Stroop Test in the examination of psychiatric patients and patients with diabetes

Background:    Short-term memory, associated with short-time storage of the information necessary to perform a current task and of the information concerning the criteria for an action performed at a given moment, is referred to as the working memory. The Stroop Test is used for verbal working memory evaluation.
    Material/Methods:    The aim of this study is to evaluate the efficacy levels of the working memory and executive functions in healthy subjects (n=60), patients with paranoid schizophrenia (n=44), and patients with diabetes (n=62) – type 1 diabetes (n=31) and type 2 diabetes (n=31). The Stroop Test was used in the study.
    Results:    The best results were obtained by healthy subjects (RCNb/time: M=21.07, SD=0.42; RCNb/errors: M=0.02, SD=0.02; NCWd/time: M=51.83, SD=1.47; NCWd/errors: M=1.23, SD=0.23) and patients with diagnosed type 1 diabetes mellitus (RCNb/time: M=21.58, SD=0.70; RCNb/errors: M=0.16, SD=0.16; NCWd/time: M=52.68, SD=2.08; NCWd/errors: M=2.23, SD=0.54). The lowest scores were noted for the subjects with schizophrenia (RCNb/time: M=29.80, SD=1.78; RCNb/errors: M=0.12, SD=0.11; NCWd/time: M=90.39, SD=6.94; NCWd/errors: M=3.30, SD=1.12) and type 2 diabetes mellitus (RCNb/time: M=27.10, SD=1.92; RCNb/errors: M=0.32, SD=0.12; NCWd/time: M=65.23, SD=2.87; NCWd/errors: M=4.58, SD=0.74).). Sten (standard ten) norms of the Stroop Test were developed for the general population.
    Conclusions:    1. Healthy subjects and type 1 diabetics achieved significantly better results in Stroop Test performance than the studied schizophrenics and type 2 diabetics. 2. The standards, defined by the authors, provide normalization of results of patient performance on the Stroop Test and may be used in neuropsychological examination of subjects in the general population.

Keywords: Stroop, Diabetes, Schizophrenia, norms