• neuromuscular disease
• systematic reviews

Doctors face an impossible task in appraising, synthesising, and regularly revisiting the evidence, even in a relatively small field such as neuromuscular disease. Randomised controlled trials are the most powerful tool for assessing and comparing the efficacy of different interventions.¹ With the possible exceptions of interventions with very large or very small effect sizes,^2,3 they provide the best research design to address questions of therapeutic efficacy. Properly designed randomised controlled trials minimise selection bias by ensuring the homogeneity of the comparison groups from the very start of the trial. Interventions for neuromuscular disease need testing in randomised trials as much as interventions in any other field. However, most neuromuscular diseases are uncommon so that collecting sufficient patients to answer even simple questions about interventions with moderate effects is difficult.