W orld H ealth O rganisation (WHO ) has introduced a surgical safety checklist that has reduced post‐operative morbidity and mortality. Prior to national checklist implementation, we assessed its possible impact on the operating room (OR ) process, safety‐related issues and communication among surgical staff in a high‐income country.

In four university and teaching hospitals, a structured questionnaire was delivered to OR personnel involved in consecutive operations over 4–6 weeks before and after the checklist implementation. The questionnaire resembled the WHO checklist and comprised multiple‐choice questions relating to performance of safety checks and communication. Anaesthesiologists (A ), surgeons (S ) and circulating nurses (CN ) answered the questions independently. The WHO checklist was modified for national needs.

Questionnaires were returned from 1748 operations, 901 before and 847 after the checklist. Patient's identity was more often confirmed (A : 62.7% vs. 84.0%, S : 71.6% vs. 85.5%, CN : 81.6% vs. 94.2%, P  < 0.001) and knowledge of names and roles among team members (A : 65.7% vs. 81.8%, S : 71.1% vs. 83.6%, CN : 87.7% vs. 93.2%, P  < 0.01) improved with the checklist. Anaesthesiologists and surgeons discussed critical events pre‐operatively (A : 22.0% vs. 42.6%, S : 34.7% vs. 46.2%, P  < 0.001) more frequently after the checklist. In addition, fewer communication failures (43 vs. 17, P  < 0.05) were reported with checklist.

The checklist increased OR teams’ awareness of patient‐related issues, the procedure and expected risks. It also enhanced team communication and prevented communication failures. Our findings support use of the WHO checklist in various surgical fields.