(Q36078844)
Statements
1 reference
Evaluation of the effects of an offer of a monetary incentive on the rate of questionnaire return during follow-up of a clinical trial: a randomised study within a trial (English)
1 reference
Peter Brocklehurst
1 reference
Pollyanna Hardy
1 reference
Jennifer L Bell
1 reference
Epidural and Position Trial Collaborative Group
1 reference
1 reference
Identifiers
1 reference