Homnick 1995.

Study characteristics
Methods	Single‐centre (Michigan, USA), parallel design RCT 20 participants stratified by Shwachman score and randomised to either IPV with intrained aerosol or standard manual chest physiotherapy and aerosol treatment for a total study period of 180 days. Participants were instructed to do ≥ 2 treatments each day and were followed up every 30 days.
Participants	20 participants with CF who attended the CF centre and who were using standard CPT and aerosol therapy at home were randomised. They were clinically stable, ambulatory, with no history of pneumothorax or haemoptysis, and able to tolerate ≥ 2 IPV or standard CCPT sessions per day. Age range aged 5–24 years CCPT (n = 8): 5 males, 3 females, mean age 10 years; range 5–18 years IPV (n = 8): 5 males, 3 females, mean age 12 years; range 5–24 years
Interventions	CCPT: aerosol and CCPT ≥ 2 times a day recorded daily on a log sheet. This consisted of manual percussion for about 2 min in each of 10 PD positions. Standard aerosol therapy with 2 mL saline or odium cromoglicate with an appropriate amount of albuterol given by compressor and updraft nebuliser. IPV with intrained aerosol: participants received instructions on the use of the IPV (10–30 cmH2O) machine and were given saline and albuterol for use in the device. Instructed to use IPV ≥ 2 times a day and record the frequency daily on a log sheet. The IPV group also asked to complete a satisfaction index after each 30‐day period of using IPV (comfort, time spent in therapy and compliance). Dosing for albuterol in both the standard aerosol and IPV groups was 1.25–2.5 mg per treatment. Pressures and frequencies were individually determined by the respiratory therapist. All participants continued their assigned treatments while hospitalised, usually at a frequency of 4 times per day.
Outcomes	All participants were followed up at 30‐day intervals, measures included participant logs, anthropometric measures (BMI), spirometry (FVC, FEV1, FEF25–75), adverse effects, satisfaction, inpatient and outpatient antibiotic use, number of hospitalisations and adverse events. An adverse reaction was reported in 1 participant who experienced minor haemoptysis in the 4th week of using the IPV device.
Notes	Study reported in 1 abstract (Homnick 1994) and 1 full‐text manuscript (Homnick 1995), which is the primary reference for this study. Jadad score: 1/5.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Not reported. Participants were randomised after being stratified by Shwachman score.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not feasible (participants), not described (personnel).
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	8 participants in each group completed study, but no details given on 4 withdrawals.
Selective reporting (reporting bias)	Unclear risk	All outcomes were reported, but each participant participated in 5 sequential 30‐day periods, with outcomes measured on each 30 visit. Only first and last visits were analysed and reported.
Other bias	High risk	Only IPV group asked to report on satisfaction. Only 8 participants completed study in each group. Details of, or reasons for, 4 dropouts not reported. Baseline mean BMI was significantly higher in the IPV group (15.2 (SD 1.7)) compared to the CCPT group (7.9 (SD 2.0)) and mean FEV1 (although non‐significant) was higher in the IPV group (70 (SD 12) % predicted) compared to the CCPT group (59 (SD 12) % predicted).