Moene 2003.

Study characteristics
Methods	Study design: randomised controlled trial Study grouping: parallel group Adequate power (evidence of power calculation): No. Quote: "Another limitation is the lack of power of the study because of the small sample size". Allocation concealment method: participants were told they would receive same treatment, only at different starting points. Blinding of outcome assessors: 3 trained and independent raters blind to group membership and study rational rated the performance of motor tasks. Check of blinding: no information provided Duration of study: 1991–1996 Randomisation method: block randomisation
Participants	Baseline characteristics Intervention n: 24 Control n: 25 Overall n: 49 Duration of symptoms: 3.7 years Age (mean): 36.6 (SD 11.0) years Sex (% woman): 75% Marital status currently married (%): 75% Educational status: 20.5% had higher education Inclusion criteria: positive diagnosis of conversion disorder, motor type (such as paresis or paralysis, gait disturbances, co‐ordinations problems, aphonia, seizures, or pseudo‐epileptic seizures with motor activity) or a diagnosis of somatisation disorder with conversion symptoms, motor type according to DSM‐III‐R criteria; duration of symptoms ≥ 1 month; aged 18–65 years; no problem speaking the Dutch language; available for full course of treatment and assessment sessions; no other psychological treatment during the project; no imminent change in medication. Exclusion criteria: evidence of a neurological disorder explaining the conversion symptom;  major affective disorder or other severe psychiatric diagnosis requiring immediate treatment. Pretreatment: no significant differences between groups with respect to demographic variable, psychiatric history or dependent values at baseline. All Chi2 P values were > 0.15.
Interventions	Intervention characteristics Intervention Description: 10 weekly 1‐hour sessions, preceded by introductory session. Self‐hypnosis as homework between sessions. Length of treatment: 3 months Longest follow‐up after end of treatment: 6 months Comedications/other treatments while in the study: some participants received further hypnosis sessions if needed after end of treatment at 3 months. Control Description: wait list Length of treatment: 3 months Longest follow‐up after end of treatment: none Comedications/other treatments while in the study: none
Outcomes	Severity of impairment (VRMC) Outcome type: continuous Dropout Outcome type: dichotomous Data value: endpoint
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used for randomisation was not provided.
Allocation concealment (selection bias)	Unclear risk	All participants knew they would get the same treatment at different times. No evidence of this being a problem.
Blinding of participants and personnel (performance bias) All outcomes	High risk	All participants knew they would get the same treatment as informed of cross‐over study.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	2 trained and independent raters viewed the pretreatment video followed randomly by the posttreatment or follow‐up video.
Incomplete outcome data (attrition bias) All outcomes	High risk	Incomplete data as data were not reported for the 2 groups (control and intervention) separately. Dropouts accounted for. But no baseline characteristics reported.
Selective reporting (reporting bias)	Unclear risk	Results only reported for end of treatment, as follow‐up data were not comparable, as the control/wait list group had started treatment.
Other bias	Low risk	None described.