A prospective stepped wedge trial design (Brown & Lilford, 2006; Brown et al., 2008) will be used when implementing the validated patient safety checklist system in the Neurosurgical Department, the Orthopaedic Clinic and the Department of Gynaecology and Obstetrics at HUH. Patients from departments not using the patient safety checklist system serve as controls, this includes the Head and Neck Clinic (HUH), the Thoracic Surgery Section of the Heart Department (HUH) and two hospitals outside our own municipality (Health Trust Førde, and Health Trust Fonna - Haugesund Hospital). Primary end-points to be measured prospectively include length of hospital stay and morbidity and mortality utilizing the ICD-10 codes for complications collected electronically from the hospital patient administrative systems.