Haldorsen 1998.

Methods	RCT; 2 arms; assessed pre‐treatment, 1 year
Participants	End of treatment n = 387 Start of treatment n = 469 Sex: 298 F, 171 M Mean age = 43 (SD 10.6) Source = National Insurance system contact Diagnosis = mixed chronic pain Mean years of pain = not given
Interventions	"Cognitive behaviour therapy" "Treatment as usual"
Outcomes	Primary pain outcome: VAS pain Primary disability outcome: none Primary mood outcome: HSCL distress Catastrophising outcome: none Visual analogue scale pain (in afternoon) Physical training Hopkins Checklist (HSCL) Distress (Norwegian version) Attribution style Work satisfaction Ergonomic performance Subjective health rating
Notes	CBT versus TAU post‐treatment: analyses 4.1, 4.3 Yates quality scale: total quality = 12/35, design quality = 10/26, treatment quality = 2/9
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Allocated at random by cards in sealed envelopes
Allocation concealment (selection bias)	Low risk	Allocation sequence by someone not involved in study
Incomplete outcome data (attrition bias) All outcomes	High risk	Attrition partially reported; no test for differences
Selective reporting (reporting bias)	High risk	Not fully reported
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Assessment by physiotherapists who tried to remain blind to treatment