Measurement technique influences the response of transfer factor (TICO) to XXXX in @entity1 with airflow limitation.

@entity1 @entity1223 @entity1353 @entity3045 @entity1514 @entity133
@entity1353 using a multibreath estimate of @entity133 (TI) was measured before and after @entity3045 in twenty @entity1 with reversible airflow limitation. The effective breathholding time was calculated by four methods due respectively to Ogilvie and colleagues as modified by the American @entity1514 Society (ATS), ATS Epidemiological Standardization Project (ESP), Jones and Meade in which allowance was made for the time of sample collection and a simplified method in which the allowance for sampling was in terms of volume, not time. Two @entity1 could perform the test procedure only after @entity3045 . Amongst the remainder the transfer factor calculated using a single-breath estimate of @entity133 (TI') was on average 12% less than TI. @entity1223 transfer coefficient (KCO), TI and TI' were highest by the ESP method and lowest by the Ogilvie method. Inhalation of @entity3045 (200 gamma) did not affect TI' by any method or TI and KCO by the Jones and Meade method but results by the other methods were reduced; in the case of the modified Ogilvie method the reduction was 3.9%. This error was due to overestimation of effective breathholding time by neglecting the reduction of 39% which occurred in the time of sample collection. The time of inspiration was unchanged whilst the time of deadspace washout was reduced by 16%. After bronchodilatation the absence of a change in TI' was due to the overestimation of effective breathholding time being offset by an increase in the proportion of @entity133 measured by the single-breath procedure.(ABSTRACT TRUNCATED AT 250 WORDS)
