Context A genetic basis has been identified for many medical
conditions and some molecular tests have been commercialized. However,
little attention has been given to the quality of clinical epidemiology
in molecular studies.
Objective To examine the clinical epidemiological quality of
recent publications on molecular genetic analysis.
Design Cross-sectional study of original research articles
published in 1995, identified by manually searching 4 general clinical
journals. Of 83 articles identified, 40 were selected for analysis;
these 40 discussed molecular genetic techniques, studied 10 or more
patients, and had inferential conclusions.
Main Outcome Measure Compliance of the selected articles with 7
methodological standards for clinical epidemiological science
(reproducibility, objectivity, delineation of case group, adequacy of
spectrum in case group, delineation of comparison group, adequacy of
comparison group, and quantitative summary of results).
Results Among the 40 inferential articles that studied 10 or
more patients, only 5 (12.5%) complied with all 7 applicable
standards, and 10 (25.0%) complied with all but 1 standard, whereas 25
articles (62.5%) failed to comply with 2 or more standards and 9
(22.5%) failed 4 or 5 standards. Most articles did not comply with
standards for reproducibility (n=25, 62.5%) or
objectivity (n=27, 67.5%); however, the majority of
articles did comply with standards for adequacy of case group
(n=35, 87.5%), adequacy of comparison group
(n=35, 87.5%), and quantitative summary of results
Conclusions Despite major laboratory advances in molecular
genetic analysis, our data suggest that reported applications in
clinical journals often have troubling omissions, deficiencies, and
lack of attention to the different, but necessary, principles of
clinical epidemiological science. Without suitable attention to
fundamental methodological standards, the expected benefits of
molecular genetic testing may not be achieved.