TABLE 3.
Outcomes reported in studies included in this scoping review. Outcomes are classified according to the 38-domain COMET taxonomy
| Core area | Outcome domain | Outcome | n (%) |
|---|---|---|---|
| Death | Mortality/survival | Survival | 4 (5) |
| Physiological/clinical | Physiological/clinical | Cough strength (e.g. peak cough flow) | 48 (64) |
| Lung volume (e.g. vital capacity, forced vital capacity, forced expiratory volume, expiratory reserve volume) | 48 (64) | ||
| Insufflation capacity (e.g. maximum insufflation capacity, lung insufflation capacity) | 22 (29) | ||
| Respiratory muscle strength (e.g. maximal inspiratory pressure, maximal expiratory pressure, sniff nasal inspiratory pressure) | 16 (21) | ||
| Oxygen levels (e.g. saturation of peripheral oxygen) | 15 (20) | ||
| Air flow (e.g. peak expiratory flow, forced expiratory flow) | 13 (17) | ||
| Respiratory rate | 8 (11) | ||
| Carbon dioxide levels | 6 (8) | ||
| Lung expansion/compliance | 5 (7) | ||
| Heart rate | 5 (7) | ||
| Airway pressure (e.g. peak inspiratory pressure, peak expiratory pressure, transpulmonary pressure) | 3 (4) | ||
| Cough volume | 2 (3) | ||
| Mean arterial pressure | 2 (3) | ||
| Airway resistance | 2 (3) | ||
| Other# | 14 (19) | ||
| Life impact | Global quality of life | Quality of life | 3 (4) |
| Functioning | Breathlessness | 3 (4) | |
| Impact on functional ability | 3 (4) | ||
| Job/school absence | 2 (3) | ||
| Fatigue | 1 (1) | ||
| Delivery of care | Comfort | 6 (8) | |
| Patient satisfaction | 4 (5) | ||
| Adherence to secretion clearance techniques | 3 (4) | ||
| Patient-reported cough strength | 2 (3) | ||
| Impact of delivering secretion clearance technique on caregiver | 2 (3) | ||
| Patient-reported effectiveness of secretion clearance | 1 (1) | ||
| Side effects of treatment | 1 (1) | ||
| Resource use | Resource use | Admissions to hospital due to respiratory illness | 13 (17) |
| Respiratory illnesses | 8 (11) | ||
| Supplementary secretion clearance treatments | 4 (5) | ||
| Use/duration of antibiotics | 4 (5) | ||
| Amount of medication for secretion clearance in a treatment session | 1 (1) | ||
| Doctor visits | 1 (1) | ||
| Adverse events | Adverse events/effects | Adverse events | 3 (4) |
Data are presented as n (%) out of a total of 75 studies. COMET: Core Outcome Measures in Effectiveness Trials [21]. Proportions do not always sum to 100% as multiple outcomes were used in some studies. #: including airway collapsibility, sputum weight, effective cough time, effective suctioning, rapid shallow breathing index, inspiratory/expiratory time, lung aeration, need for tracheostomy, invasive ventilation/noninvasive ventilation time, deposition of inhaled particles, ventilator-free breathing ability, pulmonary perfusion, seizures and sleep efficiency/sleep disordered breathing.