Evaluating maternity services: how representative are data collected using a pregnancy diary?

As a part of the evaluation of Nottingham's response to the Changing Childbirth initiative, a cohort of pregnant women were asked to complete diaries, recording their perceptions of events and their feelings over the entire pregnancy period. Before the study began, we were concerned that the diary completion rate could be low and that those completing would be unrepresentative of the population. In this paper, we report the nature of responses to the diary and show that these problems were far less serious than was initially expected. A high degree of coverage was achieved, implying that large numbers of women were sufficiently motivated to maintain detailed records over many months. The research suggests that the diary is a viable method of data capture in such circumstances.