Understanding WHO surgical checklist implementation: tricks and pitfalls. An observational study.

Background: The purpose of the present study was to assess the reliability of implementation data regarding the surgical safety checklist (SSC) and to identify which factors influence actual implementation.

Methods: The study was a retrospective record-based evaluation in a regional network of nine Spanish hospitals, combined with a complementary direct-observation study that included a survey of the surgical teams' attitudes. SSC compliance and associated factors were assessed and compared in a retrospective sample of 280 operations and a concurrent sample of another 85 surgical interventions.