The scope of this study was to evaluate the accuracy, precision and specificity of the sperm concentration measurements by the Str?mberg-Mika Cell Motion Analyser (SM-CMA). Our data show that the instrument generally underscores the sperm concentration and therefore the uncorrected measurements must be corrected by the operator using the 'mouse'-driven option. In terms of precision, the system appears to have an excellent internal precision whereas its repeatability is influenced by the sperm concentration, the sample's homogeneity and the correction of the raw data. In order to increase the system's repeatability, we suggest that sperm counts should be carried out in various fields of the counting chamber, and the mean of the corrected values be taken as representative of the sperm concentration in the ejaculate if the various measurements show a homogeneous (poissonian) distribution. The correction of the raw data with the 'mouse'-driven correction option was also shown to improve the system's reproducibility. Concerning specificity, our data evidenced that, without technical correction, the instrument failed to correctly classify certain spermatozoa as such, thereby grossly underscoring sperm counts. This finding was more evident at low sperm counts. Overall, the SM-CMA requires additional laboratory time but the corrected sperm counts are comparable to manual counts and semi-automated counts with the added option that it provides the andrologists with various motility characteristics not possible with the latter methodologies.
Autoanalysis Computers