Table 5. Comparison for the validity of self-reported diabetes without or with HbA1c test (n = 708).

	FPG values ≥7.0 mmol/L or use of diabetes medication (n = 708)			FPG ≥7.0 mmol/L or HbA1c ≥6.5% or use of diabetes medication (n = 708)
	Yes	No	Total	Yes	No	Total
Self-reported diabetes
Yes	71	2	73	71	2	73
No	19	616	635	43	592	635
Total	90	618	708	114	594	708
Validation measurements
Sensitivity, % (95% CI)	78.9 (69.0–86.8)			62.3 (52.7–71.2)
Specificity, % (95% CI)	99.7 (98.8–100)			99.7 (98.8–100)
PPV, % (95% CI)	97.3 (90.5–99.7)			97.3 (90.5–99.7)
NPV, % (95% CI)	97.0 (95.4–98.2)			93.2 (91.0–95.1)
Kappa (95% CI)	0.85 (0.79–0.92)			0.72 (0.65–0.80)

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).