Methods of classification for women undergoing induction of labour: A systematic review

Abstract

Background: The lack of reproducible methods for classifying women having an induction of labour (IOL) has led to controversies regarding the association of IOL and health outcomes for mother and baby. Objectives: To identify research papers that describe a methodology for classifying women having an IOL, and to evaluate the utility of these methods of classification for clinical, research and surveillance purposes. Search strategy: We conducted electronic searches in CINAHL, EMBASE and WEB of KNOWLEDGE from database inception until Oct 2013 and searched reference lists. Selection criteria: Two reviewers independently assessed eligibility. Studies had to describe a method for classifying women with an IOL using a minimum of two categories, regardless of whether or not this was the main purpose of the study. Data collection: Data were extracted on study characteristics, quality and results. Pre-specified criteria were used to evaluate the utility of these methods of classification for IOL. Main results: Seven studies met the inclusion criteria. All studies categorised women according to the presence or absence of a medical indication for IOL. Uncertainties and/or deficiencies were identified across all methods of classification related to the criteria of total inclusivity, reproducibility, clinical utility, implementability and data availability limiting their usefulness. Conclusion: Current methods of classifying women with an IOL are inadequate for clinical, research and surveillance purposes. Limitations with classification systems based on medical indications suggest that an alternative method of classification is required for women having IOL.