Complex interventions in midwifery care: reflections on the design and evaluation of an algorithm for the diagnosis of labour.

Randomised controlled trials are the 'gold standard' for evaluating the effectiveness of interventions in health-care settings. However, in midwifery care, many interventions are 'complex', comprising a number of different elements which may have an effect on the impact of the intervention in health-care settings. In this paper we reflect on our experience of designing and evaluating a complex intervention (a decision tool to assist with the diagnosis of labour in midwifery care), examining some of the issues that our study raises for future research in complex interventions.