[1] McMaster Univ, Dept Med, Hamilton, ON, Canada
[2] McMaster Univ, Div Respirol, Dept Med, Hamilton, ON, Canada
[3] McMaster Univ, Dept Hlth Res Methods, Hamilton, ON, Canada
[4] McMaster Univ, Div Rheumatol, Dept Med, Hamilton, ON, Canada
[5] McMaster Univ, Respirol, Hamilton, ON, Canada