Table 2.
Minimal clinically important improvement (MCII) for HOOS and EQ-5D. Values are cut-point (95% CI) or AUC f
| MCII |
|||||||||
|---|---|---|---|---|---|---|---|---|---|
| 75th percentile approach
a
|
Receiver operating characteristic (ROC) approach |
||||||||
| PRO | Mean change approach a | All patients | Lowest tertile b | Middle tertile b | Highest tertile b | 80% speci-ficity c | Maximal accuracy d | 45° tangent line e | AUC f |
| Estimated from the hip-specific anchor question: “Overall, how are the problems now in the hip on which you had surgery, compared to before your operation?” | |||||||||
| HOOS Pain | 24 | 33 | 49 | 31 | 23 | 28 | 33 | 33 | 0.91 |
| 95% CI | (20–28) | (29–43) | (34–55) | (25–40) | (17–30) | (18–33) | (29–40) | (33–39) | (0.87–0.94) |
| HOOS-PS | 23 | 35 | 43 | 36 | 25 | 23 | 35 | 34 | 0.89 |
| 95% CI | (19–28) | (25–40) | (32–54) | (25–45) | (20–32) | (15–35) | (27–50) | (31–37) | (0.85–0.94) |
| HOOS QoL | 17 | 25 | 31 | 25 | 11 | 19 | 38 | 27 | 0.93 |
| 95% CI | (12–22) | (19–30) | (25–45) | (19–28) | (6–19) | (13–31) | (32–39) | (28–39) | (0.91–0.96) |
| EQ-5D Index g | 0.14 | 0.27 | 0.40 | 0.10 | 0.01 | 0.33 | 0.16 | 0.18 | 0.77 |
| 95% CI | (0.10–0.18) | (0.13–0.40) | (0.40–0.48) | (0.07–0.11) | (0–0.05) | (0.13–0.33) | (0.12–0.23) | (0.14–0.24) | (0.70–0.84) |
| EQ-VAS g | 7 | 20 | 22 | 20 | 5 | 15 | 23 | 11 | 0.76 |
| 95% CI | (1–12) | (15–21) | (20–50) | (10–25) | (–13–15) | (10–20) | (3–28) | (12–16) | (0.70–0.82) |
| Estimated based on the change from preoperatively to postoperatively and the general-health anchor question: “In general, would you say your health is...” | |||||||||
| EQ-5D Index g | 0.31 | 0.40 | 0.67 | 0.34 | 0.23 | 0.41 | 0.18 | 0.27 | 0.58 |
| 95% CI | (0.29–0.34) | (0.35–0.45) | (0.67–0.68) | (0.34–0.34) | (0.22–0.23) | (0.37–0.44) | (0.07–0.34) | (0.28–0.29) | (0.55–0.62) |
| EQ-VAS | 23 | 35 | 51 | 30 | 15 | 35 | 12 | 18 | 0.60 |
| 95% CI | (21–25) | (32–40) | (50–55) | (27–30) | (14–15) | (30–40) | (7–14) | (16–20) | (0.57–0.63) |
aAll patients answering “a little better” to the hip–improvement anchor or all patients answering to the general–health anchor 1 category better postoperatively than preoperatively.
b Tertiles (lowest third, middle third, highest third) of preoperative PRO scores.
cCut–point corresponding to the 80% specificity rule; all patients answering “a little better” and “much better” to the hip–improvement anchor or all patients answering to the general–health anchor 1 category better postoperatively than preoperatively.
dCut–point corresponding to the smallest residual sum of sensitivity and specificity; all patients answering “a little better” to the hip–improvement anchor or all patients answering to the general–health anchor 1 category better postoperatively than preoperatively.
eCut–point corresponding to a 45–degree tangent line intersection, equivalent to the point at which the sensitivity and specificity are closest together; all patients answering “a little better” to the hip–improvement anchor or all patients answering to the general–health anchor 1 category better postoperatively than preoperatively.
f Area under the curve; all patients answering “a little better” and “much better” to the hip–improvement anchor, from the 80% specificity approach, or all patients answering to the general–health anchor 1 category better postoperatively than preoperatively, from the 80% specificity approach.
g Anchor–PRO correlation < 0.30.