<p>Existing Data Sources in Clinical Epidemiology: Laboratory Information System Databases in Denmark</p>

Abstract

Routine biomarker results from hospital laboratory information systems, covering hospitals and general practitioners, in Denmark are available to researchers through access to the regional Clinical Laboratory Information System Research Database at Aarhus University and the nationwide Register of Laboratory Results for Research. This review describes these two data sources. The laboratory databases have different geographical and temporal coverage. They both include individual-level biomarker results that are electronically transferred from laboratory information systems. The biomarker results can be linked to all other Danish registries at the individual level, using the unique identifier, the CPR number. The databases include variables such as the CPR number, date and time (hour and minute) of sampling, NPU code, and name of the biomarker, identification code for the laboratory and the requisitioner, the test result with the corresponding unit, and the lower and upper reference limits. Access to the two databases differs since they are hosted by two different institutions. Data cannot be transferred outside Denmark, and direct access is provided only to Danish institutions. It is concluded that access to data on routine biomarkers expands the detailed biological and clinical information available on patients in the Danish healthcare system. The full potential is enabled through linkage to other Danish healthcare registries.

Preadmission kidney function and risk of acute kidney injury in patients hospitalized with acute pyelonephritis: A Danish population-based cohort study

“…Multiple imputation of missing values did not change our findings, which was reassuring. Second, the regional LABKA database was fairly complete from 2000 and onwards and The Register of Laboratory Results for Research included an increasing number of hospital throughout the study period [ 18 , 21 ]. However, we do not expect incompleteness to bias our findings because the incompleteness of The Register of Laboratory Results for Research was presumed to be independent of both preadmission kidney function and the risk of AKI.…”

“…All Danish citizens have a unique 10-digit civil registration number, which is assigned at birth or immigration, including information on sex and date of birth [ 15 – 17 ]. This number facilitates linkage of individual-level data between Danish databases including laboratory databases, The Danish Civil Registration System, The Danish National Patient Registry, and The Danish National Prescription Registry [ 14 – 16 , 18 – 21 ]. The Danish health care system is tax-funded and therefore all Danish citizens have free access to medical care at public hospitals.…”

Existing Data Sources in Clinical Epidemiology: The Taiwan National Health Insurance Laboratory Databases

“…The overall pattern is similar to that in other countries; nevertheless, the exact ranking of the particular laboratory tests might be different due to the differences in disease prevalence and prescription behaviors across countries. [19][20][21][22][23][24] The five most commonly performed tests in Taiwan were whole blood count (including the hemoglobin and white blood count), urine routine, white blood cell differential count, blood sugar, and blood creatinine. When considering the number of persons, the leading five tests were blood creatinine, glutamate pyruvate transaminase or alanine transaminase (GPT/ALT), blood sugar, glutamic-oxaloacetic transaminase or aspartate aminotransferase (GOT/AST), and potassium.…”

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“…individual-level data between Danish databases including laboratory databases, The Danish Civil Registration System, The Danish National Patient Registry, and The Danish National Prescription Registry [14][15][16][18][19][20][21]. The Danish health care system is tax-funded and therefore all Danish citizens have free access to medical care at public hospitals.…”

“…eGFR was further categorized into <30, 30-44, 45-59, 60-89, and �90 corresponding to the eGFR categorization of chronic kidney disease from Kidney Disease Improving Global Outcomes (KDIGO) [26]. Data on sCr were retrieved from the Register of Laboratory Results for Research [21], which contains collected results from inpatients, outpatients, and visitors at the general practitioners from all regions of Denmark except from the Central Denmark region from where we retrieved information from the regional clinical laboratory information system (LABKA) database [18]. The laboratory databases are increasingly complete throughout the study period, but unfortunately, not all regions of Denmark are covered throughout the study period.…”