A Performance Standard for Clinical and Functional Observational Battery Examinations of Rats

Abstract

Clinical examinations are a key component of all toxicology studies and are a major component of the functional observational battery (FOB). The FOB is a core feature of the USEPA neurotoxicity screening guideline of 1991. The need for well-trained technicians is recognized, but technician competency is virtually always judged subjectively by their supervisors. Although subjective evaluation of performance cannot be replaced, what constitutes satisfactory performance is nebulous and therefore difficult to communicate to trainees and difficult to document. Consequently, a laboratory performance standard, with a clear pass-fail criterion, was developed to address this deficiency. The performance standard was an idealized composite of FOB data from experienced laboratory personnel, each person tested on a separate set of four groups of rats. The rats were examined in random order, and treatments were either (a) saline, (b) chlorpromazine, (c) atropine followed by physostigmine, or (d) amphetamine. Thus, the performance standard was the pattern of scores generated by the four treatments. After training, each technician was individually tested on four groups of rats similarly treated (random order, blind examination). The pattern of scores generated by the technician was compared to the performance standard by calculating a Pearson's cross-correlation coefficient. An r > 0.8 was considered passing. The use of the standard meets several laboratory goals: (a) good science (improved training leads to better studies), (b) documentation of observer competency required by the USEPA neurotoxicity guideline, (c) improved documentation of training for Good Laboratory Practices, and (d) objective documentation of performance for purposes of personnel management.