An evaluation of preinduction scoring systems.

A double-blind clinical study of five preinduction scoring systems was undertaken to determine the accuracy of clinical usefulness of each system as applied to a diverse group of patients. When strictly applied, all five systems were found to be as accurate and useful as it was originally claimed they were. However, when applied without regard to each author's prerequisites, none of the five scoring systems was found to be reliable. A series of preinduction score modifiers is presented which, when applied to any of the preinduction scoring systems, will reliably predict the outcome of induction of labor, with a 50% induction failure rate in patients with lower third scores, a 10% failure for middle third scores, and essentially a 0% failure in the upper third scores.