Table 4.

Predictive Accuracy of Models of Multimorbidity for Psychological Distress

Additions to Baseline Model
CIRS Quintile Variables
Statistical MeasuresBaseline Model*No. of Chronic DiseasesCategoricalOrdinal
CIRS = Cumulative Illness Rating Scale; n/a = not applicable; ROC = receiver operating characteristic. * Including only the confounding variables (ie, sex, self-perceived social support, and self-perceived economic status).
Likelihood ratio test
    χχ2 (df)n/a2.53 (1)9.15 (3)9.13 (1)
    P value.112.027.003
Measures of explained variation0.09620.10040.12990.1298
    r2(y, p̂)0.11000.11970.14460.1445
    R2 analogue
Area under the ROC curve0.7470.7560.7760.777