Development, validation and evaluation of an electronic pharmacological tool: The Drug Burden Index Calculator©

The Drug Burden Index (DBI) is a pharmacological risk assessment tool that measures the total exposure to anticholinergic and sedative medicines, which may impair function in older adults. A computerized clinical decision support system (CCDSS) for DBI has not been previously developed or evaluated.

(a) Develop a CCDSS that calculates and generates reports on DBI; (b) validate the CCDSS for accuracy; and (c) evaluate the CCDSS for use in clinical practice.

The DBI Calculator© application, based on the published formula and Australian registered prescribing information was built and designed using Microsoft Access 2010. Accuracy testing involved the comparison of DBI scores computed manually (gold standard) with those computed using The DBI Calculator© for 25 published medication review case studies. Agreement was measured using Cohen's Kappa statistic. To evaluate the CCDSS application in practice, ten pharmacists completed a performance test and usability survey. Participants were timed performing a DBI calculation with the application for a fictitious patient case. The interface, functionality, clinical applications and user satisfaction of the application were rated using 5-point, Likert-type scales.

Excellent agreement between the manual and CCDSS application was observed (Cohen's Kappa 0.95). In the evaluation phase, the average time (mins:sec ± SD) for participants to complete the task was 7:20 ± 1:45 and the DBI Calculator© was considered useful by 80% of pharmacists for recognizing sedative and anticholinergic medicines in practice.

A reliable CCDSS has been developed to report DBI of older patients taking multiple medications. Future studies should test the utility of The DBI Calculator© in clinical practice.