Joseph J. Ryan, David S. Kreiner, Jennifer S. Seeley and Anthony M. Paolo
Base rates of impairment on the Temporal Orientation Scale (TOS; Benton et al.,) were reported for normal elderly (n=210) and patients with either Alzheimer’s disease (AD; n=112) or Parkinson’s disease (PD; n=189). The study hypothesis was that disorientation would be more frequent in ADs than in controls and PDs. Base rates for controls, PDs, and ADs were 1.00%, 22.22%, and 78.60% when disorientation was defined as ≥3 errors and 1.00%, 18.52%, and 72.30% when impairment was suggested by ≥4 errors. Receiver operating characteristic (ROC) analyses indicated excellent discrimination between controls and AD (AUC=0.919, 95% CI=0.879-0.958) along with good Sn and excellent Sp. Conversely, discrimination between control and PD groups was poor (AUC=0.642, 95% CI=0.587- 0.697) with low Sn and excellent specificity.