[Statistical study of the SIRSCAN computerised camera]

Abstract

The antibiograms of 1162 bacterial strains, including references, have been performed within four centres. They have been read manually and by the SIRSCAN camera, which yields to 30936 couples of diameters values. A non-concordance, at a 3 mm level, was observed fot 11.14% of the diameters. The mean of difference is 0.82 mm and the standard deviation 3.34 mm. Round Petri dishes gave results less reliable than those obtained with square dishes. A deviation in function of the centres is obtained for wild-strains as for the references. For the whole population a S/R discordance (sensible/résistant confusion) is obtained for 1.76% of the diameters. This value drops to 0.93% for enterobacteriaceae, P. aeruginosa and S. aureus (968 strains).