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? Study 2: the Effect of Beta-Adrenoceptor Blocker Therapy on Cancer Survival; a Retrospective Cohort Study

Reference:

David a Springate, Darren M Ashcroft, Evangelos Kontopantelis, Tim Doran, Ronan Ryan, David Reeves(2015) Can analyses of electronic patient records be independently and externally validated? Study 2: the Effect of Beta-Adrenoceptor Blocker Therapy on Cancer Survival; a Retrospective Cohort Study. BMJ Open, doi: 10.1136/bmjopen-2014-007299

Link to fulltext article
Abstract
Objectives To conduct a fully independent and external validation of a research study based on one electronic health record database, using a different database sampling the same population. Design Retrospective cohort analysis of beta-blocker therapy and all-cause mortality in cancer patients. Setting Two UK national primary care databases (PCDs): the Clinical Practice Research Datalink (CPRD) and Doctors’ Independent Network (DIN). Participants CPRD data for 11302 cancer patients compared to published results from DIN for 3462 patients. Study period January 1997 to December 2006. Primary and secondary outcome measures All-cause mortality: overall; by treatment subgroup (betablockers only, beta-blockers plus other blood pressure lowering medicines (BPLM), other BPLMs only); and by cancer-site. Results Using CPRD, beta-blocker use was not associated with mortality (HR=1.03, 95%CI 0.93-1.14, vs patients prescribed other BPLMs only), but in DIN beta-blocker users had significantly higher mortality (HR=1.18, 95%CI 1.04 to 1.33). However, these hazard ratios were not statistically different (p=0.063), but did differ for patients on beta-blockers alone (CPRD=0.94, 95%CI 0.82-1.07; DIN=1.37, 95%CI 1.16-1.61; p<0.001). Results for nine individual cancer sites differed by study, but only significantly for prostate and pancreas cancers. Results were robust under sensitivity analyses, but we could not be certain that mortality was identically defined in both databases. Conclusions We found a complex pattern of similarities and differences between databases. Our finding that overall treatment effect estimates were not statistically different, adds to a growing body of evidence that different UK PCDs produce effect estimates comparable within statistical tolerance. However, some subgroup effects differed significantly and individually the two studies lead to different conclusions regarding the safety of beta-blockers for cancer patients. Single studies based on internally well-validated databases therefore do not guarantee generalisable results, especially for subgroups. In all cases, confirmatory studies using at least one other independent data source are strongly recommended.
Author for correspondence
David Reeves
Email for correspondence
david.reeves@manchester.ac.uk

Code list: res24: lung cancer

24 codes in list

Code Coding system Description Entity type List name
B22..00 Read Malig neop trachea/bronch/lung diagnostic res24: lung cancer
B220.00 Read Malig neop trachea diagnostic res24: lung cancer
B220100 Read Malig neop mucosa of trachea diagnostic res24: lung cancer
B220z00 Read Malig neop trachea NOS diagnostic res24: lung cancer
B221.00 Read Malig neop main bronchus diagnostic res24: lung cancer
B221000 Read Malig neop carina of bronchus diagnostic res24: lung cancer
B221100 Read Malig neop hilus of lung diagnostic res24: lung cancer
B221z00 Read Malig neop main bronchus NOS diagnostic res24: lung cancer
B222.00 Read Malig neop upp lobe bronc/lung diagnostic res24: lung cancer
B222000 Read Malig neop upper lobe bronchus diagnostic res24: lung cancer
B222100 Read Malig neop upper lobe of lung diagnostic res24: lung cancer
B222z00 Read Malig neop upp bronc/lung NOS diagnostic res24: lung cancer
B223.00 Read Malig neop mid lobe bronc/lung diagnostic res24: lung cancer
B223000 Read Malig neop mid lobe bronchus diagnostic res24: lung cancer
B223100 Read Malig neop middle lobe of lung diagnostic res24: lung cancer
B223z00 Read Malig neop mid lobe bronc/lung diagnostic res24: lung cancer
B224.00 Read Malig neop low lobe bronc/lung diagnostic res24: lung cancer
B224000 Read Malig neop lower bronchus diagnostic res24: lung cancer
B224100 Read Malig neop lower lobe of lung diagnostic res24: lung cancer
B224z00 Read Malig neop low lobe bronc/lung diagnostic res24: lung cancer
B225.00 Read Mal neop overlap les bron/lung diagnostic res24: lung cancer
B226.00 Read Mesothelioma diagnostic res24: lung cancer
B22y.00 Read Malig neop oth site bronc/lung diagnostic res24: lung cancer
B22z.00 Read Malig neop bronchus/lung NOS diagnostic res24: lung cancer

0 comments have been posted.

Please log in to leave a comment.