Knee OA · Stepwise Nomogram

Clinical Improvement Probability

Enter the 6 patient predictors below. The calculator applies the Stepwise logistic regression nomogram to estimate the probability of clinical improvement after knee OA treatment.

Patient Predictors — Stepwise Model
Range: 40 – 90 years
5
0 No pain10 Worst pain
Timed Up & Go test
50
0 Extreme pain100 No pain
Result
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P(Improved) — Probability of Clinical Improvement
↑ Low probability Moderate High probability ↑
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Points per Variable
 Total Points —
Calculation Breakdown
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Stepwise Model — Reference Table
Variable Input Range Points Range Notes
Age40–90 yrs0–50Higher age → more points
bil_kneeUnilateral / Bilateral0 / ~18Bilateral adds points
KL Grade0–40–30Higher grade → more points
NPRS0–100–50Higher pain → more points
TUG0–60 s0–30Slower test → more points
KOOS Pain0–1000–50Lower score → more points
About the nomogram: Each predictor is mapped to a 0–100 point scale. Total Points (0–300) are mapped to a Linear Predictor (−1.5 to 3), which feeds into the logistic model: P = 1 / (1 + e−LP). Scales and mappings are calibrated from the published nomogram figure.