Table 3.
Linear Regression Model Results: KOOS Function a
| Variable | Estimate (95% CI) b | P |
|---|---|---|
| Age | –0.29 (–0.36 to –0.22) | <.001 |
| Sex, female (vs male) | –2.19 (–3.58 to –0.81) | .002 |
| Race | ||
| Black (vs White) | 0.29 (–2.28 to 2.85) | .826 |
| Other (vs White) | –1.69 (–5.13 to 1.76) | .337 |
| BMI | –0.4 (–0.52 to –0.28) | <.001 |
| Years of education | 0.4 (0.18 to 0.63) | .001 |
| Smoking status | ||
| Quit (vs never) | 0.29 (–1.87 to 2.45) | .792 |
| Current (vs never) | –7.11 (–9.72 to –4.5) | <.001 |
| Baseline VR-12 MCS | 0.28 (0.22 to 0.35) | <.001 |
| Insurance, Medicaid (vs commercial) | –2.86 (–5.89 to 0.18) | .065 |
| Tear location | ||
| Medial (vs no tear) | 0.44 (–1.47 to 2.35) | .652 |
| Lateral (vs no tear) | 1.01 (–0.75 to 2.78) | .262 |
| Both (vs no tear) | 1.28 (–0.92 to 3.48) | .255 |
| Race × insurance | ||
| Black × Medicaid | –0.48 (–5.22 to 4.27) | .844 |
| Other × Medicaid | 0.3 (–8.46 to 9.06) | .946 |
a Boldface P values indicate statistical significance (P < .05). BMI, body mass index; KOOS, Knee injury and Osteoarthritis Outcome Score; VR-12 MCS, Veterans RAND 12-Item Health Survey Mental Component Score.
b This value represents the estimated change in KOOS Function. As an example, the estimated change in KOOS Function per 1-year increase in patient age is –0.29 points. The estimated difference in KOOS Function among female versus male patients is –2.19 points.