Group 1 (total group) | Group 2 (exclusions) | Group 3 (met criteria) | Group 4 (usable) | |||||
---|---|---|---|---|---|---|---|---|
1084 | 565 | 519 | 989 | |||||
N | Per cent | 95% CI | Per cent | 95% CI | Per cent | 95% CI | Per cent | 95% CI |
Spirometric obstruction* | 16.8 | 14.6 to 19.2 | 27.6 | 24.0 to 31.5 | 5.0 | 3.3 to 7.3 | 17.6 | 15.3 to 20.1 |
Spirometric restriction* | 4.5 | 3.4 to 5.9 | 3.2 | 1.9 to 5.0 | 6.0 | 4.1 to 8.4 | 3.9 | 2.8 to 5.4 |
Mixed disease* | 2.9 | 2.0 to 4.0 | 4.6 | 3.0 to 6.7 | 1.0 | 0.3 to 2.2 | 2.9 | 2.0 to 4.2 |
All spirometric restriction* | 7.4 | 5.8 to 9.1 | 7.8 | 5.7 to 10.3 | 6.9 | 4.9 to 9.5 | 6.9 | 5.4 to 8.6 |
VA restriction* | 5.9 | 4.6 to 7.5 | 5.0 | 3.3 to 7.1 | 6.9 | 4.9 to 9.5 | 5.7 | 4.3 to 7.3 |
Low DL,CO without obstruction* | 9.0 | 7.4 to 10.9 | 8.3 | 6.2 to 10.9 | 9.8 | 7.4 to 12.7 | 9.2 | 7.5 to 11.2 |
Spirometry & VA† | 2.6 | 1.7 to 3.7 | 1.8 | 0.9 to 3.2 | 3.5 | 2.1 to 5.4 | 2.4 | 1.6 to 3.6 |
Spirometry & DL,CO‡ | 1.3 | 0.7 to 2.2 | 0.7 | 0.2 to 1.8 | 1.9 | 0.9 to 3.5 | 1.2 | 0.6 to 2.1 |
VA & DL,CO § | 2.3 | 1.5 to 3.4 | 1.4 | 0.6 to 2.8 | 3.3 | 1.9 to 5.2 | 2.3 | 1.5 to 3.5 |
Spirometry & VA & DL,CO¶ | 1.1 | 0.5 to 1.9 | 0.5 | 0.1 to 1.5 | 1.7 | 0.8 to 3.3 | 1.0 | 0.5 to 1.9 |
Spirometry or VA** | 7.8 | 6.3 to 9.6 | 6.4 | 4.5 to 8.7 | 9.4 | 7.1 to 12.3 | 7.2 | 5.7 to 9.0 |
Spirometry or DL,CO†† | 12.3 | 10.4 to 14.4 | 10.8 | 8.4 to 13.7 | 13.9 | 11.0 to 17.2 | 11.9 | 10.0 to 14.1 |
VA or DL,CO‡‡ | 12.6 | 10.7 to 14.8 | 11.9 | 9.3 to 14.8 | 13.5 | 10.7 to 16.7 | 12.5 | 10.5 to 14.8 |
Spirometry or VA or DL,CO§§ | 14.4 | 12.6 to 16.6 | 13.1 | 10.4 to 16.2 | 15.8 | 12.8 to 19.2 | 13.9 | 11.8 to 16.2 |
Per cent—prevalence of lung function patterns in each population group in percentage.
95% CI—Clopper-Pearson (exact) 95% confidence limits of prevalence estimates.
Group definitions are as described in the Methods section.
*Definitions described in the Methods section.
†After excluding spirometric obstruction, both FVC and VA were <LLN.
‡This is the proportion of spirometric restriction that also had a reduced (<LLN) DL,CO.
§This is the proportion of VA restriction that also had a reduced (<LLN) DL,CO.
¶After excluding spirometric obstruction, FVC, VA and DL,CO were <LLN.
**After exclusion of spirometric obstruction, either FVC or VA were <LLN.
††After exclusion of spirometric obstruction, either FVC or DL,CO were <LLN.
‡‡After exclusion of spirometric obstruction, either VA or DL,CO were <LLN.
§§After exclusion of spirometric obstruction, either FVC or VA or DL,CO were <LLN.
DL,CO, diffusing capacity; FVC, forced vital capacity; LLN, ; VA, alveolar volume.