McIlwaine 2010.

Study characteristics
Methods	RCT. Cross‐over design. Single paediatric centre. Location: Canada.
Participants	36 participants with "proven diagnosis" of CF. Age: 12 ‐ 18 years. Shwachman score 65 ‐ 98. Compliant performing daily chest physiotherapy using PD&P technique for at least 1 year prior to the study.
Interventions	Treatment 1: 2 sessions of AD 30 min daily in sitting. The length of time to complete this technique varied with each participant but on average required 30 minutes. Treatment 2: 2 sessions of PD&P approximately 30 min daily, 6 positions drained in morning and 5 in evening using percussion, deep breathing exercises combined with vibrations on expiration. This was followed by huffs. Each treatment regimen was performed for 1 year before crossing over to the other treatment regimen for a further year.
Outcomes	FEV1, FVC, FEF25-75% sputum weight (partial and subjective), number of hospital admissions, participant preference, and need for extra treatment. A change in Shwachman and Huang scores were also measured.
Notes	The study was powered as a 2‐year cross‐over study. Only data from the first year were reported due to 10/17 participants from Group B (AD‐PD&P) withdrawing from the study before starting PD&P arm; this completely biased the results. “No formal matched cross‐over analysis of the data could be performed.” Also, “...as the study was not powered to detect single group differences, these results may not truly reflect treatment differences.” Sputum weight was not measured by the investigators, but it was the participants who "reported an increased expectoration with AD".
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were matched as pairs, using FEV1 (within 15%) as the primary match, Shwachman scores (within 15 points), age (within 3 years) and same sex as secondary matches. Members of each pair were randomly assigned by computer to 1 of the 2 groups (A or B).
Allocation concealment (selection bias)	Unclear risk	Not stated.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Neither participants nor physiotherapy personnel were blinded to the self‐administered physiotherapy techniques under study. As it is not possible to blind by design, the risk of of bias is deemed to be low.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"...full clinical assessment, including Shwachman and Huang scores, performed at the CF clinic by physician blinded as to the method of physiotherapy the patient was performing in the study...” and “The pulmonary function technician was blinded as to the patient’s physiotherapy technique.” Not stated if statistician was blinded or not.
Incomplete outcome data (attrition bias) All outcomes	High risk	36 participants entered the study. Data on 33 available at 12 months. 3 withdrew from the study in the first year: 2 in Group A (pregnancy, ABPA), 1 in Group B (non‐compliant). In the first year of the study, 33 stayed in the group to which they were randomised. In the 2nd year, 10/17 participants from Group B (AD/PD) did not return for PD&P arm of study, due to preference to continue with AD (completely biased 2nd arm of study). Strong cross‐over effect in 7 participants who continued with the study as they incorporated AD breathing technique into PD&P; therefore only year 1 data reported. The results from the 2nd year could not be analysed as single‐group differences could not be studied. Secondary analysis of PFTs in Group A (PD&P, then AD) comparing years 1 and 2 was performed but no significant differences were found.
Selective reporting (reporting bias)	High risk	“Full clinical assessment” was undertaken and would include weight and height, but these are not reported. Adherence measured by monthly phone calls, but not reported in paper. Likewise, duration of hospitalisations and sputum bacteriology recorded but not reported. Antibiotic use was partially reported (none received home IV antibiotics). FEV1, FEF25-75% and Shwachman scores are fully reported though P values not given and only described as non‐significant. Huang score was significantly improved (P = 0.04) in the AD group versus PD&P group. Baseline FVC and Huang score recorded but unreported.
Other bias	Low risk	None identified.