There are clear research needs in this area; in particular, none of the existing trials adequately compare these medications. We would urge, therefore, that further consideration should be given to a formal trial to allow head-to-head comparison of some of the key drugs in a double-blind randomised controlled trial lasting at least 2 weeks, and of sufficient size to draw reasonable conclusions. We would also recommend that any such trial should include a placebo arm. It should also collect good-quality data around sleep outcomes and in particular quality of life and daytime drowsiness. We do not believe that any formal study of risk of dependency is feasible at present.
Finally, the major research issue is perhaps not around the management of short-term insomnia, but around the management of long-term insomnia: considering the frequency of this symptom and its recurring course, the short-term trial of medication and lack of long-term follow-up undermine attempts to develop evidence-based guidelines for the use of hypnotics in this condition, or indeed for its whole management.