Table 3. Discriminatory capabilities of body silhouettes for identifying obesity (BMI≥30) retrospectively, according to sex and recall time in women and men age 30(±2) or 45(±2) years in ECRHS I or II with objectively measured height and weight and in RHINE II with self-reported height and weight.

Results of ROC curve analysis.

Reporting of body silhouette ECRHS III	Age	n	AUC (95% CI)	OC*	Youden Index	Sensitivity, % (95% CI)	Specificity, % (95% CI)	Correctly classified %
Women
Recall 9-15y	30±2y	172	0.92 (.87, .97)	5	.715	88.2 (.64, .99)	83.2 (.76, .89)	83.7
(ECRHS II)	45±2y	296	0.82 (.75, .89)	5	.511	72.7 (.54, .87)	78.3(.73, .83)	77.7
Recall 16-23y	30±2y	442	0.88 (.80, .96)	5	.633	75.0 (.48, .93)	88.3 (.85, .91)	87.8
(ECRHS I)	45±2y	305	0.80 (.72, .89)	4	.416	96.4 (.82, .99)	45.1 (.39, .51)	49.8
Men
Recall 9–15 y	30±2y	138	0.85 (.75, .95)	6	.533	66.7 (.41, .87)	86.7(.79, .92)	84.1
(ECRHS II)	45±2y	362	0.79 (.73, .85)	5	.433	85.2 (.73, .93)	59.1(.73, .83)	63.0
Recall 16–23 y	30±2y	365	0.78 (.63, .93)	5	.548	73.3 (.45, .92)	81.4(.45, .92)	81.1
(ECRHS I)	45±2y	362	0.80 (.72, .87)	5	.463	77.4 (.82, .99)	68.9 (.64, .74)	69.6
Reporting of body silhouette RHINE III	Age	n	AUC (95% CI)	OC*	Youden Index	Sensitivity, % (95% CI)	Specificity, % (95% CI)	Correctly classified %
Women
Recall 9-13y	30±2y	1145	0.92 (.88, .95)	5	.715	85.5 (.74, .93)	86.0 (.84, .88)	86.0
	45±2y	439	0.87 (.79, .94)	5	.679	85.7 (.70, .95)	82.2 (.78, .86)	82.5
Men
Recall 9-13y	30±2y	829	0.90 (.85, .96)	6	.689	77.3 (.62, .89)	91.6 (.89, .93)	90.8
	45±2y	997	0.84 (.80, .88)	6	.505	67.9 (.74, .93)	82.6 (.80, .85)	81.4

Abbreviations: AUC, Area Under the Curve; BMI, Body Mass Index; ECRHS, European community respiratory health survey; RHINE, Respiratory Health In Northern Europe.

*OC, optimal sensitivity and specificity criterion in relation to body silhouette.