An overview of systematic reviews summarising the accuracy of brief cognitive assessments for identifying dementia in primary care

Abstract

Background In the UK, there is a lack of agreement between leading organizations on which tests should be used for dementia identification in primary care. The accuracy of many of the commonly-used brief cognitive assessments for dementia is imperfect, and guidelines for diagnosis lack consistent direction for health care professionals, policy makers and the public. Objectives To conduct an overview of existing systematic reviews summarizing the accuracy of brief cognitive assessments for identifying dementia, particularly for use in primary care. Methods We searched EMBASE, MEDLINE, PsychInfo and the Cochrane Database of Systematic Reviews from inception to 2015. We assessed the quality of included reviews using the Assessment of Multiple Systematic Reviews (AMSTAR) measurement tool and the risk of bias in systematic reviews tool ROBIS. Results were presented narratively with detailed tables summarizing key data. Main results We identified 13 reviews which included a number of different brief cognitive assessments for identifying dementia in primary care at a range of different thresholds. Included reviews assessed the diagnostic accuracy of 56 different assessments. Based on diagnostic test accuracy findings, we summarize the existing systematic review evidence, comment on the quality of evidence and make recommendations for research and clinical practice. Authors’ conclusions This overview has shown that the breadth of diagnostic test accuracy evidence is mixed, and there is not one brief cognitive assessment that clearly emerges as superior to others in terms of test accuracy. A number of methodological challenges present themselves within this overview. The value of conducting an overview review of diagnostic test accuracy is still debated, and we discuss both our initial aims and how these match against our overview findings. We encountered a number of issues of quality and consistency across the evidence base, and within this presentation we will consider applicability of the evidence and how generalizable this may be to the primary care population of interest. Finally, we will discuss the different purposes of an overview of systematic reviews of diagnostic test accuracy, and reflect on what other research methods may be helpful to address these objectives.