Table 2. Primary and Secondary Imaging Outcomes.
| Presentation, outcome | Encounters, No. (%) | AOR (95% CI)a,b | AORR (95% CI)a,c | P value | ||||
|---|---|---|---|---|---|---|---|---|
| Preintervention | Postintervention | |||||||
| Intervention | Control | Intervention | Control | Intervention | Control | |||
| Low back pain | ||||||||
| Encounters, No. | 1355 | 1461 | 1234 | 1306 | NA | NA | NA | NA |
| Primary outcome: lumbar imaging completed within 90 d | 243 (17.9) | 294 (20.1) | 194 (15.7) | 226 (17.3) | 1.01 (0.77-1.32) | 1.00 (0.83-1.22) | 1.00 (0.72-1.40) | .99 |
| Secondary outcomes | ||||||||
| Lumbar imaging ordered during encounter | 342 (25.2) | 390 (26.7) | 262 (21.2) | 298 (22.8) | 0.93 (0.70-1.23) | 0.95 (0.76-1.18) | 0.98 (0.68-1.40) | .91 |
| Lumbar MRI or CT ordered | 156 (11.5) | 163 (11.2) | 119 (9.6) | 151 (11.6) | 0.94 (0.60-1.46) | 1.19 (0.90-1.56) | 0.79 (0.47-1.33) | .38 |
| Lumbar MRI or CT completed within 90 d | 109 (8.0) | 111 (7.6) | 76 (6.2) | 98 (7.5) | 0.79 (0.58-1.08) | 1.04 (0.78-1.39) | 0.76 (0.50-1.16) | .20 |
| Neck pain | ||||||||
| Encounters, No. | 1285 | 1289 | 1164 | 1180 | NA | NA | NA | NA |
| Secondary outcomes | ||||||||
| Cervical imaging ordered | 367 (28.6) | 419 (32.5) | 340 (29.2) | 357 (22.8) | 1.10 (0.85-1.43) | 0.99 (0.84-1.17) | 1.11 (0.81-1.51) | .66 |
| Cervical imaging completed within 90 d | 259 (20.2) | 315 (24.4) | 245 (21.0) | 259 (21.9) | 1.11 (0.85-1.44) | 0.96 (0.76-1.20) | 1.16 (0.83-1.63) | .87 |
| Cervical MRI or CT ordered | 114 (8.9) | 127 (9.9) | 131 (11.3) | 104 (8.8) | 1.33 (0.97-1.82) | 0.87 (0.67-1.14) | 1.52 (1.02-2.28) | .04 |
| Cervical MRI or CT completed within 90 d | 73 (5.7) | 84 (6.5) | 91 (7.8) | 63 (5.3) | 1.32 (0.95-1.83) | 0.76 (0.53-1.07) | 1.75 (1.09-2.81) | .02 |
| All adult primary care | ||||||||
| Encounters, No. | 116 327 | 123 770 | 86 045 | 98 954 | NA | NA | NA | NA |
| Secondary outcomes | ||||||||
| Any imaging ordered | 20 558 (17.7) | 21 276 (17.2) | 17 048 (19.8) | 17 798 (18.0) | 1.15 (1.08-1.22) | 1.11 (1.02-1.20) | 1.04 (0.94-1.15) | .42 |
| Any imaging completed within 90 d | 14 767 (12.7) | 16 345 (13.2) | 12 216 (14.2) | 13 444 (13.6) | 1.15 (1.08-1.22) | 1.07 (0.98-1.17) | 1.07 (0.97-1.19) | .19 |
Abbreviations: AOR, adjusted odds ratio; AORR, adjusted ratio of postintervention vs preintervention odds ratios; CT, computed tomography; MRI, magnetic resonance imaging; NA, not applicable.
a
Adjusted for study site, patient age, patient sex, in-person vs telephone or video visit, and physician baseline characteristics (age, sex, years in practice, and tolerance of uncertainty). Encounters were nested within 25 intervention and 28 control clinicians.
b
Postrandomization vs prerandomization.
c
Intervention vs control ratio of postrandomization vs prerandomization odds ratios.