Pilowsky 1990.

Study characteristics
Methods	Design: parallel Duration: 12 weeks Assessment: baseline and post‐intervention Country: Australia
Participants	Pain condition: chronic, intractable 'psychogenic' pain Population: patients with chronic, intractable ‘psychogenic’ pain Minimum pain intensity: no Inclusion criteria Complaint of pain for at least 1 month, which is not responding adequately to appropriate treatment Absence of objective evidence for the presence of any significant organic disease sufficient to explain the presence or severity of the pain experience and degree of disability Impairment of functioning by at least 25% taking into account biological, personal, social, occupational and recreational aspects Exclusion criteria Physical and mental health comorbidities Total participants randomised: 129 Age in years (mean): 42.26 Gender: 80/129 were female Pain duration in years (mean, SD): NR
Interventions	Amitriptyline + pyschotherapy n = 26 Combined intervention: TCA + psychotherapy Amitriptyline: flexibly dosed up to 150 mg/day Psychotherapy: 12 weekly, 45‐minute psychotherapy sessions focusing on "facing inner conflicts" that were theorised to be causing physical pain Amitriptyline + support n = 26 TCA Amitriptyline: flexibly dosed up to 150 mg/day Support to 'match' psychotherapy: 6 x 2‐weekly. 15‐minute sessions that focused on the physical symptoms, effects and side effects of medication Placebo + psychotherapy n = 26 Inert placebo Psychotherapy: 12 weekly, 45‐minute psychotherapy sessions focusing on "facing inner conflicts" that were theorised to be causing physical pain Placebo + support n = 24 Inert placebo Support to 'match' psychotherapy: 6 x 2‐weekly, 15‐minute sessions that focused on the physical symptoms, effects and side effects of medication
Outcomes	Pain intensity Withdrawal
Missing data methods	Completer analysis
Funding source	Non‐pharmaceutical: "We are indebted to the National Health and Medical Research Council who provided generous support for the conduct of this study."
Conflicts of interest	NR
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomised to 1 of 4 treatment groups with the use of a table of random numbers.
Allocation concealment (selection bias)	Unclear risk	Allocation procedure not specified
Blinding of participants and personnel (performance bias) All outcomes	High risk	No mention of blinding procedures between psychotherapy/support and amitriptyline/placebo.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Very different intervention experience for those undergoing psychotherapy versus simple support. Triallists attempt to control for effects of contact in therapy by having clincian support, but participants would be aware of their intervention
Incomplete outcome data (attrition bias) All outcomes	High risk	Completer analysis only. Original numbers of participants in arms not given, and withdrawal only given in percentages. No reasons given for withdrawal Attrition Total: 28/129 (21.7%) Amitriptyline ≤ 150 mg + psychotherapy: 6/26 (24%) Amitriptyline ≤ 150 mg + support: 7/26 (25%) Psychotherapy: 5/26 (19%) Support: 7/24 (31%)
Selective reporting (reporting bias)	High risk	Some outcome measures mentioned in the methods don't seem to be reported in the results section (e.g. McGill pain questionnaire). No protocol or trial registration found
Other bias	Low risk	No other sources of bias were identified.