Sensitivity of the Halstead Category Test Factor Scores to Brain Damage

Abstract

Recent factor-analytic studies of the Halstead Category Test (HCT) indicate that its seven subtests form three factors including a Counting factor (subtests I and II), a Spatial Positional Reasoning factor (subtests III, IV, and VII), and a Proportional Reasoning factor (subtests V, VI, and VII). The sensitivity and specificity of these factors to heterogeneous forms of brain damage was examined in a large sample of patients and a normal comparison sample. A prorated Impairment Index, which excluded the HCT error score, was used to assign participants with brain damage into mild, moderate, and severe impairment groups. Also, groups with various forms of neuropathology were contrasted. Results indicated that both the Spatial Positional Reasoning and the Proportional Reasoning factors were sensitive to brain damage. However, in all of the brain-damage groups, a greater percentage of errors were made on the Spatial Positional factor, suggesting that of the two it was more difficult for those with brain damage. The sensitivity and specificity of the Spatial Positional factor score for detection of brain damage was comparable to that of the total error score, which has been previously demonstrated to be an excellent indicator of brain damage. Findings provide further support for the validity of the HCT factors, and are consistent with the view that factor scores may be useful in interpreting the HCT.

ACKNOWLEDGEMENT

This material is based on work supported in part by the Office of Research and Development, Medical Research Service, Department of Veterans Affairs.

Notes

Age = Age in years, Education = Education in years, FSIQ = Wechsler Full Scale IQ score, CAT = Category Test total error score, II = Impairment Index, IIP = Impairment Index prorated on six test scores excluding the Category Test.

PC = Patient comparison group, BD = Brain-damage group; HCT = Halstead Category Test; CAT = HCT total percent errors, SPAT = HCT Spatial Positional Reasoning factor, PROP = HCT Proportional Reasoning factor. For Tukey post hoc analyses, P = PC group, M = Mild BD, D = Moderate BD, S = Severe BD.

Descriptive statistics for the Patient Comparison group are presented in Tables 1 and 2. Age = Age in years, Education = Education in years, FSIQ = Wechsler Full Scale IQ score, CAT = Category Test total percent errors, IIP = Prorated Impairment Index, SPAT = HCT Spatial Positional Reasoning factor percent errors, PROP = HCT Proportional Reasoning factor percent errors, ALC = Alcoholism group, TBI = Traumatic brain injury group. For Tukey post hoc analyses, P = PC group, T = TBI group, A = ALC group.

Sn = Sensitivity; Sp = Specificity; TP = True positives; TN = True negatives; FP = False positives; FN = False negatives. Specificity and sensitivity are reported as percentages, while TP, TN, FP, and FN are the number of individuals in the Patient comparison (n = 30) or brain-damaged groups (n = 202) who are correctly or incorrectly classified.