Placidi 2006.

Methods	RCT. Cross‐over design. Duration: treatment 2x daily for 70 min for 2 days per intervention.
Participants	17 participants with CF. Severe lung disease. Acute participants. Mean (SD) age: 27 (7) years. FEV₁ % predicted mean (SD): 25% (6). BMI mean (SD): 18 (3) kg/m². MIP % predicted mean (SD): 87% (17). Wet weight sputum mean (SD): 5 (5) g.
Interventions	Intervention 1: directed cough; Intervention 2: PEP via nasal mask. Intervention 3: CPAP via nasal mask; Intervention for NIV with IPAP 8 ‐ 12 cm H₂O; EPAP 4 cm H₂O.
Outcomes	Sputum wet and dry weight; number spontaneous coughs; FEV₁; FVC; FEF; mean SpO₂; participants subjective impression of the effectiveness and fatigue induced by each treatment.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation of treatment order was done according to the Latin square design which provided a balanced assignment to each treatment and a balance in the sequence of treatments.
Allocation concealment (selection bias)	Unclear risk	Not discussed.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Physiotherapists collected sputum and the technician was blinded to physiotherapy treatment but it is not identified who was responsible for weighing sputum or collating cough information induced by the treatment.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	All participants were accounted for.
Selective reporting (reporting bias)	Low risk	All outcome measures were reported.
Other bias	Unclear risk	Methods of statistical analysis were described.