Objectives. To study the utility of the Mini-Cog test for detection of patients with cognitive impairment (CI) in primary care (PC). Methods. We pooled data from two phase III studies conducted in Spain. Patients with complaints or suspicion of CI were consecutively recruited by PC physicians. The cognitive diagnosis was performed by an expert neurologist, after formal neuropsychological evaluation. The Mini-Cog score was calculated post hoc, and its diagnostic utility was evaluated and compared with the utility of the Mini-Mental State (MMS), the Clock Drawing Test (CDT), and the sum of the MMS and the CDT ( ) using the area under the receiver operating characteristic curve (AUC). The best cut points were obtained on the basis of diagnostic accuracy (DA) and kappa index. Results. A total sample of 307 subjects (176 CI) was analyzed. The Mini-Cog displayed an AUC (±SE) of , which was significantly inferior to the AUC of the CDT ( ), the MMS ( ), and the ( ). The best cut point of the Mini-Cog was 1/2 (sensitivity 0.60, specificity 0.90, DA 0.73, and kappa index ). Conclusions. The utility of the Mini-Cog for detection of CI in PC was very modest, clearly inferior to the MMS or the CDT. These results do not permit recommendation of the Mini-Cog in PC. 1. Introduction The aging of the population has come along with an increase in the incidence of cognitive impairment (CI) [1], a clinical syndrome that, in about one-third of the patients, precedes dementia [2]. An early detection of CI could produce benefits at different levels, including early dementia diagnosis, access to treatments, and delay or even reversion of cognitive deterioration [3–5]. Primary care (PC) presents optimal characteristics of accessibility and continuity of care, which are essential for early detection and management of CI [6]. In this vein, the focus of the PC physicians should be the detection of CI, rather than dementia. A separation of mild cognitive impairment (MCI) and dementia would not only be difficult or arbitrary in many instances but would also lead to missing opportunities for treatment and research [7]. The detection of CI requires a proactive attitude and the use of cognitive tests. In PC, cognitive tests need to be brief and easy to administer and interpret. In addition, these tests should have been specifically validated in the PC setting, with an adequate control of the potential influence of age, education, and other social variables [8]. Albeit not simple, rather long, and very influenced by education, the Mini-Mental State (MMS) [9] is still the most used
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