Conesa‐Segura 2018.

Study characteristics
Methods	Randomised, double‐blind controlled clinical trial
Participants	Children under the age of 2 years, admitted to hospital for acute viral bronchiolitis, absence of congenital cardiopathy, and no contraindication for thoracic physiotherapy techniques. Diagnostic criteria were not reported; however, they cited a study (Scarfone RJ. Controversies in the treatment of bronchiolitis. Curr Opin Pediatr 2005; 17: 62–6). Country: Spain. N = 77 participants randomised and 71 participants analysed: 42 allocated to the respiratory physiotherapy group, and 35 to the control group. Mean age was 2.9 months (range 1.8 to 5.4). There was no information on percentage of RSV+ participants.
Interventions	Group 1: respiratory physiotherapy group. Slow expiration technique + coughing + retrograde rhinopharyngeal unclogging (forced inspiratory manoeuvre) + nasal and oral aspiration in order to remove secretions. The treatment was given once a day during the stay in infant’s unit, and total duration of treatment was about 15 minutes (N = 39). Group 2 (control group): no physiotherapy (N = 32) All participants received hypertonic saline nebulisation, and the nasopharynx content was aspirated. No drug was prohibited during study and they were prescribed freely by paediatricians.
Outcomes	Primary outcome: Acute Bronchiolitis Severity Scale score and O2 saturation, recorded shortly after each intervention during the stay and at medical discharge, and the hospital stay. Higher values indicate increased severity. Secondary outcomes: subjective opinion of parents or tutors at the end of treatment
Notes	All infants were assessed daily at 3 time points: baseline (at 8.00 a.m.) and 10 minutes and 2 hours after physiotherapy intervention in Groups 1 and 2, until discharge. They were also evaluated at discharge. Authors report no funding. ClinicalTrials.gov identifier: NCT02458300
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	A researcher did a simple randomisation by assigning participants to either the respiratory physiotherapy group or the control group (Macro!RNDSEQ for SPSS Statistics. Generation of Random Sequences [computer program]. V2011.09.09. Randomisation seed = –1987653.97)
Allocation concealment (selection bias)	Low risk	The allocation was concealed by the primary researcher.
Blinding (performance bias and detection bias) All outcomes	Low risk	Evaluating paediatricians, parents, and statistician were unaware of the group codes.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	6 out of 77 participants excluded from analysis. Flow of participants described. Number of participants excluded from analysis unlikely to impact on results or conclusions.
Selective reporting (reporting bias)	Unclear risk	Study protocol was published in ClinicalTrials.gov, and methods agree with publication. However, publication presents oxygen saturation as a primary outcome, when it was not reported as such in the protocol, and omits a secondary outcome established in protocol (subjective opinion). Regardless, we considered that these changes did not bias reporting.
Other bias	Low risk	No other biases identified.