Gordon 2001.

Methods	Randomized, double‐blind, placebo‐controlled, multi‐center, 12 week induction trial Table of random numbers
Participants	30 adult patients with mild to moderate Crohn's disease (CDAI of > 151 and < 450) Oral corticosteroids (< 40 mg prednisolone or < 9 mg budesonide per day) permitted if dose was stable within 2 weeks of entry 5‐ASA, AZA or 6‐MP permitted provided treatment was not started within 2 months or the dose increased within 4 months of entry Female patents had to use contraception Exclusion criteria: pregnancy or breast feeding, weight > 100 kg, CDAI > 450 or inpatient due to Crohn's, patients treated with CYA, MTX or TAC, abdominal surgery within 3 months of entry or need for surgery, ileostomy or colostomy, laboratory‐confirmed intestinal infection, malignant neoplasm
Interventions	Patients received one infusion of natalizumab (3 mg/kg; n = 18) or placebo (n = 12)
Outcomes	The primary outcome was the change in mean CDAI at two weeks post‐infusion Secondary outcomes: remission (CDAI < 150), IBDQ, serum levels of CRP, ESR, blood count, peripheral blood T cells and B cells, serum natalizumab and anti‐natalizumab antibody concentrations Patients were evaluated at study entry and at weeks one, two, four, eight and twelve post‐infusion
Notes	Industry‐support: funded by Elan pharmaceuticals
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Table of random numbers
Allocation concealment (selection bias)	Low risk	Individual randomization concealment codes were held by the trial’s sponsor and each hospital’s pharmacy for emergency use, and none were opened during the study
Blinding (performance bias and detection bias) All outcomes	Low risk	Double‐blind: investigators and patients remained blinded to the randomization codes until data analysis was complete
Incomplete outcome data (attrition bias) All outcomes	Low risk	Patient withdrawals were described and distributed evenly across treatment groups
Selective reporting (reporting bias)	Low risk	All expected outcomes were reported
Other bias	Low risk	The study appears to be free of other sources of bias