Registration of acute medical hospital admissions in the Danish National Patient Registry: a validation study

Abstract

Background

In recent years, the number of acute hospital admissions has increased and this has imposed both organizational and financial strains on the health care system. Consequently, it is of crucial importance that we have valid data on admission types in the administrative databases in order to provide data for health care planning and research.

Objective

To examine the validity of registration of acute admissions among medical patients in the Danish National Patient Registry (DNPR) using medical record reviews as the reference standard.

Methods

We used the nationwide DNPR to identify a sample of 160 medical patients admitted to a hospital in the North Denmark Region during 2009. Data on admission type was obtained from the DNPR and confirmed by a medical record review. We computed positive predictive values, sensitivity, and specificity including 95% confidence intervals (CI) using the medical record review as the reference standard.

Results

Among the 160 medical inpatients identified in the DNPR, 128 were registered with an acute admission, and 32 were registered with a nonacute admission. Two medical records could not be located. Thus, the analyses included 158 medical patients. Among the 127 patients registered with acute admission, 124 were confirmed to be correctly classified. Correspondingly, 28 of the 31 patients with a registered nonacute admission were confirmed to be correctly classified. The overall positive predictive value of the acute admissions among medical patients was 97.6% (95% CI, 93.8%–99.3%). Sensitivity was 97.6% (95% CI, 93.8%–99.3%) and specificity was 90.3% (95% CI, 76.4%–97.2%).

Conclusion

The registration of acute admission among medical patients in the DNPR has high validity.

Keywords:

• medical patients
• registries
• epidemiology
• positive predictive value
• sensitivity
• specificity

Acknowledgments

This study was made possible with the invaluable help from the secretaries at the medical departments. Especially, we would like to thank Elisabeth V Kristoffersen for her help with retrieving and organizing the medical records.

Financial support: The study was supported by the Clinical Epidemiological Research Foundation, Denmark, and Aarhus University.

Disclosure

The authors report no conflicts of interest in this work.