Table 4. Analysis of the accuracy of the obtained ratios in determine Erlenmeyer flask deformity.

Ratio	Accuracy (95% CI)
2 cm:base (cut-point=0.70)	Sensitivity 88.9% (70.8%, 97.6%)
	Specificity 91.9% (78.1%, 98.3%)
	PPV 88.9% (70.8%, 97.6%)
	NPV 91.9% (78.1%, 98.3%)
	Correct 90.6% (80.7%, 96.5%)
4 cm:base (cut-point=0.58)	Sensitivity 95.6% (75.7%, 99.1%)
	Specificity 100.0% (90.5%, 100.0%)
	PPV 100.0% (86.3%, 100.0%)
	NPV 94.9% (82.7%, 99.4%)
	Correct 96.9% (89.2%, 99.6%)
6 cm:base (cut-point=0.54)	Sensitivity 88.9% (70.8%, 97.6%)
	Specificity 97.3% (85.8%, 99.9%)
	PPV 96.0% (79.6%, 99.9%)
	NPV 92.3% (79.1%, 98.4%)
	Correct 93.8% (84.8%, 98.3%)

NPV, negative predictive value; PPV, positive predictive value.