Table 1.

Comparison of the results

	False +	False −	Sensitivity	Specificity	NPV PPV
Banch Clausen	0.03%	0.0087%	99.9%	Not available	Not available
A.T. Wikman	1.1%	2.4%	Not available	99%	Not available
Lyn S. Chitty	0.7%	0.8%	99.3%	Not available	Not available
Ranjit Akolekar	Not available	3.5%	98.2%	100%	100% 96.5%
Gefmann-Holtzman	Not available	Not available	98.6%	95.4%	Not available
Allan T. Bombard	Not available	Not available	97.2%	96.9%	98.6% 94%
E. Breuer	Not available	Not available	Not available	100%	99.6%
Plesinac S.	2%	1%	98.6%	92%	97% 95.6%