# Developing a novel antibiogram tool to improve empiric antibiotic prescribing in nursing homes

> **NIH AHRQ R01** · UNIVERSITY OF WISCONSIN-MADISON · 2020 · $499,482

## Abstract

PROJECT SUMMARY/ABSTRACT
Inappropriate antibiotic use is a common problem that contributes to adverse drug events and antibiotic
resistance in nursing homes (NHs). Empiric antibiotic selection decisions in NHs are frequently suboptimal.
Cumulative susceptibility reports based on patient cultures, known as antibiograms, are tools increasingly being
used to improve empiric antibiotic decisions in NHs. However, most NHs collect an insufficient number of cultures
to permit creation of reliable facility-specific antibiograms causing many facilities to turn to pooled facility
antibiograms. Antibiograms based on combining culture data from multiple facilities improve the reliability of
reported susceptibility estimates and accurately reflect regional antibiotic resistance patterns but may present a
distorted picture of susceptibility patterns at the local level. Consequently, it is possible that increasing use of
pooled facility antibiograms may worsen rather than improve empiric antibiotic decisions in NHs.
The weighted-incidence syndromic combination antibiogram (WISCA) is a novel method that makes better use
of available microbiology data when culture results are scarce. A WISCA also presents data in a manner that
may reduce cognitive load on clinicians. We believe WISCAs will prove to be more reliable than traditional
antibiograms and exert a greater effect on empiric antibiotic decisions in NHs. The objectives of this study are to
develop a user-friendly WISCA tool, compare it to a traditional antibiogram and develop a toolkit for its
implementation and evaluation in NHs. We will achieve these objectives through the following specific aims:
In Aim 1, we will conduct a prospective surveillance study in 82 NHs in four states to characterize antibiotic
susceptibility patterns in NHs using traditional antibiograms and WISCAs. Existing study NH culture data will be
obtained from their reference laboratories. The reliability of the two antibiogram formats will be evaluated and
the congruence between single and pooled facility susceptibility estimates will be estimated.
In Aim 2, we will develop a user-friendly WISCA format with input from NH clinicians. The resulting tool will be
evaluated using a simulated case-study approach in which 300 NH clinicians will be asked to complete several
clinical vignettes describing common NH urinary syndromes. Participants will be randomized to complete the
vignettes using either clinical information alone or with the assistance of a pooled antibiogram or a WISCA tool.
Appropriateness of antibiotic decisions will be compared across the three study arms.
In Aim 3, we will perform a facilitated implementation pilot study in 6-10 NHs in order to develop a toolkit for
implementing and evaluating the WISCA intervention. We will use a mixed-methods approach, structured around
the SEIPS model and Theoretical Domains Framework, to identify implementation barriers and enablers in study
NHs and to identify and design strategies t...

## Key facts

- **NIH application ID:** 10099724
- **Project number:** 1R01HS027820-01
- **Recipient organization:** UNIVERSITY OF WISCONSIN-MADISON
- **Principal Investigator:** Christopher J Crnich
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** AHRQ
- **Fiscal year:** 2020
- **Award amount:** $499,482
- **Award type:** 1
- **Project period:** 2020-09-30 → 2023-09-29

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10099724

## Citation

> US National Institutes of Health, RePORTER application 10099724, Developing a novel antibiogram tool to improve empiric antibiotic prescribing in nursing homes (1R01HS027820-01). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10099724. Licensed CC0.

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