The control data used in the International Program on Chemical Safety collaborative study on the intralaboratory and interlaboratory reliability of neurobehavioral screening methods were examined. In 14 neurobehavioral experiments in eight laboratories, control rats received vehicle only. Statistical analyses were conducted to determine control variability within studies within each laboratory, within laboratory replicability across studies, within laboratory stability of control values over the experimental period, and between laboratory comparisons of variability, replicability, and stability. For activity measures, rearing and motor activity varied considerably within studies, whereas home cage posture varied minimally. However, the grand coefficients of variation (CV) within laboratories and the overall CV across laboratories generally did not exceed 15% for rearing and motor activity. The autonomic measures lacrimation, salivation, pupil response, and palpebral closure were generally listed as normal in control rats. There was considerable interlaboratory variation in urination and defecation. The reproducibility of the excitability measures handling reactivity and ease of removal varied between and within laboratories. The grand CV within laboratories ranged from 8 to 67% for handling reactivity and from 11 to 70% for ease of removal. Replicability within laboratories was better for the arousal measure, within grand CV not exceeding 12% in six laboratories. Variability within and across laboratories was low for the neuromuscular measures landing foot splay, forelimb grip strength, hindlimb grip strength, and gait and righting. For the sensorimotor measures, the grand CV within laboratories ranged from 5 to 64% for approach response, 8 to 73% for touch response, 9 to 74% for click response, and 12 to 66% for tail pinch response. Within laboratories, body weight varied slightly and body temperature varied only minimally. The authors conclude that the control data produced by the eight collaborating laboratories exhibited reasonable comparability.
NIOSH-Author; Laboratory-animals; Neuromotor-activity; Neuromotor-system; Neuromotor-function; Laboratory-testing; Laboratory-techniques; Neurological-reactions; Nervous-system; Autonomic-nervous-system; Physiological-measurements; Measurement-equipment; Statistical-analysis;
Author Keywords: Proteomic analysis; PSD-93; Excitotoxicity; Ischemic stroke