Table 1.

Study inclusion and exclusion criteria

Inclusion criteria
  • Age >12 years

And at least one of the following:
  • Rhinorrhea

  • Sore throat

  • Sneezing (during this illness)

  • Cough (acute, chronic, or productive)

  • Wheeze

  • Fever

  • Shortness of breath

  • New-onset hoarse voice (during this illness)

Exclusion criteria
  • Lack of consent

  • Ventilatory support

  • Terminal disease

  • Medical contraindication to voluntary coughing:

    • Severe respiratory distress

    • History of pneumothorax

    • Eye chest or abdominal surgery in the past 3 months

  • Uncontrolled acute heart failure (chronic heart failure was not an exclusion)

  • History of neuromuscular disease

  • History of lobectomy/pneumonectomy

  • Diagnosed chronic obstructive pulmonary disease or restrictive lung disease