Table 4. Subgroup analysis by education and body mass index in validation of self-reported type 2 diabetes in Shanghai (n = 4,322).

	High school and above			Middle school and below			BMI ≥28 kg/m2			BMI <28 kg/m2
	Yes	No	Total	Yes	No	Total	Yes	No	Total	Yes	No	Total
Self-reported diabetes
Yes	258	14	272	320	16	336	132	5	137	446	25	471
No	102	1,733	1,835	123	1,751	1,874	40	258	298	185	3,230	3,415
Total	360	1,747	2,107	443	1,767	2,210	172	263	435	631	3,255	3,886
Validation measurement
Sensitivity, % (95% CI)	71.7 (66.7–76.3)			72.2 (67.8–76.4)			76.7 (69.7–82.8)			70.7 (67.0–74.2)
Specificity, % (95% CI)	99.2 (98.7–99.6)			99.1 (98.5–99.5)			98.1 (95.6–99.4)			99.2 (98.9–99.5)
PPV, % (95% CI)	94.9 (91.5–97.2)			95.2 (92.4–97.3)			96.4 (91.7–98.8)			94.7 (92.3–96.5)
NPV, % (95% CI)	94.4 (93.3–95.5)			93.4 (92.2–94.5)			86.6 (82.2–90.2)			94.6 (93.8–95.3)
Kappa (95% CI)	0.78 (0.75–0.82)			0.78 (0.75–0.82)			0.78 (0.71–0.84)			0.78 (0.75–0.81)

BMI, body mass index; CI, confidence interval; FPG, fasting plasma glucose; NPV, negative predictive value; PPV, positive predictive value.

Data for sensitivity, specificity, PPV, and NPV are shown as percentages (95% confidence intervals).

Data for Kappa is shown as Kappa value (95% confidence interval).