Table 1.

Summary of Population, Concept, and Context (PCC) Search Terms

PCC Element	Definition	Search Term
Population	Important characteristics of participants: ● Adults >18 years ● Respiratory distress	● Respiratory distress.mp ● Respiratory failure.mp ● Dyspnoea.mp ● Dyspnea.mp ● Interstitial syndrome.mp ● COPD.mp ● Chronic obstructive pulmonary disease.mp ● Pneumothorax.mp ● Pleural effusion.mp ● Consolidation.mp
Concept	Interventions/phenomena of interest/outcomes: ● Lung ultrasound ● Interpretation ● Image quality	● Lung Ultraso*.mp ● Thoracic ultraso*.mp ● Chest ultraso*.mp ● Sonography.mp ● Ultraso*.mp ● Diagnostic imaging.mp ● POCUS.mp ● Prehospital ultraso*.mp ● Portable ultraso*.mp ● Emergency ultraso*.mp
Context	Details about the setting: ● Out-of-hospital setting ● Paramedics	● Emergency medical technicians.sh ● Emergency services.sh ● Emergency medical services.sh ● Ambulances.sh ● Out-of-hospital.tw
		● Pre-hospital.tw ● Pre-hospital.tw ● Paramedic*.tw ● EMT.tw ● EMS.tw ● Air ambulance.tw ● Ambulance.tw ● First responder*.tw ● Emergency medical technicians.tw ● HEMS.tw ● Field triage.tw