Automatic identification of variables in epidemiological datasets using logic regression

BMC Med Inform Decis Mak. 2017 Apr 13;17(1):40. doi: 10.1186/s12911-017-0429-1.


Background: For an individual participant data (IPD) meta-analysis, multiple datasets must be transformed in a consistent format, e.g. using uniform variable names. When large numbers of datasets have to be processed, this can be a time-consuming and error-prone task. Automated or semi-automated identification of variables can help to reduce the workload and improve the data quality. For semi-automation high sensitivity in the recognition of matching variables is particularly important, because it allows creating software which for a target variable presents a choice of source variables, from which a user can choose the matching one, with only low risk of having missed a correct source variable.

Methods: For each variable in a set of target variables, a number of simple rules were manually created. With logic regression, an optimal Boolean combination of these rules was searched for every target variable, using a random subset of a large database of epidemiological and clinical cohort data (construction subset). In a second subset of this database (validation subset), this optimal combination rules were validated.

Results: In the construction sample, 41 target variables were allocated on average with a positive predictive value (PPV) of 34%, and a negative predictive value (NPV) of 95%. In the validation sample, PPV was 33%, whereas NPV remained at 94%. In the construction sample, PPV was 50% or less in 63% of all variables, in the validation sample in 71% of all variables.

Conclusions: We demonstrated that the application of logic regression in a complex data management task in large epidemiological IPD meta-analyses is feasible. However, the performance of the algorithm is poor, which may require backup strategies.

Keywords: Data management; Epidemiology; Logic regression; Meta-analysis.

MeSH terms

  • Algorithms
  • Carotid Artery Diseases / diagnostic imaging*
  • Carotid Intima-Media Thickness
  • Data Mining
  • Databases, Factual*
  • Epidemiologic Factors*
  • Humans
  • Logistic Models*
  • Medical Informatics Applications*
  • Meta-Analysis as Topic
  • Predictive Value of Tests
  • Prognosis