Clinical score for the outcome of external cephalic version: a two-phase prospective study.
To design a score based on clinical parameters to predict the outcome of external cephalic versions (ECVs) at term. A two-phase study was conducted (analysis/design and prospective validation) regarding 1000 versions performed between March 2002 and November 2010. The variables considered in the score were selected based on the results of multiple logistic regression models and multiple correspondence analyses published by our group. The predictive capacity was estimated through the area under the ROC curve. The success rates for ECV in phases 1 and 2 were 52.2 and 51.2%, respectively, making the overall success rate 51.7%. The score was designed with the variables parity, placental location, breech variety and amount of amniotic fluid giving a value for each one. A clinical recommendation, based on the result of the score, was the estimated success rate with the 95% confidence interval. The predictive capacity of the score for the outcome of ECV at term was 70.1% (95% CI 66.9-73.4). A score composed of four easily measurable variables enabled us to predict the outcome of ECV at term.