Table 1.
Baseline Program to Improve Mobility in Aging (PRIMA) Characteristics Stratified by Tertiles of Standard Deviational Ellipse (N = 142)
| Standard Deviational Ellipse, km2 | |||||
|---|---|---|---|---|---|
| Total | Tertile 1 | Tertile 2 | Tertile 3 | ||
| ≥ 0.00 & <0.88 | ≥ 0.88 & ≤ 3.85 | > 3.85 & ≤ 1185.37 | |||
| Characteristic | (N = 142) | (n = 48) | (n = 47) | (n = 47) | P-value* |
| PPFI, % | 2.8 ± 2.6 | 3.6 ± 3.1 | 2.6 ± 2.2 | 2.1 ± 2.0 | 0.02 |
| Age, years | 77.0 ± 6.5 | 77.6 ± 7.1 | 77.0 ± 6.1 | 76.5 ± 6.3 | 0.72 |
| Sex, Women | 96 (67.6) | 34 (70.8) | 31 (66) | 31 (66) | 0.84 |
| Race | 0.38 | ||||
| White | 121 (85.2) | 41 (85.4) | 38 (80.9) | 42 (89.4) | |
| Black or African American | 14 (9.9) | 5 (10.4) | 4 (8.5) | 5 (10.6) | |
| Hispanic | 2 (1.4) | 0 (0) | 2 (4.3) | 0 (0) | |
| Asian | 1 (0.7) | 0 (0) | 1 (2.1) | 0 (0) | |
| Educational Attainment | 0.85 | ||||
| Postgraduate | 71 (50) | 22 (45.8) | 25 (53.2) | 24 (51.1) | |
| College | 44 (31) | 17 (35.4) | 15 (31.9) | 12 (25.5) | |
| High School | 23 (16.2) | 7 (14.6) | 6 (12.8) | 10 (21.3) | |
| Other | 4 (2.8) | 2 (4.2) | 1 (2.1) | 1 (2.1) | |
| Usual Gait Speed, m/s ** | 1.09 ± 0.16 | 1.04 ± 0.18 | 1.09 ± 0.14 | 1.12 ± 0.16 | 0.06 |
| Global Positioning System (GPS) Measures | |||||
| Median hours outside home | 3.6 ± 2.2 | 2.0 ± 1.6 | 3.3 ± 1.3 | 5.4 ± 2.2 | <.001 |
| Overall percent time outside home | 18.8 ± 10.7 | 12.1 ± 6.9 | 17.2 ± 7.4 | 27.1 ± 11.4 | <.001 |
| Median maximum distance from home | 6.9 ± 12.0 | 2.4 ± 1.6 | 6.0 ± 3.0 | 12.5 ± 19.3 | <.001 |
| Overall maximum distance from home | 36.0 ± 97.7 | 33.4 ± 133.6 | 21.8 ± 36.2 | 52.8 ± 96.0 | 0.30 |
Time-weighted standard deviational ellipses (SDE) represent the participant’s activity space in square kilometers (higher area = greater community mobility).
*
P-value for continuous variables from the One-way ANOVA and Chi-Sq. goodness of fit test for categorical variables across standard deviational ellipse tertiles.
**
Usual gait speed was assessed on a 14-foot instrumented walkway system (Zeno Walkway, Protokinetics LLC, Havertown, PA).
Data are presented as mean ± SD for continuous variables and n (%) for categorical variables.