2. Weighted distribution of 1989-2009 National Health Interview Survey participants aged ≥65 years at interview by availability of a Social Security Number (SSN) and corresponding % linked, adjusted hazard ratio (HR) and estimated % of links missed due to missing SSN.
| % distribution | % linked | Adjusteda HR for linking with the NDI (HR) | 95% CI | % of links missed among those without a SSN (1-HR) | 95% CI | % of links missed within race/ethnic group overall Pa(1-HR) | 95% CI | |
| All groups combined | ||||||||
| With SSN | 56.8 | 59.8 | 1.0 (Ref) | (unexposed) | ||||
| Missing SSN | 43.2 | 34.3 | .75 | .74, .76 | 24.8 | 23.6, 25.9 | 10.7 | 10.2, 11.2 |
| Hispanic | ||||||||
| With SSN | 47.4 | 48.9 | 1.0 (Ref) | (unexposed) | ||||
| Missing SSN | 52.6 | 23.5 | .66 | .61, .70 | 34.4 | 30.4, 38.7 | 18.1 | 15.9, 20.4 |
| Asian/Pacific Islander | ||||||||
| With SSN | 42.3 | 39.6 | 1.0 (Ref) | (unexposed) | ||||
| Missing SSN | 57.7 | 18.9 | .68 | .59, .78 | 32.0 | 21.9, 41.0 | 18.5 | 12.7, 23.9 |
| Black non-Hispanic | ||||||||
| With SSN | 55.1 | 60.3 | 1.0 (Ref) | (unexposed) | ||||
| Missing SSN | 44.9 | 35.7 | .70 | .67, .73 | 29.8 | 26.5, 33.0 | 13.4 | 11.9, 14.8 |
| White non-Hispanic | ||||||||
| With SSN | 57.9 | 60.7 | 1.0 (Ref) | (unexposed) | ||||
| Missing SSN | 42.1 | 35.5 | .77 | .75, .78 | 23.5 | 22.1, 24.8 | 9.9 | 9.3, 10.5 |
a. Adjusted for age group, sex, education level, respondent-rated health status, US nativity, and survey years. The model among all groups also adjusted for race/ethnicity.