Welch Allyn Schiller AT-2plus, Manual

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AT-2plus User Guide Spirometry Supplement Page 27
Art. No. 2. 510339wa ©1999
AT-2plus User Guide Spirometry Supplement Page 27
Art. No. 2. 510339wa ©1999
Diagnosis
Diagnosis Setting `American`
For the USA and Canada, diagnosis of possible respiratory problems is based on the ITS interpretation standard which uses the LLN
(Lower Limits of Normal) calculations. These calculations apply to patients between the ages of 5 and 85. The LLN FEV1% value is
calculated as follows:
Male Female
Adult >26 yrs: Predicted FEV1% -9.2 >21 yrs: Predicted FEV1% -11.1
Adolescent 19 to 25 yrs: Predicted FEV1% x 0.848 19 to 20 yrs: Predicted FEV1% x 0.805
Child <18 yrs: Predicted FEV1% x 0.826 <18 yrs: Predicted FEV1% x 0.791
Using this LLN value, the diagnostic statements and their criteria are as follows:
Diagnosis Criteria
Normal limits FEV1/FVC% predicted is >80%
Borderline Obstruction FEV1/FVC% is 80 to 100% of LLN
Mild Obstruction FEV1/FVC% is 60 to 80% of LLN
Moderate Obstruction FEV1/FVC% is 40 to 60% of LLN
Severe Obstruction FEV1/FVC% is <40% of LLN
Mild Restriction %FVCpredicted is 60 to 80%
Moderate Restriction %FVCpredicted is 50 to 60%
Severe Restriction %FVCpredicted is <50%
Diagnosis
Diagnosis Setting `American`
For the USA and Canada, diagnosis of possible respiratory problems is based on the ITS interpretation standard which uses the LLN
(Lower Limits of Normal) calculations. These calculations apply to patients between the ages of 5 and 85. The LLN FEV1% value is
calculated as follows:
Male Female
Adult >26 yrs: Predicted FEV1% -9.2 >21 yrs: Predicted FEV1% -11.1
Adolescent 19 to 25 yrs: Predicted FEV1% x 0.848 19 to 20 yrs: Predicted FEV1% x 0.805
Child <18 yrs: Predicted FEV1% x 0.826 <18 yrs: Predicted FEV1% x 0.791
Using this LLN value, the diagnostic statements and their criteria are as follows:
Diagnosis Criteria
Normal limits FEV1/FVC% predicted is >80%
Borderline Obstruction FEV1/FVC% is 80 to 100% of LLN
Mild Obstruction FEV1/FVC% is 60 to 80% of LLN
Moderate Obstruction FEV1/FVC% is 40 to 60% of LLN
Severe Obstruction FEV1/FVC% is <40% of LLN
Mild Restriction %FVCpredicted is 60 to 80%
Moderate Restriction %FVCpredicted is 50 to 60%
Severe Restriction %FVCpredicted is <50%