Table 1

FI calculation criteria

FICalculation criteriaExample:
Embedded Image
FIA The higher FEV1 value of the two spirometry manoeuvres at every time point post-hyperpnoea was considered. Of the five post-challenge values, the one showing the greatest decline in FEV1 from baseline was taken for the calculation of FIC. A test was considered positive if the decrease in FEV1≥10%.7

  1. Selection of the higher FEV1 value for all five post-hyperpnoea values (bold black boxes)

  2. Greatest decline of the five selected post-hyperpnoea values=−17.6%

  3. Diagnostic classification using FIA: EVH+ indicates EIB+.

FIB The higher of two FEV1 values for each time-point following hyperventilation was identified. If the decrease in FEV1≥10% at two consecutive time points, a test was considered EVH+. The higher FEV1 value of the two was reported as the FI.8 9

  1. Selection of the higher FEV1 value for all five post-hyperpnoea values (bold black boxes)

  2. Check if FEV1 values at two consecutive time points among the selected five post-hyperpnoea values≥10%. Greatest fall in FEV1 at 3 and 5 min post-hyperpnoea, but FIB≥10% only at one single time point. Report lower of the two values as FIB=−8.8%

  3. Diagnostic classification using FIB: negative EVH test indicates EIB-.

FIC The FI was normalised to VEEVH-achieved using the following equation:
FIC = (Embedded Image ) • (Embedded Image )• 100
FEV1baseline – FEV1post-EVH was determined identically to FIA.10

  1. Determine achieved minute ventilation during EVH challenge (VEEVH-achieved) = 90 L/min

  2. Adjust FIA for VEEEVH-achieved using equation:

    FIC = (Embedded Image ) • (Embedded Image )• 100=20.0%

  3. Diagnostic classification using FIC: positive EVH test indicates EIB+.

  • EVH, eucapnic voluntary hyperpnoea; EIB , exercise-induced bronchoconstriction; FEV1, forced expiratory volume in 1 s; FI, fall index.