Table 3.

Prehospital triage according to RETTS-A compared with a reference patient

	All	Female	Male	≤ 65 yrs	>  65 yrs
n	4465	2319	2146	2034	2431
Sensitivity	0.806	0.782	0.830	0.867	0.774
	[0.778,0.834]a	[0.740,0.824]	[0.791,0.867]	[0.826,0.906]	[0.737,0.810]
Specificity	0.644	0.668	0.616	0.585	0.702
	[0.621,0.666]	[0.638,0.699]	[0.583,0.648]	[0.553,0.618]	[0.672,0.732]
PPV	0.486	0.477	0.495	0.379	0.586
	[0.459,0.515]	[0.439,0.516]	[0.457,0.534]	[0.342,0.418]	[0.548,0.622]
NPV	0.888	0.888	0.889	0.938	0.851
	[0.871,0.905]	[0.864,0.910]	[0.863,0.913]	[0.918,0.956]	[0.825,0.876]
LR +	2.26	2.36	2.16	2.09	2.60
	[2.11,2.43]	[2.13,2.63]	[1.96,2.38]	[1.91,2.30]	[2.32,2.90]
LR -	0.30	0.33	0.28	0.23	0.32
	[0.26,0.35]	[0.26,0.39]	[0.22,0.34]	[0.16,0.30]	[0.27,0.38]
AUROCb	0.725	0.725	0.723	0.726	0.738
	[0.707,0.745]	[0.699,0.751]	[0.698,0.748]	[0.701,0.752]	[0.714,0.762]
Accuracy	0.692	0.700	0.683	0.649	0.727
	[0.674,0.710]	[0.675,0.725]	[0.656,0.709]	[0.621,0.676]	[0.704,0.751]
Overtriage	0.356	0.332	0.384	0.415	0.298
	[0.334,0.378]	[0.304,0.362]	[0.351,0.417]	[0.383,0.446]	[0.269,0.329]
Undertriage	0.194	0.218	0.170	0.133	0.226
	[0.167,0.222]	[0.176,0.261]	[0.133,0.209]	[0.094,0.176]	[0.189,0.263]

PPV positive predictive value, NPV negative predictive value, LR Likelihood ratio, AUROC Area under the reciever operating characteristic curve

^a Bootstrapped 99% confidence intervals

^b Calculated on AUROC curve predefined sensitivity and specificity based on cutoffs in RETTS-A triage levels Red and Orange