An alternative to interference indexes in neuropsychological time-sharing research

Interference indexes are used as criterion measures in a significant proportion of time-sharing paradigms in order to control for the initial discrepancy between left- and right-handed tapping rates. Problems associated with these indexes include low reliability, low statistical power, and especially correlations with baseline tapping rates. An analysis of covariance procedure using raw-score concurrent tapping rates as criterion measures, and baseline tapping rates as covariates, can effectively address these problems as demonstrated through a reanalysis of data.