Equivalence of two screens of cognitive functioning: The Short Portable Mental Status Questionnaire and the Orientation-Memory-Concentration test

OBJECTIVE: To determine the equivalence of two screens of cognitive functioning: the Short Portable Mental Status Questionnaire (SPMSQ) and the Orientation-Memory-Concentration (OMC) test. DESIGN: The design was cross-sectional and longitudinal. SETTING: Four rural and one urban county in the Piedmont region of North Carolina (n = 3210). PARTICIPANTS: A stratified random cluster sample (n = 3210) of people 68 years of age and older. MEASUREMENTS: SPMSQ and OMC at the fourth wave of the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE); disability, depression, and death measurements from the fourth through seventh waves of EPESE; demographic characteristics. RESULTS: On the SPMSQ and the OMC (r = .80), 15.3% and 38.4%, respectively, of those tested were rated cognitively impaired. Poorer scores were associated with older age, black race, and less education. These associations were attenuated on the dichotomized SPMSQ but not on the OMC. Both measures predicted disability and depressive symptomatology currently and 3 years hence and death. CONCLUSIONS: The SPMSQ and OMC, although highly correlated, are not equivalent. Association with race and education are greater for the OMC, whereas an association with age exists for both measures. The milder level of impairment identified by the OMC increases predictive capacity.