McIlwaine 2013.

Study characteristics
Methods	RCT. Parallel design with 2‐month washout period post randomisation and prior to start of trial. Location: multicentre (12 centres) in Canada. Duration 12 months.
Participants	107 participants (children and adults aged 6 ‐ 47 years) enrolled in the study and randomised. PEP Group: 51 participants (mean age 13.5 years). 25 female, 26 male. HFCWO Group: 56 participants (mean age 14.3 years). 25 female, 31 male. 19 dropouts within the study ‐ 16 occurred prior to or at the time of randomisation (8 from each group ‐ reasons given). At visit 2 (start of treatment arm) 43 were included in the PEP arm and 48 in the HFCWO arm. The study results were analysed on an ITT premise based on these participant numbers. Between visits 2 and 6 there was 1 further dropout from the PEP group and 2 from the HFCWO group. 88 were analysed following completion of the study.
Interventions	1 ‐ 2 sessions/day ‐ participants to remain on individual regimen prescribed prior to study 30 min of HFCWO (6x 5 min cycles) versus PEP (6 cycles of 15 PEP breaths followed by 2 ‐ 3 huffs).
Outcomes	Time to exacerbation and frequency of exacerbation, health‐related quality of life measurements, change in respiratory function parameters, participant preference.
Notes	Only randomised participants were included in the ITT analysis.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised by an independent statistician using a computer‐generated randomisation table.
Allocation concealment (selection bias)	Low risk	Central allocation ‐ computer‐generated by independent statistician.
Blinding (performance bias and detection bias) All outcomes	Low risk	Although participants could not be blinded to treatment, physicians and respiratory therapists performing the respiratory assessments and lung function tests were unaware of the treatment assignment.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Drop outs were reported and data sets for all included were complete. ITT identified. At visit 2 when participants were to begin prescribed arm of treatment, there were 8 dropouts in each arm with similar reasons given. By the end of the study, there was 1 further dropout from the PEP group (diagnosed with CFRD) and 2 treatment‐related from the HFCWO group (1 due to reflux and vomiting associated with treatment; 1 did not like HFCWO).
Selective reporting (reporting bias)	Low risk	On comparison with the protocol published on the clinical trials register, all outcomes identified are reported within the final paper. However, the data are presented as medians and percentiles which makes analysis problematic.
Other bias	Low risk	Both types of device (HFCWO and PEP) were loaned by their respective companies. It is considered therefore that this would not constitute bias as both groups were potentially equally influenced. The study was limited by the fact that the majority of participants were on PEP prior to the study, although attempts were made to limit any potential bias from this by having a washout period.