Background: Guidelines give recommendations based on synthesis of evidence with the designed purpose to influence a physician's care of the patient.

Objective: What is the degree of agreement between similar bronchiolitis treatment recommendations within different national guidelines?

Design/Methods: Guidelines were searched with MEDLINE, EMBASE, and the grey literature. Recommendations within each guideline were categorized as 1) recommend for 2) optionally recommend 3) abstain from recommending and 4) recommend against a treatment. The degree of agreement between recommendations was evaluated using a weighted Kappa score. Pairwise comparisons of the guidelines were evaluated similarly.

Results: There were 5 guidelines: American Academy of Pediatrics (AAP), Scottish Intercollegiate Guidelines Network (SIGN), Clinical Practice Guidelines in the Spanish National Healthcare System (Spain), Pediatric Society of New Zealand (NZ), and Australian Health for Kids Guideline Development Group (AUS). There were 95 recommendations with 25 recommendations given in > 2 guidelines. The overall weighted Kappa score for the treatment recommendations was 0.91 (CI 0.82,0.98). This demonstrates excellent agreement. Overall agreement between the pairs ranged from the lowest of 0.82 (CI 0.60, 1.00) between the AAP and NZ guidelines to the highest degree of agreement of 0.96 (CI 0.88, 1.00) between the SIGN and Spain guidelines.

Conclusions: Overall, there was excellent agreement of the bronchiolitis treatment recommendations internationally. This suggests that harmonization of guidelines may be possible. Evidence synthesis and guideline generation is labor intensive and expensive. Globalization of well-designed guidelines would conserve resources and allow for greater resource allocation for the timely update of guidelines, and the successful implementation of guidelines at the bedside with consideration of the local prevalence, cost, and patient preferences and values. Any additional efforts and resources could be allocated to new studies to advance the evidence for treatment of this common pediatric condition for which little has been shown to improve the course other than supportive care.