A Delphi Study to Explore the American Association of Critical-Care Nurses Level of Evidence Resource

Evidence-based practice integrates research evidence, clinical expertise, and patient preferences. The American Association of Critical-Care Nurses (AACN) pioneered evidence-based practice, developing one of the first evidence hierarchy resources for its members to rank the strength of evidence for practice recommendations.

To evaluate use of the AACN levels of evidence resource and make recommendations for its use, and to explore opportunities to improve the resource.

A 3-round Delphi approach guided by consensus-building theory, where consensus meant ≥80% agreement.

Twelve nurse experts in evidence-based practice completed 3 survey rounds. Most participants (83%) worked in clinical settings and were doctorally prepared. In round 1, 83% recommended revisions and 67% advocated changing the hierarchy structure from alphabetical letters to Roman numerals. The resource was used to rank individual pieces of evidence and to rank practice recommendations based on synthesized evidence. Clearer definitions were suggested for qualifying statements. In round 2, 83% of participants supported a synthesis tool for best evidence and development of detailed instructions. Additional sources of evidence were suggested and ranked. In round 3, 75% of participants indicated preferences for the order of research and nonresearch evidence. Experts were divided on continued use of manufacturers' recommendations as an evidence source.

This study validated AACN's levels of evidence resource with major revisions to maintain relevancy and usefulness. To facilitate use, additional resources to support the evaluation of quality, strength, and synthesis of evidence are recommended.