A randomised trial of the effects of an additional communication strategy on recruitment into a large-scale, multi-centre trial.

Timely participant recruitment remains a significant challenge for most clinical trials. We evaluated the effects on participant recruitment of communication between the central trial coordinators and the clinical sites in the setting of a large international multi-centre clinical trial. The effects of communication were determined in a single-blind randomised controlled trial involving 167 clinical sites in 19 countries. Clinical sites were randomised to either additional or usual communication strategies - the additional communication group received a communication package based on additional, individually-tailored feedback about recruitment, in addition to the usual correspondence from the central trial coordinators that was provided to the control group. The two study outcomes were the median time to half randomisation target and the median total number of participants randomised per clinical site. Eighty-five clinical centres were randomised to receive additional communication and 82 to receive usual communication. At the conclusion of recruitment, there was no significant difference in the median number of participants randomised per centre between the additional and usual groups (37.5 vs. 37.0, p=0.68). The median time to half randomisation target was lower in the additional communication group compared to the usual group, however this difference did not achieve conventional levels of statistical significance (4.4 months vs. 5.8 months, p=0.08). The findings suggest that the additional communication strategy may be of some incremental benefit in helping sites achieve recruitment targets sooner.

Diabetes and vascular disease: a new international trial.

The prevalence of diabetes is increasing, particularly in developing regions of the world. The social and economic consequences of this disease and its complications are enormous. We discuss the scope and implications of the increasing burden of diabetes and describe the rationale and design of a new international study examining blood pressure lowering and glucose control interventions aimed at reducing the risk of vascular complications in people with type 2 diabetes. This study is the first large-scale randomized trial in diabetes to include participants from both lower- and higher-income regions of the world.