On change scores and correlation

Abstract

Thorazine and Phenobarbital, the base line drugs used in the study, and Trilafon showed no significant change in tapping rates. With a single exception, these statements apply to all four types of tapping: forefinger, middle finger, simultaneous, and alternating. No differences were found among the first three kinds of tapping, but results based on these were different from those obtained with alternating pressings. The two behavior scales which were used in the study, the Lorr and Schedule B, detected significant emotional improvement during the medication period. No significant relations, however, were found between these scales and tapping speed although the data were in the direction of improved status and decrease in speedprobably due to the retarding effects of the new drugs. 6. SHAKOW, D. and HUSTON, P. . Studies of motor function in schizophrenia: I. Speed of tapping. 7. Veterans Administration: Cooperative studies of chemotherapy in psychiatry, Project No. 3, evaluation of phenyltoloxamine a new phrenotropic agent. Am.

The relationship between stroop interference and facilitation effects: Statistical artifacts, baselines, and a reassessment.

“…Unfortunately, the measurement of this relationship is complicated by a statistical dynamic that will produce spurious correlations whenever change scores are calculated from a common baseline (i.e., when calculated as ''(Y-Z/Z-X) where, in the present case, y = incongment means, X = congment means, and Z = neutral word baseline means; Fuguitt & Lieberson, 1974;Garside, 1962). This spurious covariation occurs because error variation in neutral word baselines produces a simultaneous or concurrent effect on facilitation and interference measures, increasing one at the direct expense to the other.…”