Association between the sonographer’s experience and diagnostic performance of IOTA simple rules

Table 4 Diagnostic performance of the five diagnoses

Diagnoses	Conclusive ratio (%)	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	+LR	−LR	Correct ratio (%)	Az	95% CI
Diagnosis 1	79.4	98.4	73.9	70.9	98.6	3.77	0.02	83.5%	0.85	0.797~0.900
Diagnosis 2	81.4	96.2	96.3	92.7	98.1	26	0.04	96.3	0.96*	0.923~0.983
Diagnosis 3	82.9	72.4	88.8	77.8	85.6	6.46	0.31	83.0	0.86^#	0.798~0.901
Diagnosis 4	92.0	100	94.0	90.5	100	16.7	0	96.2	0.97*^△	0.934~0.988
Diagnosis 5	81.4	96.7	87.3	81.7	97.8	7.61	0.04	90.7	0.92*^#△▲	0.870~0.952

Diagnosis 1 was made by a trainee of ultrasound according to the simple rules. Diagnoses 2 and 3 were made by an experienced and a less-experienced sonographer, respectively, according to their experiences. Diagnoses 4 and 5 were made by the experienced and less-experienced sonographer, respectively, according to their experiences, with diagnosis 1 as a reference
Az area under the ROC curve, CI confidence interval, PPV positive predictive ratio, NPV negative predictive ratio, +LR positive likelihood ratio, −LR negative likelihood ratio
*Compared with diagnosis 1, p < 0.01
^#Compared with diagnosis 2, p < 0.01
^△Compared with diagnosis 3, p < 0.01
^▲Compared with diagnosis 4, p < 0.01

ISSN: 1477-7819