Identifying how best to identify pneumonia and differentiate pneumonia from asthma and chronic obstructive pulmonary disease exacerbations in routine primary care data

Date of Approval
Application Number
Technical Summary

Routinely collected electronic health and administrative data of patients is a valuable tool for health and epidemiological research. The validity and generalisability of any research findings using patients’ electronic health records (EHR) depends on accurate diagnosis of disease outcomes. Validation of various respiratory disease outcomes (e.g., pneumonia, COPD exacerbations (AECOPD) and asthma exacerbations) have been carried out by many studies. However, there is a paucity of data around accurate differentiation of pneumonia events from AECOPD and asthma exacerbation using EHR. We will investigate the diagnostic accuracy of pneumonia events in people in the general population and among those with COPD or asthma using CPRD Aurum data linked with HES APC, HES A&E, and ONS mortality data. We will validate eligible cases of pneumonia events using data on community acquired pneumonia (CAP) obtained from GP practices for various patient groups using combinations of pneumonia diagnosis code, antibiotics, symptoms, and laboratory results to confirm pneumonia events. We will also look at hospital episode statistics (HES) for patients with and without AECOPD and asthma exacerbations who have evidence of community acquired pneumonia (CAP). To evaluate the accuracy of differentiating pneumonia events from exacerbations, we will calculate sensitivity and specificity and obtain the probability of positive and negative pneumonia diagnosis using CPRD data. We will use PPV and NPV value to compare pneumonia diagnostic accuracy of various clinical features including, symptoms, laboratory investigations and chest X-rays. All calculation for diagnostic test characteristics will be carried out separately for general population, AECOPD and asthma exacerbation.

Health Outcomes to be Measured

COPD exacerbations
Asthma exacerbations


Jennifer Quint - Chief Investigator - Imperial College London
Jennifer Quint - Corresponding Applicant - Imperial College London
Chukwuma Iwundu - Collaborator - Imperial College London
Constantinos Kallis - Collaborator - Imperial College London
Ian Douglas - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )


HES Accident and Emergency;HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation