Fielding 1980.

Methods	Study design: parallel RCT Recruitment: participants were recruited at discharge from the CCU Allocation: not reported Blinding: not blinded Randomisation: not reported Follow‐up(s): 6 months Description: weekly group meetings with a psychologist with relaxation training
Participants	Baseline characteristics Intervention group "Heart Club" Number of participants randomised: 5 Working before CHD: 5 Age: < 60 years Sex (male %): 100 Control group Number of participants randomised: 5 Working before CHD: 5 Age: < 60 years Sex (male %): 100 Inclusion criteria MI patients (according to ECG and enzyme criteria (not further specified)) Male < 60 years of age Exclusion criteria Previous history of heart disease or any other major physical illness Psychiatric complaint in the 2 years prior to present hospitalisation Baseline imbalances: ‐ Physically demanding work (i.e. white vs. blue collar): unknown Severity of CHD: unknown
Interventions	Intervention "Heart Club" Person‐directed psychological intervention comprising: weekly meetings for 10 weeks 1st h: anxieties or problems related to MI discussed 30 min of relaxation training (home practice was encouraged) Duration of intervention: 10 weeks Providers: psychologist, a physician attended the group on one session to answer questions of a medical nature and to discuss the mechanisms of MI Control group These participants were placed on a waiting list and received no meetings
Outcomes	Proportion at work at 6 months–12 months (medium term): 6 months Mean length of illness (sick leave) in days Anxiety with the Catell Self‐Analysis Form; 9‐point rating scale Adverse events (reinfarctions)
Identification	Sponsorship source: no information Country: UK Setting: single setting, outpatient Possible conflicts of interest: none reported Ethics committee approval:
Notes	Personal communication: information regarding occupational status of the study participants provided by the study author
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	A randomisation method was not described. Quote: "Ten patients were assessed and randomly allocated to experimental or control groups."
Allocation concealment (selection bias)	Unclear risk	None described
Blinding of participants and personnel (performance bias) All outcomes	High risk	Due to the nature of the study, blinding of participants was not possible. Control participants were placed on a ‘waiting list’, which might have influenced their decisions of when to return to work
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	There is no mention of blinding and information regarding the assessment of working status and illness duration is insufficient to determine if these were prone to detection bias.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No dropouts reported; no percentage of 'number working' reported, unclear how many participants remained in each group
Selective reporting (reporting bias)	Unclear risk	Unable to determine, no study protocol was available
Other bias	Unclear risk	None identified