Study designs of evaluations included in the review
The studies needed to be comparative, prospective and randomised. They had to include an appropriate statistical analysis and report precise statistical data (no further details were provided). Systematic reviews and meta-analyses were also accepted.
Specific interventions included in the review
No specific inclusion criteria for the interventions were given, apart from that the intervention needed to be clinically applicable. The included interventions used beta-2 mimetics, atropinic agents and adrenergic agents.
Participants included in the review
Infants aged 1 to 24 months who were affected by a first or second episode of acute bronchiolitis were included in this review. Asthmatics and those with acute respiratory insufficiency were excluded. The study population needed to correspond to those usually seen in clinical practice.
Outcomes assessed in the review
No specific inclusion criteria for the outcomes were given. The outcomes described in the review were:
the improvement of respiratory distress clinical scores, in particular the respiratory distress assessment instrument, which measures respiratory frequency, wheezing and retraction signs;
the rate of hospitalisation;
the length of hospital stay;
the variation in transcutaneous oxygen saturation; and
criteria estimating resistance and airway flow.
How were decisions on the relevance of primary studies made?
The author does not state how the papers were selected for the review, or how many of the reviewers performed the selection.