Inter-rater reliability of the STEP protocol

An inter-rater reliability test of the Stepwise Comparative Status Analysis (STEP) is presented. The STEP is a protocol for the clinical examination o f patients with dementia, within the scope of a neuropsychiatric investigat ion. It combines psychiatric and neurologic bedside examination methods. Th e analysis is made in three steps where primary, observable symptom variabl es are successively aggregated via compound variables to the final determin ation of one of seven possible dominant regional brain syndromes (global, f rontal, subcortical, parietal, frontosubcortical, frontoparietal, other), h ere also called complex variables. In the present study, two senior physici ans assessed 50 patients independently and simultaneously. None of the pati ents was known to both physicians. In 42 patients (84%), the same dominant brain syndrome was determined by the two clinicians. The probability (P val ue) of this (or better) agreement was calculated at 2.0 x 10(-12). Kappa co efficients were calculated as a measure of assessment agreement regarding t he 50 STEP variables. For 20 variables, the coefficient was 0.75 or above, indicating excellent agreement; for 22 variables, the coefficient was below 0.75 and above 0.40, indicating moderate agreement; and for 4 variables, t he value was 0.40 or below, indicating poor agreement. Kappa calculations r egarding the assessments of four variables were either not possible or were considered inappropriate.