Table 6.

Incremental Predictive Value of Adding Insomnia (ISI) to Base Models.

Scale Model AUC (95% CI) ΔAUC (DeLong P) IDI % (P) NRI cat % (P) NRI cont % (P) Brier Score Calib Slope HL P Value
FINDRISC Base 0.781 (0.770–0.792) 0.162 0.97 0.42
FINDRISC Base +ISI 0.796 (0.786–0.807) +0.015 (P=0.002) +1.9 (P=0.004) +4.8 (P=0.03) +7.2 (P<0.001) 0.157 0.99 0.51
QDScore Base 0.794 (0.782–0.806) 0.154 0.95 0.37
QDScore Base +ISI 0.809 (0.798–0.820) +0.015 (P=0.001) +2.4 (P=0.002) +5.6 (P=0.02) +8.1 (P<0.001) 0.149 1.01 0.63
TRAQ-D Base 0.773 (0.760–0.786) 0.168 0.94 0.33
TRAQ-D Base +ISI 0.788 (0.776–0.800) +0.015 (P=0.003) +2.0 (P=0.005) +4.3 (P=0.04) +6.5 (P=0.002) 0.163 0.98 0.46

Base model: age, sex, social class, smoking, Mediterranean diet adherence, and physical activity. AUC: area under the receiver operating characteristic curve with 95% confidence intervals; ΔAUC tested with DeLong’s test. Calibration assessed by calibration slope (ideal=1.0) and Hosmer–Lemeshow (HL) goodness-of-fit P-value.

Calib, calibration; cat, categorical at pre-specified thresholds; cont, continuous; IDI, integrated discrimination improvement; ISI, Insomnia Severity Index; FINDRISC, Finnish Diabetes Risk Score; NRI, net reclassification improvement; QDScore, QResearch-derived diabetes risk score; TRAQ-D, Trinidad Risk Assessment Questionnaire for Type 2 Diabetes Mellitus.

RMMJ Rambam Maimonides Medical Journal Rambam Health Care Campus 2026; 17(3): e0019. ISSN: 2076-9172
Published online 2026 July 31. doi: 10.5041/RMMJ.10579