Quality specifications for seminal parameters based on clinicians' opinions

The aim of this study was to identify analytical quality specifications for seminal parameters based on clinicians' opinions, and to compare with those based on biological variability and state of the art.

Two questionnaires with case histories were sent to laboratories participating in the Spanish programme of external quality on semen analysis for distribution to as many specialist clinicians as possible. Our intention was to determine the critical difference (CD), defined as the difference needed between two consecutive results obtained from semen analysis to be 95 % confident that the two results actually are different. Subsequently, we calculated the specifications of analytical quality in accordance with the clinicians' opinions.

The CDs obtained from the median value of the differences between the initial value and that given in the clinicians' replies were similar in clinical situations of improvement or worsening in the infertile normozoospermic male, and also in worsening situations for male patients presenting a significant alteration in seminal parameters. For improvement in this latter case, the CD cited as necessary in the clinicians' opinion was much higher than that for the other clinical situations. At a desirable level of quality, for concentration and total motility the coefficients of variation in the clinicians' opinion were below those based on biological variability and the state of the art. However, for type "a+b" motility, type "a" motility, morphology and vitality the coefficients of variation based on the clinicians' opinions were higher than those based on biological variability and lower than those based on the state of the art.

Quality specifications for seminal parameters based on clinicians' opinions depend to a large extent on the clinical situation and on the seminal parameter being analysed.