Trends in demand for emergency ambulance services in Wiltshire over nine years: observational study.

We carried out this trial in everyday practice. We included thousands of women who might have received the 10 leaflets, but only 70% reported receiving one of them. Studies reported in the systematic review of decision aids were explanatory trials, with the implicit assumption that all patients received the intervention. One conclusion might be that the systematic review showed that decision aids can be effective under certain circumstances but that our study showed that they are not necessarily effective in the real world. The pragmatic nature of our design may have affected the outcome, but that outcome represents a true picture of the impact of introducing the leaflets into routine practice.