Table 2.

Multivariable Models in Prediction of Incident Frequent Knee Pain and Internal Validation (Calibration and Discrimination) of the Risk Prediction Models

Selected PredictorsBasic ModelBackward Model
OR (95% CI)P ValueOR (95% CI)P Value
Age (years)1.07 (0.98–1.16).161.15 (1.03–1.28).02
BMI (kg/m2)1.09 (1.01–1.17).021.13 (1.04–1.23).004
Mild knee symptoms*1.74 (0.88–3.44).12
Knee problems while climbing stairs2.06 (1.03–4.12).04
Morning stiffness3.03 (1.17–7.81).02
Postmenopausal status0.57 (0.28–1.18).13
Physically demanding work§2.05 (0.72–5.83).18
AUC of the model0.63 (0.55–0.71)0.71 (0.63–0.78)
Calibration: Hosmer-Lemeshow P value.72.93
Variance explained (Nagelkerke), %4.621.0
  • AUC, area under the curve of the receiver operating characteristic; BMI, body mass index; CI, confidential interval; OR, odds ratio.

  • Bold indicates P < .05.

  • * Pain in or around the knee within the last 12 months.

  • Defined with the Knee Injury and Osteoarthritis Outcome Score (KOOS) on physical functioning.

  • Defined with the KOOS on stiffness.

  • § Doing heavy physical work “quite often” or “(almost) always”.