Methodology

This guideline was originally developed in 2016. The scope of the guideline has been expanded in this 2025 update to include recommendations on respiratory syncytial virus (RSV) prevention, the management of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) co-infection, and bronchiolitis management in intensive care settings (up to but not including intubation). Forty-one recommendations have been developed on 25 topics by 29 clinical and methodological experts from Australasia serving within the overseeing Guideline Advisory Group (GAG) and the consultative Guideline Development Committee (GDC). The recommendations were based on systematic reviews (final search 24 January 2024), and appraisals of the evidence using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Each recommendation was finalised through consensus discussion and voting of the GAG/GDC, who considered the balance of benefits and harms, resource implications, feasibility in the Australasian context, acceptability, interest-holder values and preferences, and the equity and human rights implications of the proposed action.

The implications of the recommendations for bronchiolitis diagnosis and management are summarised below. For detailed information of the underlying evidence, please refer to the guideline report and annex. Explanation of the recommendation strength and evidence quality definitions are described in the tables below.

GRADE recommendation strength and evidence quality definitions

Recommendation strength Definition Recommendation language
Strong The GDC is confident that the desirable effects of the action outweigh its undesirable effects, or vice versa. Most or all individuals will be best served by the recommended course of action. “Use…”
“Do not…”
“Clinicians should…”
Weak The desirable effects of the action probably outweigh the undesirable effects, or vice versa, but appreciable uncertainty exists. Not all individuals will be best served by the recommended course of action. “Consider…”
“Do not routinely…”
Conditional A weak recommendation where the recommended course of action may depend on patient factors, resources or setting.
Consensus-based recommendation A recommendation formulated through GAG and GDC consensus in the absence of evidence, where a systematic review of the evidence was conducted as part of the search strategy.

 

Evidence quality ratings Contributing factors
⊕⊕⊕⊕
High
  • Risk of bias (↓ or ↓↓)
  • Inconsistency of results (↓ or ↓↓)
  • Indirectness of evidence (↓ or ↓↓)
  • Imprecision (↓ or ↓↓)
  • Publication bias (↓ or ↓↓)
  • Large magnitude of effect (↑ or ↑↑)a
  • Plausible confounding would reduce the demonstrated effect (or increase the effect if no effect observed) (↑)a
  • Demonstrated dose-response gradient (↑)a
⊕⊕⊕⊖
Moderate
⊕⊕⊖⊖
Low
⊕⊖⊖⊖
Very low
Not applicable (NA) No eligible evidence

GDC = Guideline Development Committee; GAG = Guideline Advisory Group. Reproduced from the GRADE Handbook. For further detail, refer to the guideline report methodology section. High quality= no downgrades, or observational evidence* with ≥2 upgrades; moderate quality= one downgrade, or observational evidence* with 1 upgrade; low quality= two downgrades, or observational evidence* with no upgrades; very low quality= ≥3 downgrades, or observational evidence* with ≥1 downgrade.  *For topics where RCT evidence was sought, observational evidence is downgraded to low quality at the outset.  aOnly for observational evidence without downgrades for the subsequent five domains.

References

1. GRADE handbook for grading quality of evidence and strength of recommendations: The GRADE Working Group; 2013. Available from: guidelinedevelopment.org/handbook.

2.  PREDICT. Australasian Bronchiolitis Guideline: 2025 Update. Melbourne, VIC, Australia; 2025.