Table 3.

Studies reporting patients with functional or psychiatric disorder misdiagnosed as MS

Study	Year data collected	Methodology	Total misdiagnosed	Proportion misdiagnosed with FND, functional disorder or psychiatric disorder
Hankey and Stewart-Wynne [30]	1981	Reviewed records of patients either diagnosed with or told they might have MS	69/387 (17%)	All categories: 35/69 (51%) Functional disorder (n = 16), anxiety/hyperventilation (n = 14), hysterical conversion (n = 3), depression (n = 2)
Rudick et al. [31]	1986	Case series of ten patients who were misdiagnosed with MS	10 (n/a)	“Hysteria”: 1/10 (10%)
Poser [32]	1997	Review of patients with MS diagnosis referred for second opinion	130/366 (36%)	All categories: 36/130 (28%) Chronic fatigue syndrome (n = 28), post-traumatic syndrome (n = 5), psychiatric disorders (n = 3)
Walzl et al. [34]	2002–2004	Prospective cohort study of new neurology outpatients including 209 with MS	9/209 (4%)	All categories: 3/9 (33%) Anxiety (n = 2), chronic fatigue syndrome (n = 1)
Solomon et al. [6]	2014–2015	Multicenter case series comprised of patients misdiagnosed with MS	110 (n/a)	All categories: 28/110 (25%) Fibromyalgia (n = 16), conversion or psychogenic disorder (n = 12)
De Seabra et al. [36]	2009–2016	Retrospective study reviewing patient records at an MS clinic between 2009 and 2016 by applying 2010 McDonald criteria	44/635 (7%)	All Categories: 2/44 (5%) Dissociative disorder (n = 1), fibromyalgia (n = 1)
Kaisey et al. [35]	2016–2017	Patients with a prior established diagnosis of MS were reviewed in clinic and evaluated for fulfilment of 2010 McDonald criteria	43/241 (18%)	Fibromyalgia: 2/43 (5%)