Table 1.
Descriptive statistics of time-varying and time constant covariates
| Time Varying Covariates | 1998 (n=13,139) |
2000 (n=14,999) |
2002 (n=13,185) |
2004 (n=12,139) |
2006 (n=11,212) |
|---|---|---|---|---|---|
| CES-D | 2.09 ± 2.18 | 1.98 ± 2.13 | 1.92 ± 2.15 | 1.86 ± 2.14 | 1.89 ± 2.15 |
| Time since baseline (in years) | 2.36 ± 0.48 | 3.78 ± 1.07 | 5.75 ± 1.06 | 7.70 ± 1.04 | 9.67 ± 1.03 |
| Marriedt-1 | 9,360 (71%) | 10,491 (70%) | 8,790 (67%) | 7,966 (66%) | 7,300 (65%) |
| Δ Marital statust-1,t | −0.02 ± 0.14 | −0.05 ± 0.27 | −0.03 ± 0.21 | −0.02 ± 0.20 | −0.03 ± 0.21 |
| Household incomet-1 | 59.38 ± 83.77 | 62.55 ± 90.61 | 63.39 ± 103.72 | 61.75 ± 90.34 | 73.35 ± 73.51 |
| Δ Household incomet-1,t | −0.32 ± 92.22 | −1.39 ± 88.60 | −3.56 ± 86.73 | 10.15 ± 107.12 | −4.33 ± 93.69 |
| Self-rated healtht-1 | 2.66 ± 1.13 | 2.80 ± 1.13 | 2.70 ± 1.09 | 2.75 ± 1.08 | 2.81 ± 1.08 |
| Δ Self-rated healtht-1,t | 0.25 ± 0.92 | −0.04 ± 0.90 | 0.11 ± 0.88 | 0.11 ± 0.86 | 0.07 ± 0.86 |
| Diseasest-1 | 1.55 ± 1.21 | 1.61 ± 1.24 | 1.69 ± 1.24 | 1.85 ± 1.27 | 1.99 ± 1.28 |
| Δ Diseasest-1,t | 0.20 ± 0.56 | 0.13 ± 0.58 | 0.22 ± 0.58 | 0.18 ± 0.58 | 0.18 ± 0.57 |
| Functional statust-1 | 0.36 ± 1.17 | 0.35 ± 1.20 | 0.35 ± 1.17 | 0.50 ± 1.29 | 0.53 ± 1.35 |
| Δ Functional statust-1,t | 0.12 ± 1.16 | 0.07 ± 1.08 | 0.26 ± 1.19 | 0.14 ± 1.11 | 0.08 ± 1.16 |
| Time Constant Covariates | Total (n=17,196) |
White (n=13,644) |
Black (n=2,340) |
Hispanic (n=1,212) |
P value |
|---|---|---|---|---|---|
| Died (between baseline and 2006) | 4,061 (24%) | 3,207 (24%) | 603 (26%) | 251 (21%) | .0028 |
| Ever attrited (between baseline and 2006) | 1,537 (9%) | 1,132 (8%) | 268 (11%) | 137 (11%) | <.0001 |
| Age (in 1995) | 63.97 ± 10.23 | 64.32 ± 10.06 | 62.80 ± 9.93 | 62.28 ± 9.44 | <.0001 |
| Female | 10,061 (59%) | 7,832 (57%) | 1,506 (64%) | 723 (60%) | <.0001 |
| Education | 12.08 ± 3.27 | 12.64 ± 2.75 | 10.81 ± 3.53 | 8.30 ± 4.62 | <.0001 |
| Baseline marital status | 12,205 (71%) | 10,143 (74%) | 1,217 (52%) | 845 (70%) | <.0001 |
| Baseline self-rated health | 2.67 ± 1.14 | 2.56 ± 1.11 | 3.06 ± 1.14 | 3.15 ± 1.17 | <.0001 |
| Baseline disease | 1.51 ± 1.22 | 1.47 ± 1.21 | 1.77 ± 1.24 | 1.40 ± 1.20 | <.0001 |
| Baseline functional status | 0.35 ± 1.16 | 0.29 ± 1.05 | 0.59 ± 1.51 | 0.56 ± 1.47 | <.0001 |
| Baseline CES-D | 1.71 ± 1.96 | 1.57 ± 1.84 | 2.15 ± 2.16 | 2.46 ± 2.44 | <.0001 |
Note: Statistics are reported as mean ± standard deviation or n (%). Time varying covariates are those associated with repeated observations within individuals. Data based on the 1995–2006 Health and Retirement Study (HRS).