text: 2,090 (73.2%) had normal 
  spirometry 
  172 (6.0%) had PRISM 
  
  Figure 1 – Study ﬂow diagram demonstrating the case ﬁnding and control group recruitment and allocation. ASQ ¼ Asthma Screening Questionnaire; 
  COPD-DQ¼ COPD Diagnostic Questionnaire; CF ¼ cystic ﬁbrosis; MI ¼ myocardial infarction; PRISM ¼ preserved ratio impaired spirometry. 