Evaluating innovations in maternity care: methodological approaches to a baseline postal survey

A network of four public maternity hospitals in Melbourne, Australia, has implemented a range of initiatives aimed at improving maternity care. Comprehensive evaluation aims to determine whether or not the maternity service enhancement strategies have led to improvements in women's views and experiences of care. This paper discusses the baseline survey study design and methodological issues associated with the recruitment and reminder processes.

All women who gave birth over a 14-week period in 1999 at one of the four maternity units, except those who had a stillbirth or neonatal death, were invited to participate in the baseline postal survey. Questionnaires were sent to women at 3 months postpartum. A system of written and telephone reminders was instituted.

The overall response fraction to the baseline survey was 65.2 percent (1256/1922). The sample was representative in terms of maternal age, method of birth, and infant birthweight. Women born overseas of non-English speaking background, single women, and women having their second or subsequent baby were underrepresented.

The pleasing response fraction in part may be attributed to the method of recruitment and the reminder processes. Rigorous and careful approaches to methodology enhance study integrity and provide context to the interpretation of study findings.