Multi-centre trials randomisation

Having separate randomisation lists for the different centres in a multi-centre trial to ensure equal numbers of patients in the treatment groups within each centre is using centre as a stratification factor this will ensure that we do not end up with treatment being confounded with centre. 

Earlier we discussed the use of stratified randomisation in multi-centre trials and where the centres are large this is appropriate. With small centres however, for example in GP trials, this does not make sense and a stratified randomisation with region defining the strata may be more appropriate. Central randomisation would be essential to manage such a scheme. 

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MAVERIC) a multi-centre prospective randomised clinical trial on the secondary prevention of sudden cardiac death. Europace, 2004. 6(4) p. 257-66. 

This was a multi-centre, pan-European, randomised double-blind placebo-controlled clinical trial in acute stroke to evaluate the effect of ancrod, a natural defribrinogenating agent (Hennerici et al. (2006)). The primary endpoint was based on the Barthel Index a favourable score of 95 or 100 or a return to the pre-stroke level at three months was viewed as a success. The primary method of statistical analysis was based on a logistic model including terms for treatment, age category, baseline Scandinavian Stroke Scale and centre. 

A multi-centre study [43] carried out a randomised double-blind placebo controlled trial. Patients received a single infusion of 90 mg of pamidronate or placebo (saline) foot temperatures, symptoms and markers of bone turnover (bone-specific alkaline phosphates and deoxypyridinoline cross links) were measured over the 12 months, in ten visits. There results were extremely promising showing bisphosphonate, pamidronate, given as a single dose leads to a reduction in bone turnover. A recent RCT carried out in 2005 [44] concluded that alendronate taken orally 70 mg once weekly over a... 

Blaise S, Bosson JL, Diamand JM. Ultra-sound-guided sclerotherapy of the great saphenous vein with 1% vs. 3% polidocanol foam. A multi-centre, double-blind randomised trial with 3-year follow-up. Eur J Vase Endovasc Surg 2010 39(6) 779-86. 

Gillissen, A., Wittig, T.. Ehman, M., Krezdorn, H. G., de Mey, C. 2013. A multi-centre, randomised, double blind, placebo controlled clinical trial on the ef cacy and tolerability of GeloMyrtol forte in acute bronchitis. Arzneimittel-Forschung. 63(l) 19-27. 

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