Table 3. Five-Year Health Care Use Associated With Study Group.
| Time | Health care service use, % | Group differences in annual change over the 5 y since study enrollmenta | Time-adjusted group differences across 5 y since study enrollmentb | |||
|---|---|---|---|---|---|---|
| LINKAGE | Usual care | Risk ratio (95% CI) | P value | Risk ratio (95% CI) | P value | |
| Primary care | ||||||
| Year 1 | 173/206 (84.0) | 192/221 (86.9) | 1.03 (1.003-1.067) | .03 | 0.99 (0.94-1.05) | .81 |
| Year 2 | 142/175 (81.1) | 153/182 (84.1) | ||||
| Year 3 | 121/164 (73.8) | 136/164 (82.9) | ||||
| Year 4 | 130/153 (85.0) | 118/145 (81.4) | ||||
| Year 5 | 125/152 (82.2) | 107/142 (75.4) | ||||
| Cumulative | 217/225 (96.4) | 222/230 (96.5) | ||||
| Any ED | ||||||
| Year 1 | 64/206 (31.1) | 78/221 (35.3) | 0.97 (0.89-1.07) | .57 | 0.92 (0.75-1.12) | .39 |
| Year 2 | 49/175 (28.0) | 57/182 (31.3) | ||||
| Year 3 | 44/164 (26.8) | 42/164 (25.6) | ||||
| Year 4 | 38/153 (24.8) | 46/145 (31.7) | ||||
| Year 5 | 40/152 (26.3) | 47/142 (33.1) | ||||
| Cumulative | 128/225 (56.9) | 139/230 (60.4) | ||||
| Any emergent type ED | ||||||
| Year 1 | 17/206 (8.3) | 16/221 (7.2) | 0.90 (0.73-1.12) | .34 | 1.02 (0.68-1.53) | .93 |
| Year 2 | 14/175 (8.0) | 17/182 (9.3) | ||||
| Year 3 | 8/164 (4.9) | 6/164 (3.7) | ||||
| Year 4 | 13/153 (8.5) | 12/144 (8.3) | ||||
| Year 5 | 11/152 (7.2) | 15/141 (10.6) | ||||
| Cumulative | 47/225 (20.9) | 47/230 (20.4) | ||||
| Any nonemergent type ED | ||||||
| Year 1 | 24/206 (11.7) | 31/221 (14.0) | 1.00 (0.84-1.19) | .98 | 0.79 (0.58-1.08) | .14 |
| Year 2 | 11/175 (6.3) | 22/182 (12.1) | ||||
| Year 3 | 19/164 (11.6) | 23/164 (14.0) | ||||
| Year 4 | 11/153 (7.2) | 23/144 (16.0) | ||||
| Year 5 | 16/152 (10.5) | 16/141 (11.3) | ||||
| Cumulative | 59/225 (26.2) | 77/230 (33.5) | ||||
| Any substance-related type ED | ||||||
| Year 1 | 19/206 (9.2) | 26/221 (11.8) | 0.79 (0.64-0.97) | .03 | 0.82 (0.51-1.32) | .41 |
| Year 2 | 16/175 (9.1) | 12/182 (6.6) | ||||
| Year 3 | 10/164 (6.1) | 16/164 (9.8) | ||||
| Year 4 | 2/153 (1.3) | 14/144 (9.7) | ||||
| Year 5 | 6/152 (3.9) | 9/141 (6.4) | ||||
| Cumulative | 35/225 (15.6) | 43/230 (18.7) | ||||
Abbreviation: ED, emergency department.
a
Group × linear time effect estimate; modified Poisson generalized estimating equations models included (linear) time, a time × group interaction term, and baseline age, Charlson Comorbidity Index, and emergent-type ED use.
b
Time-adjusted group effect estimate; modified Poisson generalized estimating equations models included (linear) time, no interaction term, and baseline age, Charlson Comorbidity Index, and emergent-type ED use.