The randomised clinical trial (RCT) is the cornerstone in evaluating the beneficial and adverse effects of interventions (see The James Lind Library and Testing Treatments). Systematic reviews with meta-analyses of RCTs are acknowledged as essential tools in the evaluation of already implemented interventions, in considering new interventions to be implemented in clinical practice, or in the planning of further RCTs.

The Copenhagen Trial Unit (CTU) is a non-specialty oriented clinical intervention research unit. We offer flexible collaboration at all stages of clinical research as well as education in clinical trials. Trial methodology development is an indelible part of our services as it is recognised as an important tool for the quality of the clinical trial.

The core staff of the CTU consists of experienced trialists, clinicians, epidemiologists, statisticians, information-technology engineers, and information specialists.

The CTU is collaborating with the international Cochrane Collaboration in preparing, maintaining, and disseminating systematic reviews of the effects of health care. The Editorial Team Office of the Cochrane Hepato-Biliary Group (CHBG), part of the Cochrane Collaboration, is hosted within the CTU.

Furthermore, the CTU collaborates with academy and industry to constantly improve the methods of the RCT, herewith decreasing the risks of systematic errors (bias) and the risks of random errors (play of chance). In collaboration with universities and other research institutes, the CTU is running courses dealing with the various aspects of RCTs methodology and design, systematic reviews, meta-analyses, and trial sequential analyses.