EXPRESS 2005.

Study characteristics
Methods	RCT, placebo‐controlled, double‐blind Date of study: not stated Location: 32 centres in Europe and Canada
Participants	Randomised: 378 participants (mean age 43 years, 268 male) Inclusion criteria Participants with moderate‐severe psoriasis (PASI ≥ 12, BSA ≥ 10), age ≥ 18 years Exclusion criteria Immunosuppression Had received biologics Had an active infection Had past history of malignant tumours Dropouts and withdrawals (week 24) 41/378 (10.8%) Discontinued study: infliximab (18), placebo (7) No description of the reasons of withdrawals
Interventions	Intervention A. Infliximab (n = 301), IV, 5 mg/kg weeks 0, 2, 6 and every 8 weeks, 10 weeks Control intervention B. Placebo (n = 77), IV, equivalent, weeks 0, 2, 6 and every 8 weeks, 10 weeks
Outcomes	Assessments at 10 weeks Primary outcomes of the trial PASI 75 Secondary outcomes of the trial PASI90/50 PGA NAPSI
Notes	Funding source (p 386): This study was funded by Centocor, and Schering‐Plough, Kenilworth, NJ, USA" Declarations of interest (p 386): "Consultancies: Dr Reich (Abbott, Biogen Idec, Centocor, Schring‐Plough, Essex, Serano, Wyeth), Dr Nestle (Biogen Idec, Centocor, Schring‐Plough, Genentech, Galderma)..."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote (p 1368): "An adaptative treatment allocation was used... The treatment assignment was stored electronically and the stored data were used to allocate future patients in such a way that the imbalance between treatment groups was kept to a minimum" “Randomization was conducted via Interactive Response Technology, which assigned a randomisation number that linked the subject to a treatment arm and specified unique medication pack number" Comment: probably done
Allocation concealment (selection bias)	Low risk	Quote (p 1368): "An adaptative treatment allocation was used... The treatment assignment was stored electronically and the stored data were used to allocate future patients in such a way that the imbalance between treatment groups was kept to a minimum" Comment: probably done
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote (p 1368): "The investigators, study site personnel, and patients remained blinded until the database lock at week 50... placebo group" Comment: probably done, placebo controlled trial
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote (p 1368): "The investigators, study site personnel, and patients remained blinded until the database lock at week 50... placebo group" Comment: probably done
Incomplete outcome data (attrition bias) All outcomes	Low risk	378 included / 378 analysed Quote (p 1368): "The primary endpoint ... as well as.. were analysed on an intention‐to‐treat basis... In patients who discontinued the study agent ... the patients were regarded as not achieving the endpoints for binary responses" Comment: probably done
Selective reporting (reporting bias)	Unclear risk	Comment: no protocol available. The prespecified outcomes mentioned in the Methods section appeared to have been reported