To investigate the application of diagnostic criteria for functional movement disorders (FMD) which do not emphasize psychological etiology, compared with prior criteria, to facilitate retrospective chart review.

The current use of the term FMD, rather than psychogenic movement disorders (PMD), is partially based on recognition that some FMD cases do not have identifiable psychological factors. Existing FMD diagnostic criteria include psychological factors as part of core criteria, which may affect the ability to assess the prevalence of FMD independent of psychological factors or assess the influence of such factors on the time course of FMD.

We tested FMD criteria based on 2 core axes: examination findings and historical features and 1 independent, informational axis.  We identified FMD cases by manual chart review of outpatients with ICD10 code F44.4 in 2017. After excluding vocal cord predominant syndromes and non-motor functional disorders, we compared our FMD criteria with criteria published by Gupta and Lang (2009) and Shill and Gerber (2006).

Our cohort identified 29 patients with motor disorders coded with F44.4. Lang criteria identified 14 cases as established/definite, Shill criteria identified 6 cases as Clinically Probably/definite and 6 as Clinically Possible identified. Our criteria identified 14 cases as Clinically Probable/definite for a sensitivity and specificity of 100% compared to Lang criteria and 100% sensitivity and 89% specificity compared to Shill criteria.

Within this cohort, our FMD criteria yielded high sensitivity and slightly lower specificity compared to the Shill criteria which emphasized psychological factors. No cases identified by Lang or Shill criteria were missed by our criteria suggesting that FMD may be diagnosed without reliance upon psychologic features. Further work will be needed to test if psychologic criteria are better as supportive vs informational criteria for FMD. Larger cohort studies will be required to formally investigate.