Research and clinical criteria for development of neurobehavioral test batteries

Because neuropsychological testing can detect subtle changes in central nervous system function resulting from occupational and environmental exposure to toxic chemicals, it has been widely used in behavioral neurotoxicologic investigations. However, work in this field often has ignored the distinction between clinical and research testing when applying these assessment techniques. Experimental studies generally compare groups of subjects on specific outcome measures, whereas clinical work usually is focused on diagnosis and treatment of individual patients. Therefore, the inclusion criteria applicable to the selection of neuropsychological test batteries are different in research and clinical settings. Issues germane to test selection in research settings include sensitivity to neurotoxins, psychometric standards, sensitivity to central nervous system dysfunction, overview of cognitive functions, sampling of cognitive processing, sampling of output modalities, and examination of theoretical constructs. The usual questions asked in the clinical setting can be addressed most efficiently when the following issues are considered in test selection: sensitivity to specific toxicant exposure, estimation of native ability patterns, differential diagnosis, developmental specificity of tests and exposure effects, and description of patterns of cognitive strengths and weaknesses.