Accuracy of telephone screening tools to identify dementia patients remotely: systematic review

The COVID19 pandemic highlighted the need for remote diagnosis of cognitive impairment and dementia. Telephone screening for dementia may facilitate prompt diagnosis and optimisation of care. However, it is not clear how accurate telephone screening tools are compared with face-to-face screening. We searched Cochrane, MEDLINE, Embase, Web of Science, PubMed and Scopus for all English language papers published between January 1975 and February 2021 which compared telephone screening for dementia/ mild cognitive impairment and an in-person reference standard, performed within six-weeks. We subsequently searched paper reference lists and contacted authors if data were missing. Three reviewers independently screened studies for inclusion, extracted data, and assessed study quality using an adapted version of the Joanna Briggs Institute's critical appraisal tool. Twenty-one studies including 944 participants were found. No one test appears more accurate, with similar validities as in-person testing. Cut-offs for screening differed between studies based on demographics and acceptability thresholds and meta-analysis was not appropriate. Overall the results suggest telephone screening is acceptably sensitive and specific however, given the limited data, this finding must be treated with some caution. It may not be suitable for those with hearing impairments and anxiety around technology. Few studies were carried out in general practice where most screening occurs and further research is recommended in such lower prevalence environments.