RT Journal Article
SR Electronic
T1 Validity and interpretation of mortality, health service and survey data on COPD and asthma in England
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 279
OP 286
DO 10.1183/09031936.03.00006102
VO 21
IS 2
A1 A. Hansell
A1 J. Hollowell
A1 R. McNiece
A1 T. Nichols
A1 D. Strachan
YR 2003
UL http://erj.ersjournals.com/content/21/2/279.abstract
AB The comparability of asthma and chronic obstructive pulmonary disease (COPD) epidemiology in different English routine data sources was examined to explore their use and validity in investigating environmental influences on respiratory health. National data were obtained for mortality, emergency hospital admissions, general practitioner contacts and symptoms in the early 1990s. Age/sex patterns, seasonal variations and regional and urban/rural age/sex standardised event ratios were examined. Spearman rank correlations were used to describe consistency of regional rankings across data sets. Asthma showed inconsistent disease patterns in different data sources and weak correlations for regional rankings but COPD was notably consistent. Unmeasured confounders may partly explain the findings, but individual level adjustment for social class and smoking (possible for symptoms) only partially attenuated the higher COPD rates in northern and urban areas and did not affect findings for asthma. When epidemiological patterns are consistent across data sources as with chronic obstructive pulmonary disease in England, healthcare use is likely to reflect the underlying prevalence and severity of disease and can be used to study environmental influences. When patterns vary, as with asthma, the validity of the data in relation to its intended use must be carefully considered. This study was funded by the Department of Health.