Frequency of a false positive diagnosis of epilepsy: A systematic review of observational studies

PURPOSE To determine the frequency of false positive diagnoses of epilepsy and to explore its imitators and consequences. METHOD A systematic review of all published observational studies (to November 2015) was conducted to determine the proportion of false positive diagnoses of epilepsy. We included studies of people of all ages receiving a diagnosis of epilepsy. All observational study designs were included with the exception of case-reports and case series with fewer than 3 participants. RESULTS Data were available from 27 studies (31 reports), reporting considerably varied frequencies of false positive diagnoses. The frequency of false positive diagnosis range from 2% to 71%. The data also suggest that syncope and psychogenic non-epileptic paroxysmal events were the commonest imitators of epilepsy. Misdiagnosis led to mismanagement with anti-epileptic drugs (AEDs) and affected legal driving status and employment. CONCLUSIONS False positive diagnosis of epilepsy is common, even though there is considerable heterogeneity across studies. All potential imitators should be considered and clinicians should be cautious introducing AEDs without a definite diagnosis given the risk of side effects, and the possible impact on legal driving status and employment.