Random allocation IIBMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b4924 (Published 26 November 2009) Cite this as: BMJ 2009;339:b4924
- Philip Sedgwick, senior lecturer in medical statistics
- 1Centre for Medical and Healthcare Education, St George’s, University of London, Tooting, London SW17 0RE
A randomised, single blind, controlled trial investigated whether knee tape reduced pain and disability for patients with osteoarthritis of the knee.1 The trial had three intervention arms: therapeutic tape, control tape, and no tape. A total of 87 patients were recruited from an outpatient clinic. Allocation to an intervention was undertaken using groups of three consecutive patients. Within each group of three patients, each individual received a different intervention and the order in which the interventions were allocated was random.
Which one of the following statements best describes the method by which patients were allocated to an intervention?
a) Simple random allocation
b) Block random allocation
c) Systematic allocation
d) Cluster random …