ABSTRACT
This chapter shows that data obtained from three different sources—neurological signs and symptoms, psychometric test scores, and neurophysiological measures—are transformed into variables suitable for further toxic dose-neural response analysis. In clinical neurotoxicology research empirical approaches to symptom questionnaire designs coexist with time-honored symptoms inventories. Descriptions of single cases or clusters of cases where no quantification is attempted are also present in contemporary neurotoxicology literature. Chronic nervous system symptoms were those that persisted on weekends and vacations. These included fatigability, sleep disturbances, irritability, lack of concentration, memory problems, instability of mood, decreased libido or potency, and diminished alcohol tolerance. In data analysis, “lumping” refers to a data-analytical strategy that consists of creating new variables out of groups of single variables. Lumping is necessary because there are sometimes several dozens of variables dealing with nervous system function alone. Similar statements can be made regarding newly defined integrative indices of nervous system function or additive scores of neurological signs and symptoms.
