4. Study results grouped by outcome measures and interventions – cough augmentation therapy compared to standard care.

Outcome measure	Study identifier Sample size Data presentation	Unassisted cough	Manual BS	Standard care	Between‐group differences
Number and duration of unscheduled hospital and ICU admissions	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported
Unassisted PCF	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported
Health‐related quality of life	Katz 2019 n = 67 Pediatric Quality of Life Inventory score	—	Not reported	Not reported	No results reported
FVC	Katz 2019 n = 67 Median % predicted	85.5 (entire cohort)a	4.1% change	6.4% change	Adjusted MD 2.0, 95% CI –8.2 to 12.3
Time to 10% decline in FVC	Katz 2019 n = 67 Not reported	—	Data not reported	Data not reported	Manual BS vs standard care: P = 0.5
Maximal inspiratory or insufflation capacity	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported
MEP	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported
MIP	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported
Number and duration of outpatient oral antibiotic courses	Katz 2019 n = 67 Units not specified	—	Not reported	Not reported	No results reported

BS: breathstacking; CI: confidence interval; FVC: forced vital capacity; ICU: intensive care unit; MD: mean difference; MEP: maximal expiratory pressure; MIP: maximal inspiratory pressure; n: number of participants; PCF: peak cough flow.

^aBaseline value – not a randomly assigned control