System Interpretation; Nlhep System Interpretation - NDD EasyOne-CS Manuel De L'utilisateur

2030434-002 Rev. B

10 System Interpretation

The diagrams below describe how the interpretation is determined (see references [4], 12],[13]). Auto-
matic interpretation (Setting: NLHEP or optional GOLD/Hardie) can be activated or deactivated under
"Configuration" (see Chapter 8).

10.1 NLHEP System Interpretation

START
no
test session
good
yes
yes
FEV1/FVC
>= LLN
no
yes
FEV1
>= LLN
no
yes
FEV1 >= 60%
predicted
no
yes
FEV1 >= 40%
predicted
no
Notes: 1. LLN = Lower Limit of Normal
2. Where FVC is indicated in chart FEV6 may be substituted, if used.
3. Where there is no lower limit of normal (LLN) defined within the selected predicted normal, the value used for
LLN is calculated as Predicted Value – 1.645 x SEE (standard error of the estimate). If SEE is not defined LLN of
FEV1/FVC is set to 90% of Predicted Value, LLN of FEV1 is set to 80% of Predicted Value; LLN of FVC is set to
80% of Predicted Value.
4. If the quality grade is D and the results are within normal limits, the interpretation states "normal, but the re-
ported values should not be used for comparisons with previous or subsequent tests."
Caution: Interpret with care
no
FVC < LLN
yes
low vital capacity possibly due
to restriction of lung volumes
and low vital capacity possibly
normal spirometry
normal spirometry
mild obstruction
moderate obstruction
severe obstruction
due to restriction of lung vol.
4
4
FVC <LLN
yes
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