RACIAL DIFFERENCES
If the race switch on the front panel of the printer is set to 2, the
calculated predicted values are computed as indicated in the tables
on pp. 54-58. If the race setting is set to
1,
the calculated predicted
values are then multiplied by 0.85 (except for FEVi/FVC).
CALCULATING PREDICTED VALUES MANUALLY
The PneumoCheck Printer/Charger calculates predicted values
automatically, and an asterisk is placed in the ABN column if the
actual parameter falls below the lower limit of normal (LLN).
Manual calculations can be made using the procedure and tables
which follow:
All predicted values (except as noted) are calculated using the
formula:
Value = (Fl x age) + (F2 x height) + constant
where the Fl and F2 multipliers and the constant are taken from the
appropriate table entry and height is in centimeters.
For example, using Knudson’s 1983 tables, the predicted normal
FVC for a 20 year old male who was 6’0” tall would be calculated as
follows:
1.
First convert the height to centimeters.
height = 72” x 2.54 cm/inch = 182.9 cm
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