ClinicalCodes.org

An online clinical codes repository to improve validity and reproducibility of medical database research

Research article:

Can analyses of electronic patient records be independently and externally validated? The effect of statins on the mortality of patients with Ischaemic heart disease: a cohort study with nested case-control analysis

Reference:

David Reeves, David Springate, Darren M Ashcroft, Ronan Ryan, Tim Doran, Richard Morris, Ivan Olier, Evangelos Kontopantelis(2014) Can analyses of electronic patient records be independently and externally validated? The effect of statins on the mortality of patients with Ischaemic heart disease: a cohort study with nested case-control analysis. BMJ Open, doi: doi:10.1136/bmjopen-2014-004952

Link to fulltext article
Abstract
Objective To conduct a fully independent and external validation of a research study based on one electronic health records database, using a different electronic database sampling the same population. Design Using the Clinical Practice Research Datalink (CPRD), we replicated a published investigation into the effects of statins in patients with ischaemic heart disease (IHD) by a different research team using QResearch. We replicated the original methods and analysed all cause mortality using: (i) a cohort analysis and (ii) a case-control analysis nested within the full cohort. Setting Electronic health record databases containing longitudinal patient consultation data from large numbers of general practices distributed throughout the UK. Participants CPRD data for 34925 patients with IHD from 224 general practices, compared against previously published results from QResearch for 13,029 patients from 89 general practices. The study period was January 1996 to December 2003. Results We successfully replicated the methods of the original study very closely. In cohort analysis risk of death was lower by 55% for patients on statins, compared to 53% for QResearch (adjusted HR 0.45, 95% CI 0.40 to 0.50; versus 0.47, 95% CI 0.41 to 0.53). In case-control analyses patients on statins had a 31% lower odds of death, compared to 39% for QResearch (adjusted OR 0.69, 95% CI 0.63 to 0.75; versus OR 0.61, 95% CI 0.52 to 0.72). Results were also close for individual statins. Conclusion Database differences in population characteristics and in data definitions, recording, quality and completeness had minimal impact on key statistical outputs. The results uphold the validity of research using CPRD and QResearch, by providing independent evidence that both datasets produce very similar estimates of treatment effect, leading to the same clinical and policy decisions. Together with other, non-independent, replication studies there is a nascent body of evidence for wider validity.
Author for correspondence
David Reeves
Email for correspondence
david.reeves@manchester.ac.uk

Code list: Congestive cardiac failure

27 codes in list

Code Coding system Description Entity type List name
G1yz100 Read Rheumatic left ventricular failure diagnostic Congestive cardiac failure
G58..00 Read Heart failure diagnostic Congestive cardiac failure
G580.00 Read Congestive heart failure diagnostic Congestive cardiac failure
G580000 Read Acute congestive heart failure diagnostic Congestive cardiac failure
G580100 Read Chronic congestive heart failure diagnostic Congestive cardiac failure
G580.11 Read Congestive cardiac failure diagnostic Congestive cardiac failure
G580.12 Read Right heart failure diagnostic Congestive cardiac failure
G580.13 Read Right ventricular failure diagnostic Congestive cardiac failure
G580.14 Read Biventricular failure diagnostic Congestive cardiac failure
G580200 Read Decompensated cardiac failure diagnostic Congestive cardiac failure
G580300 Read Compensated cardiac failure diagnostic Congestive cardiac failure
G580400 Read Congestive heart failure due to valvular disease diagnostic Congestive cardiac failure
G581.00 Read Left ventricular failure diagnostic Congestive cardiac failure
G581000 Read Acute left ventricular failure diagnostic Congestive cardiac failure
G58..11 Read Cardiac failure diagnostic Congestive cardiac failure
G581.11 Read Asthma - cardiac diagnostic Congestive cardiac failure
G581.12 Read Pulmonary oedema - acute diagnostic Congestive cardiac failure
G581.13 Read Impaired left ventricular function diagnostic Congestive cardiac failure
G582.00 Read Acute heart failure diagnostic Congestive cardiac failure
G583.00 Read Heart failure with normal ejection fraction diagnostic Congestive cardiac failure
G583.11 Read HFNEF - heart failure with normal ejection fraction diagnostic Congestive cardiac failure
G584.00 Read diagnostic Congestive cardiac failure
G58z.00 Read Heart failure NOS diagnostic Congestive cardiac failure
G58z.11 Read Weak heart diagnostic Congestive cardiac failure
G58z.12 Read Cardiac failure NOS diagnostic Congestive cardiac failure
G5yy900 Read Left ventricular systolic dysfunction diagnostic Congestive cardiac failure
G5yyA00 Read Left ventricular diastolic dysfunction diagnostic Congestive cardiac failure

0 comments have been posted.

Please log in to leave a comment.

Quick links:

Code list links:

Only the original uploading author or an administrator can add, edit or delete this article and its associated codes.

University of Manchester IPH ClinicalCodes is a project at the University of Manchester Institute of Population Health

Funded by NIHR School for Primary Care The ClinicalCodes project is funded by the National Institute for Health Research (NIHR) School for Primary Care Research (SPCR)

© 2013-2014 University of Manchester all rights reserved