Skip to main content
Open Forum Infectious Diseases logoLink to Open Forum Infectious Diseases
. 2023 Nov 21;10(12):ofad585. doi: 10.1093/ofid/ofad585

Evaluation of Multisite Programmatic Bundle to Reduce Unnecessary Antibiotic Prescribing for Respiratory Infections: A Retrospective Cohort Study

Dan Ilges 1, Kelsey Jensen 2, Evan Draper 3, Ross Dierkhising 4, Kimberly A Prigge 5, Paschalis Vergidis 6, Abinash Virk 7, Ryan W Stevens 8,1,✉,3
PMCID: PMC10727194  PMID: 38111752

Abstract

Background

The aim of this study was to evaluate the frequency of unnecessary antibiotic prescribing for Tier 3 upper respiratory infection (URI) syndromes across the Mayo Clinic Enterprise before and after a multifaceted antimicrobial stewardship intervention, and to determine ongoing factors associated with antibiotic prescribing and repeat respiratory healthcare contact in the postintervention period.

Methods

This was a quasi-experimental, pre/post, retrospective cohort study from 1 January 2019 through 31 December 2022, with 12-month washout during implementation from 1 July 2020 through 30 June 2021. All outpatient encounters, adult and pediatric, from primary care, urgent care, and emergency medicine specialties with a Tier 3 URI diagnosis were included. The intervention was a multifaceted outpatient antibiotic stewardship bundle. The primary outcome was the rate of antibiotic prescribing in Tier 3 encounters. Secondary outcomes included 14-day repeat healthcare contact for respiratory indications and factors associated with persistent unnecessary prescribing.

Results

A total of 165 658 Tier 3 encounters, 96 125 in the preintervention and 69 533 in the postintervention period, were included. Following intervention, the prescribing rate for Tier 3 encounters decreased from 21.7% to 11.2% (P < .001). Repeat 14-day respiratory healthcare contact in the no antibiotic group was lower postintervention (9.9.% vs 9.4%; P = .004). Multivariable models indicated that increasing patient age, Charlson comorbidity index, and primary diagnosis selected were the most important factors associated with persistent unnecessary antibiotic prescribing.

Conclusions

Outpatient antibiotic stewardship initiatives can reduce unnecessary antibiotic prescribing for Tier 3 URIs without increasing repeat respiratory healthcare contact. Advancing age and number of comorbidities remain risk factors for persistent unnecessary antibiotic prescribing.


Approximately 80%–90% of all antimicrobial consumption occurs in outpatient settings [1]; however, up to 50% of these prescriptions may be inappropriate, with roughly 1 in 3 completely unnecessary [1–4]. Indiscriminate antibiotic prescribing is associated with harm to both individual patients (eg, adverse effects, such as diarrhea, rash, and photosensitivity) [5] and the broader population (eg, antimicrobial resistance and increased healthcare costs) [6]. In 2016, the Centers for Disease Control and Prevention published the Core Elements of Outpatient Antibiotic Stewardship, which encourages outpatient antimicrobial stewardship programs (ASP) to identify 1 or more high-priority targets [7].

Upper respiratory infections (URIs) represent the most common indication for outpatient antibiotic prescribing; however, a majority of URIs are viral in etiology [8]. For example, despite guidelines recommending against antibiotic therapy for most patients with acute uncomplicated bronchitis, studies indicate that antibiotics may be prescribed in as many as 70%–85% of outpatient bronchitis encounters [9, 10]. Even for viral URIs with a known etiology, antibiotic prescribing remains an issue, with 1 study noting a prescribing rate of 29% in patients positive for influenza without findings of pneumonia [11].

Numerous antimicrobial stewardship interventions have been effective in reducing unnecessary URI-related antibiotic prescribing [12]. Examples of interventions include peer comparison reports, provider education, patient education, order preference list modifications, antibiotic commitment posters, viral prescription pads, and electronic order sets [13–16]. Although the literature supports outpatient antibiotic stewardship practices, few studies evaluate (1) the durability of intervention(s), (2) the impact of intervention(s) across various geographic sites, (3) control outcomes (eg, rates of repeat healthcare contact for URI with and without antibiotic prescriptions), and (4) factors associated with ongoing, unnecessary/inappropriate antibiotic prescribing following initial intervention.

We aim to evaluate the frequency of unnecessary antibiotic prescribing for URI and the rate of repeat respiratory-related healthcare contact before and after a multifaceted, health system–wide antimicrobial stewardship initiative. Furthermore, we aim to determine patient, provider, and encounter-level factors associated with continued unnecessary antibiotic prescribing in the postimplementation period.

METHODS

Patient Consent Statement

Patient consent was not required as this retrospective cohort study was deemed exempt by the Mayo Clinic institutional review board (IRB number 23–001010) and was reported following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline for cohort studies.

Study Design, Setting, and Interventions

This quasi-experimental, pre/post retrospective cohort study spanned 1 January 2019 to 31 December 2022. Starting 1 January 2020, Mayo Clinic implemented a comprehensive, Enterprise-wide outpatient ASP aimed at reducing unnecessary antibiotic prescribing for URIs not expected to benefit from antibiotic therapy. The Mayo Clinic Enterprise consists of 3 major destination medical centers in Rochester (Minnesota), Arizona, and Florida, along with the Mayo Clinic Health System, a network of hospitals and clinics throughout 4 regions in Minnesota and Wisconsin (southwest Wisconsin, northwest Wisconsin, southeast Minnesota, and southwest Minnesota). The initiative targeted 3 ambulatory care specialties, including primary care (ie, family medicine, community-internal medicine, women's health internal medicine, and community pediatrics and adolescent medicine), urgent care, and emergency medicine.

A multifaceted bundle of programmatic ASP interventions was implemented across the Enterprise in a stepwise fashion beginning 1 July 2020. Specific interventions included standardized provider education, dissemination of patient handouts promoting symptomatic management (ie, Viral Rx pad [17]), development of a syndrome-based, prepopulated ambulatory order panel (ie, clinical decision support tool, see Supplementary Materials), a patient-facing antibiotic commitment poster, peer comparison reporting, and a provider-facing data dashboard to facilitate self-auditing of cases where prescribing was flagged as unnecessary [17, 18]. Regional efforts were administered by local ASPs, consisting of at least 1 pharmacist and/or 1 physician trained in infectious diseases and antimicrobial stewardship.

Participants, Data Collection, and Outcomes

Respiratory International Classification of Diseases, 10th Revision (ICD-10) diagnosis codes were grouped into tiers according to whether antibiotics are always indicated (Tier 1), sometimes indicated (Tier 2), or never indicated (Tier 3) as previously described (see Supplementary Materials) [8, 17]. Given lack of standardization across the full dataset and concerns for skewing of the data, coronavirus disease 2019 (COVID-19)–related diagnosis codes were excluded. All ambulatory encounters, including both in-person and virtual, with Tier 3 primary diagnosis codes from primary care, emergency medicine, and urgent care departments were eligible for inclusion. Minnesota patients required documentation of the Minnesota Research Authorization. Encounters with secondary diagnoses that included Tier 1 or Tier 2 URI codes were excluded. For patients with multiple encounters, each unique encounter was included if inclusion criteria were met.

Data were extracted from an electronic health record database and an institutional data warehouse. Data elements included encounter (eg, region, encounter type, encounter date, and ICD-10 billing code), patient (eg, age, sex, race/ethnicity, antibiotic prescription, Charlson comorbidity index [CCI] [19], respiratory comorbidities), and provider features (eg, provider type, department), as well as encounter season. Patient demographic data were self-identified and included to ascertain the influence these characteristics on prescribing patterns and overall healthcare utilization. Monthly encounter volumes were determined in the postimplementation cohort to assess the impact of overall encounter volumes (ie, clinic workload) on unnecessary antibiotic prescribing. Monthly encounter volumes for all clinic encounters (including nonrespiratory encounters) were averaged for each specific clinic during the postimplementation period to determine a baseline or “expected” number of total monthly encounters. Monthly clinic encounter volumes were then compared to this baseline and converted to ordinal values of low (>1 standard deviation [SD] below mean), mild (between 0 and 1 SD below mean), moderate (between 0 and 1 SD above mean), and high (>1 SD above mean) volume for each month. Thus, high clinic volume months indicate busier months, whereas low clinic volume months indicate less busy months.

The primary outcome was the percentage of Tier 3 encounters that resulted in an antibiotic prescription. Secondary outcomes included the rate of repeat respiratory-related healthcare contact (ie, hospitalization, clinic visits, and emergency encounters) within 14 days of the index visit and patient, provider, and encounter-level factors associated with unnecessary prescribing or repeat respiratory-related healthcare contact after implementation of the intervention bundle.

Statistical Analysis

Study periods were defined as preimplementation (1 January 2019–30 June 2020), implementation/washout (1 July 2020–30 June 2021), and postimplementation (1 July 2021–31 December 2022).

Means and standard errors are presented for continuous variables and frequencies, and percentages are presented for categorical variables. Pearson χ2 test was used to compare pre- and postintervention periods for antibiotic prescription and 14-day repeat respiratory-related healthcare contact. These comparisons were done for the overall sample and within a priori–specified patient, provider, and encounter-level subgroups.

Univariate and multivariable logistic regression models were fit in the postimplementation cohort to identify patient, provider, and encounter-level factors associated with both antibiotic prescribing and with 14-day repeat healthcare contact for respiratory indications. Gradient boosting machine models were used to estimate the relative influence of individual variables to identify smaller models that retained most of the predictive ability. A complete-case analysis was done in the case of missing data. R statistical software version 4.1 was utilized for all analysis (R Foundation for Statistical Computing, Vienna, Austria). Statistical significance was defined as P < .05.

RESULTS

There was a total of 511 196 respiratory encounters across the Mayo Clinic Enterprise between 1 January 2019 and 31 December 2022. Of these, 184 417 Tier 3 encounters were eligible for inclusion, including 96 125, 18 759, and 69 533 in the preintervention, implementation/washout, and postintervention periods, respectively (Figure 1).

Figure 1.

Figure 1.

A, Total number of Tier 3 (never prescribe) ambulatory encounters over time by quarter across intervention periods. B, Tier 3 encounter antibiotic prescribing rate over time by quarter across intervention periods.

Baseline characteristics were similar between pre- and postintervention periods (Table 1). Approximately 45% of encounters were patients aged ≤18 years, with 20% of overall encounters among patients aged between 0 and 2 years. Most patients (89.4%) identified as White, while just over half were female (56.1%). Overall, 15.6% of all encounters included patients with at least 1 significant preexisting respiratory condition (ie, asthma, cystic fibrosis, pulmonary fibrosis, and bronchiectasis). Most encounters (68.8%) occurred between October and March. Primary care settings accounted for most visits (45.8%), while urgent care and emergency medicine accounted for 29.4% and 24.8% of overall encounters, respectively. Telehealth visits were more frequent in the post- compared to the preintervention period at 8.1% versus 3.5%, respectively.

Table 1.

Baseline Characteristics Among Encounters in the Pre- and Postintervention Periods

Characteristic Preintervention (n = 96 125) Postintervention (n = 69 533) Total (n = 165 658)
Age, mean (std error) 30.52 (0.08) 26.99 (0.10) 29.04 (0.06)
Age group, y
 0–2 17 824 (18.5) 15 368 (22.1) 33 192 (20.0)
 3–18 22 674 (23.6) 18 764 (27.0) 41 438 (25.0)
 19–65 43 876 (45.6) 27 743 (39.9) 71 619 (43.2)
 >65 11 751 (12.2) 7658 (11.0) 19 409 (11.7)
Sexa
 Female 54 226 (56.4) 38 771 (55.8) 92 997 (56.1)
 Male 41 886 (43.6) 30 756 (44.2) 72 642 (43.9)
 Nonbinary 5 (0.0) 4 (0.0) 9 (0.0)
Raceb
 American Indian/Alaska Native 416 (0.4) 376 (0.5) 792 (0.5)
 Asian 2496 (2.6) 1922 (2.8) 4418 (2.7)
 Black or African American 4391 (4.6) 3696 (5.4) 8087 (5.0)
 Native Hawaiian/Pacific Islander 188 (0.2) 186 (0.3) 374 (0.2)
 Other 2329 (2.5) 1265 (1.8) 3594 (2.2)
 White 84 847 (89.6) 60 979 (89.1) 145 826 (89.4)
Encounter Season
 Apr–Sep 26 576 (27.6) 25 160 (36.2) 51 736 (31.2)
 Oct–Mar 69 549 (72.4) 44 373 (63.8) 113 922 (68.8)
Pulmonary comorbidities
 Any 17 678 (18.4) 8216 (11.8) 25 894 (15.6)
 Asthma 15 971 (16.6) 6999 (10.1) 22 970 (13.9)
 Cystic fibrosis 40 (0.0) 31 (0.0) 71 (0.0)
 Pulmonary fibrosis 2236 (2.3) 1273 (1.8) 3509 (2.1)
 Bronchiectasis 678 (0.7) 484 (0.7) 1162 (0.7)
Provider type
 APP 51 453 (53.5) 38 570 (55.5) 90 023 (54.3)
 Physician 44 003 (45.8) 28 813 (41.4) 72 816 (44.0)
 Trainee 669 (0.7) 2150 (3.1) 2819 (1.7)
Region
 Arizona 4622 (4.8) 2843 (4.1) 7465 (4.5)
 Florida 5817 (6.1) 3842 (5.5) 9659 (5.8)
 MCHS NW WI 17 652 (18.4) 12 143 (17.5) 29 795 (18.0)
 MCHS SE MN 21 539 (22.4) 16 332 (23.5) 37 871 (22.9)
 MCHS SW MN 15 981 (16.6) 12 019 (17.3) 28 000 (16.9)
 MCHS SW WI 10 246 (10.7) 7283 (10.5) 17 529 (10.6)
 Rochester, MN 20 268 (21.1) 15 071 (21.7) 35 339 (21.3)
Department specialty
 Primary care 44 395 (46.2) 31 472 (45.3) 75 867 (45.8)
 Urgent care 31 372 (32.6) 17 370 (25.0) 48 742 (29.4)
 Emergency medicine 20 358 (21.2) 20 691 (29.8) 41 049 (24.8)
Telehealth visit 3401 (3.5) 5655 (8.1) 9056 (5.5)
Primary diagnosis
 Bronchitis/bronchiolitis 15 429 (16.1) 8354 (12.0) 23 783 (14.4)
 Influenza 10 950 (11.4) 6048 (8.7) 16 998 (10.3)
 Laryngitis/pharyngitis 2716 (2.8) 2747 (4.0) 5463 (3.3)
 Other 61 (0.1) 69 (0.1) 130 (0.1)
 Rhinitis 6527 (6.8) 5503 (7.9) 12 030 (7.3)
 Serous AOM/ear disorders 8349 (8.7) 6122 (8.8) 14 471 (8.7)
 URI unspecified 52 093 (54.2) 40 690 (58.5) 92 783 (56.0)
Total monthly clinic encounter volume
 Low 8338 (12.0) 8338 (12.0)
 Mild 19 779 (28.4) 19 779 (28.4)
 Moderate 24 489 (35.2) 24 489 (35.2)
 High 16 927 (24.3) 16 927 (24.3)
Afternoon encounterc 52 606 (55.8) 39 174 (57.2) 91 780 (56.4)
CCI score, mean (std error) 1.22 (0.01) 1.06 (0.01) 1.15 (0.01)
 0 51 071 (53.1) 41 456 (59.6) 92 527 (55.9)
 1–2 30 936 (32.2) 19 145 (27.5) 50 081 (30.2)
 3–4 6880 (7.2) 4301 (6.2) 11 181 (6.7)
 ≥5 7238 (7.5) 4631 (6.7) 11 869 (7.2)

Results are shown as No. (%) unless otherwise specified.

Abbreviations: APP, advanced practice provider; CCI, Charlson comorbidity index; MCHS, Mayo Clinic Health System; MN, Minnesota; NW, northwest; AOM, acute otitis media; SE, southeast; SW, southwest; URI, upper respiratory infection; WI, Wisconsin.

a10 missing values (8 pre and 2 post).

b2567 missing values (1458 pre and 1109 post).

c3000 missing values (1903 pre and 1097 post).

Antibiotic Prescribing

Antibiotic prescribing for Tier 3 indications decreased from 21.7% in the preintervention period to 11.2% in the postintervention period (P < .001; Table 2, Figure 1). Significant reductions in prescribing were observed among all geographic regions and departments (P < .001 for all comparisons), with the largest improvement noted among urgent care clinics (51.8% relative reduction, from 24.5% to 11.8%). Rates of specific antibiotics prescribed in each period are supplied in Supplementary Table 1. Overall, the relative frequency of specific antibiotic prescriptions shifted following the intervention, with azithromycin accounting for a lower percentage of all antibiotic prescriptions in the postimplementation period (47.1% preimplementation vs 30.4% postimplementation), whereas β-lactam prescription frequency increased.

Table 2.

Antibiotic Prescribing Among Tier 3 Respiratory Encounters in the Pre- and Postintervention Periods, Overall and by Subgroup

Antibiotic Prescribing Preintervention (n = 96 125) Postintervention (n = 69 533) P Value
Overall 20 846 (21.7) 7776 (11.2) <.001
Region
 Arizona 1241/4622 (26.8) 525/2843 (18.5) <.001
 Florida 2199/5817 (37.8) 477/3842 (12.4) <.001
 MCHS NW WI 4073/17 652 (23.1) 1750/12 143 (14.4) <.001
 MCHS SE MN 6023/21 539 (28.0) 2544/16 332 (15.6) <.001
 MCHS SW MN 3841/15 981 (24.0) 848/12 019 (7.1) <.001
 MCHS SW WI 2012/10 246 (19.6) 716/7283 (9.8) <.001
 Rochester, MN 1457/20 269 (7.2) 916/15 071 (6.1) <.001
Department specialty
 Primary care 10 119/44 395 (22.8) 3917/31 472 (12.4) <.001
 Urgent care 7673/31 372 (24.5) 2049/17 370 (11.8) <.001
 Emergency medicine 3054/20 358 (15.0) 1810/20 691 (8.7) <.001
Encounter type
 In-person 20 579/92 724 (22.2) 7591/63 878 (11.4) <.001
 Telehealth 267/3401 (7.9) 485/5655 (8.6) .225
Provider type
 APP 11 436/51 453 (22.2 4374/38 570 (11.3) <.001
 Physician 9316/44 003 (21.2) 3144/28 813 (10.9) <.001
 Trainee 94/669 (14.1) 258/2150 (12.0) .161
Age group, y
 0–2 2414/17 824 (13.5) 1368/15 368 (8.9) <.001
 3–18 3736/22 674 (16.5) 1699/18 764 (9.1) <.001
 19–65 10 645/43 876 (24.3) 3353/27 743 (12.1) <.001
 >65 4051/11 751 (34.5) 1356/7658 (17.7) <.001
Primary diagnosis
 Bronchitis/bronchiolitis 8509/15 429 (55.1) 2350/8354 (28.1) <.001
 Influenza 502/10 950 (4.6) 148/6048 (2.4) <.001
 Laryngitis/pharyngitis 122/2716 (4.5) 89/2747 (3.2) .016
 Other 11/61 (18.0) 11/69 (15.9) .751
 Rhinitis 366/6527 (5.6) 183/5503 (3.3) <.001
 Serous AOM/ear disorders 4548/8349 (54.5) 2578/6122 (42.1) <.001
 URI unspecified 6788/52 093 (13.0) 2417/40 690 (5.9) <.001
CCI score
 0 7668/51 071 (15.0) 3638/41 456 (8.8) <.001
 1–2 8499/30 936 (27.5) 2549/19 145 (13.3) <.001
 3–4 2209/6880 (32.1) 737/4301 (17.1) <.001
 ≥5 2470/7238 (34.1) 852/4631 (18.4) <.001

Results are shown as No. (%) unless otherwise specified.

Abbreviations: APP, advanced practice provider; CCI, Charlson comorbidity index; MCHS, Mayo Clinic Health System; MN, Minnesota; NW, northwest; AOM, acute otitis media; SE, southeast; SW, southwest; URI, upper respiratory infection; WI, Wisconsin.

Repeat Respiratory-Related Healthcare Contact

Repeat healthcare contact for respiratory conditions within 14 days of index encounter was less common when an antibiotic was prescribed in the overall cohort (6.9% antibiotics vs 9.7% no antibiotic, P < .001; Supplementary Table 2). This finding was consistent in both the pre- and postintervention cohorts. The rate of repeat respiratory-related healthcare contact in those receiving antibiotic prescriptions was numerically higher but not significantly different in the postintervention compared to the preintervention cohort (6.7% pre vs 7.3% post, P = .116). Repeat respiratory-related healthcare contact was less common in the postimplementation cohort among encounters where an antibiotic was not prescribed (9.9% preintervention vs 9.4% postintervention, P = .004).

Predictors of Antibiotic Prescribing in the Postimplementation Cohort

In the univariate model (Supplementary Table 3), increasing patient age and CCI were strongly associated with increased likelihood of antibiotic prescribing (age >65: odds ratio [OR], 2.20 [95% confidence interval {CI}, 2.03–2.39]; CCI ≥5: OR, 2.34 [95% CI, 2.16–2.54]; P < .001 for both comparisons). All concomitant respiratory conditions, excluding cystic fibrosis, were associated with antibiotic prescribing. Interestingly, higher total monthly clinic encounter volumes were associated with lower antibiotic prescribing (OR, 0.67 [95% CI, .62–.73]; P < .001). Relative to bronchitis/bronchiolitis, serous acute otitis media (AOM)/ear disorders had a higher rate of antibiotic prescribing (OR, 1.86 [95% CI, 1.73–1.99]; P < .001), whereas influenza, laryngitis/pharyngitis, rhinitis, and unspecified URI were associated with lower prescribing rates.

In the multivariable model, advancing age, increasing CCI, and serous acute otitis media (AOM)/ear disorders were associated with antibiotic prescribing, whereas high total monthly clinic encounter volume was associated with less antibiotic prescribing (Table 3). No difference was noted among provider type. Afternoon encounters were marginally associated with antibiotic prescribing (OR, 1.06 [95% CI, 1.01–1.12]; P = .027). Males were more likely to receive an antibiotic prescription compared to females in the overall model (OR, 1.08 [95% CI, 1.02–1.14]; P = .007). Patients identifying as Asian, Black or African American, or other race were slightly less likely to receive antibiotic prescriptions relative to White patients. The top 3 variables influencing antibiotic prescribing included the primary diagnosis (ie, syndrome) from index encounter, patient age, and CCI, which accounted for >95% of relative influence (Supplementary Figure 1), suggesting that persistent prescribing can be largely predicted by these 3 factors. This is also supported by the closeness of the area under the receiver operating characteristic (ROC) curves from the 2-multivariable models (0.799 for the full model vs 0.795 for the 3-variable model).

Table 3.

Multivariable Models for Antibiotic Prescriptions in the Postintervention Cohort

Characteristic All Variables (n = 67 341) Top 3 (n = 69 533)
OR (95% CI) P Value OR (95% CI) P Value
Age group, y
 0–2
 3–18 1.28 (1.18–1.40) <.001 1.25 (1.15–1.36) <.001
 19–65 1.51 (1.39–1.64) <.001 1.43 (1.32–1.56) <.001
 >65 1.90 (1.70–2.13) <.001 1.93 (1.73–2.15) <.001
Male sex 1.08 (1.02–1.14) .007
Race
 White
 American Indian/Alaska Native 0.75 (.50–1.10) .2
 Asian 0.81 (.67–.97) .027
 Black or African American 0.84 (.73–.96) .012
 Native Hawaiian/Pacific Islander 0.87 (.48–1.47) .6
 Other 0.74 (.58–.94) .015
Encounter season
 Apr–Sep
 Oct–Mar 1.06 (1.00–1.12) .033
Asthma 0.95 (.87–1.04) .3
Cystic fibrosis 1.95 (.54–5.38) .2
Pulmonary fibrosis 1.08 (.91–1.28) .4
Bronchiectasis 1.57 (1.22–2.01) <.001
Provider type
 APP
 Physician 1.06 (1.0–1.12) .074
 Trainee 1.12 (.96–1.29) .15
Department specialty
 Primary care
 Urgent care 0.86 (.80–.92) <.001
 Emergency medicine 0.95 (.88–1.02) .13
Telehealth visit 1.07 (.96–1.19) .2
Primary diagnosis
 Bronchitis/bronchiolitis
 Influenza 0.07 (.06–.08) <.001 0.07 (.06–.08) <.001
 Laryngitis/pharyngitis 0.11 (.09–.14) <.001 0.11 (.09–.14) <.001
 Other 0.47 (.23–.87) .025 0.47 (.23–.88) .026
 Rhinitis 0.08 (.07–.09) <.001 0.08 (.07–.09) <.001
 Serous AOM/ear disorders 2.27 (2.10–2.46) <.001 2.23 (2.07–2.40) <.001
 URI unspecified 0.18 (.17–.20) <.001 0.18 (.17–.19) <.001
Total monthly clinic encounter volume
 Low
 Mild 0.95 (.88–1.04) .3
 Moderate 0.93 (.85–1.01) .082
 High 0.76 (.69–.83) <.001
Encounter time
 Morning
 Afternoon 1.06 (1.01–1.12) .027
CCI score
 0
 1–2 1.38 (1.29–1.49) <.001 1.39 (1.30–1.48) <.001
 3–4 1.71 (1.53–1.91) <.001 1.75 (1.57–1.94) <.001
 ≥5 1.72 (1.53–1.93) <.001 1.82 (1.63–2.02) <.001

Abbreviations: APP, advanced practice provider; CCI, Charlson comorbidity index; CI, confidence interval; AOM, acute otitis media; OR, odds ratio; URI, respiratory infection.

Predictors of 14-Day Repeat Respiratory-Related Healthcare Contact in the Postimplementation Cohort

In the univariate model for 14-day repeat respiratory-related healthcare contact, relative to encounters of patients aged 0–2 years, all other age groups were less likely to return for a respiratory indication within 14 days (Supplementary Table 4). Additionally, urgent care, emergency medicine, telehealth, high monthly total clinic encounter volumes, patients with concomitant asthma, and CCI scores ≥5 were more likely to result in repeat healthcare contact. Receipt of an antibiotic prescription was associated with a lower rate of repeat contact (OR, 0.74 [95% CI, .67–.81]; P < .001), but was not one of the most important variables according to relative influence (Supplementary Figure 2). No differences were noted among provider type, patient sex, or patient race.

Three different multivariable models were fit for repeat respiratory-related healthcare contact comprising all, top 8, and top 5 variables by relative influence (Table 4, Supplementary Figure 2). When limiting the model to only the top 5 contributing variables, telehealth visit, department specialty, primary diagnosis, CCI, and age group had the most influence on repeat respiratory-related 14-day healthcare contact. When comparing the multivariable models on area under the ROC curve, they are similar (full model = 0.644, 8-variable model = 0.640, 5-variable model = 0.636), indicating that a reduced set of predictors is sufficient.

Table 4.

Multivariable Models for 14-Day Repeat Respiratory-Related Healthcare Contact in the Postintervention Cohort

Characteristic All Variables (n = 67 341) Top 8 (n = 68 436) Top 5 (n = 69 533)
OR (95% CI) P Value OR (95% CI) P Value OR (95% CI) P Value
Age group, y
 0–2
 3–18 0.48 (.45–.52) <.001 0.48 (.45–.52) <.001 0.49 (.46–.53) <.001
 19–65 0.35 (.32–.37) <.001 0.35 (.32–.38) <.001 0.35 (.32–.38) <.001
 >65 0.36 (.32–.41) <.001 0.37 (.32–.41) <.001 0.36 (.32–.40) <.001
Male sex 0.93 (.88–.98) .007
Race
 White
 American Indian/Alaska Native 1.05 (.73–1.46) .8
 Asian 0.90 (.76–1.06) .2
 Black or African American 0.87 (.77–.98) .023
 Native Hawaiian/Pacific Islander 0.72 (.39–1.20) .2
 Other 0.87 (.70–1.06) .2
Encounter season
 Apr–Sep
 Oct–Mar 1.04 (.98–1.10) .2
Asthma 1.26 (1.15–1.39) <.001 1.27 (1.16–1.40) <.001
Cystic fibrosis 0.55 (.09–1.86) .4
Pulmonary fibrosis 1.24 (1.02–1.51) .029
Bronchiectasis 0.99 (.72–1.34) >.9
Provider type
 APP
 Physician 0.92 (.86–.97) .004
 Trainee 1.23 (1.05–1.43) .010
Department specialty
 Primary care
 Urgent care 1.25 (1.16–1.34) <.001 1.28 (1.20–1.38) <.001 1.34 (1.25–1.44) <.001
 Emergency medicine 1.56 (1.45–1.67) <.001 1.52 (1.42–1.62) <.001 1.57 (1.47–1.68) <.001
Telehealth visit 1.77 (1.59–1.97) <.001 1.77 (1.59–1.96) <.001 1.93 (1.76–2.12) <.001
Primary diagnosis
 Bronchitis/bronchiolitis
 Influenza 0.78 (.69–.88) <.001 0.83 (.74–.93) .002 0.85 (.75–.95) .004
 Laryngitis/pharyngitis 0.79 (.69–.91) .001 0.83 (.72–.96) .011 0.83 (.72–.95) .008
 Other 1.11 (.51–2.15) .8 1.11 (.51–2.15) .8 1.12 (.51–2.17) .8
 Rhinitis 0.32 (.27–.38) <.001 0.33 (.28–.40) <.001 0.38 (.32–.44) <.001
 Serous AOM/ear disorders 0.80 (.71–.91) <.001 0.77 (.68–.87) <.001 0.77 (.68–.87) <.001
URI unspecified 0.80 (.74–.87) <.001 0.86 (.79–.93) <.001 0.86 (.80–.93) <.001
Total monthly clinic encounter volume
 Low
 Mild 0.96 (.87–1.06) .4 0.96 (.87–1.05) .4
 Moderate 1.10 (1.01–1.21) .039 1.10 (1.01–1.21) .040
 High 1.18 (1.08–1.30) <.001 1.19 (1.09–1.31) <.001
Encounter time
 Morning
 Afternoon 1.01 (.96–1.06) .8 1.01 (.95–1.06) .8
CCI score
 0
 1–2 1.32 (1.23–1.43) <.001 1.31 (1.22–1.42) <.001 1.40 (1.31–1.50) <.001
 3–4 1.68 (1.47–1.91) <.001 1.67 (1.47–1.90) <.001 1.75 (1.54–1.98) <.001
 ≥5 1.97 (1.73–2.25) <.001 1.99 (1.75–2.26) <.001 2.08 (1.84–2.35) <.001
Antibiotic prescribed 0.74 (.67–.81) <.001

Abbreviations: APP, advanced practice provider; CCI, Charlson Comorbidity Index; CI, confidence interval; AOM, acute otitis media; OR, odds ratio; URI, respiratory infection.

DISCUSSION

Our study adds to mounting evidence that targeted outpatient antibiotic stewardship programs are effective at reducing unnecessary or inappropriate antibiotic prescribing for URIs [12, 13, 15, 16, 20–24]. We observed a 48.4% relative reduction in prescriptions for Tier 3 URI following comprehensive outpatient antimicrobial stewardship program implementation, amounting to approximately 7300 unnecessary antibiotic prescriptions avoided. This finding was consistent among all specialties, regions, providers, and patient groups, thereby increasing external validity. Encounters where an antibiotic was prescribed were less likely to result in repeat respiratory-related healthcare contact for a respiratory indication within 14 days of index visit in the overall, pre-, and postintervention cohorts; however, the rate of repeat contact in patients who did not receive antibiotic therapy slightly decreased following implementation of the multifaceted intervention.

The decision of whether to prescribe or withhold an antibiotic is complicated, encompassing not only clinical, but also mutually dependent nonclinical factors, such as patient, provider, and healthcare system–related factors [25]. Even time of day has been correlated with the decision to prescribe antibiotics, with later appointments more likely to result in antibiotic prescription than earlier appointments, a phenomenon likely attributable to decision fatigue [26]. Socioeconomic patient factors not assessed in this report, including access to clinics and/or clinic location, may additionally impact prescribing decisions. Given the complexity of these influential factors, determining the relative magnitude of each is important to provide clarity to outpatient ASPs, particularly in the context of persistent inappropriate prescribing following intervention.

Using univariate and multivariable regression models in the postimplementation cohort, we were able to identify multiple factors impacting the decision to prescribe antibiotics. Consistent with prior research, we too found that afternoon appointments were more likely to result in unnecessary antibiotic prescriptions, even when controlling for other variables in the multivariate model. Interestingly, busier clinic months were associated with lower rates of unnecessary prescribing. One explanation for this might be the seasonality of cold and flu season, when encounter volumes peak and providers simultaneously feel more confident in attributing symptoms to circulating viruses. However, while encounter-level factors were influential in the overall model, we found that the most significant factors impacting the decision to prescribe antibiotics by relative influence are specific diagnosis, patient age, and patient comorbidities. Serous AOM/ear disorders were the diagnoses most strongly associated with antibiotic prescribing (OR, 2.27 [95% CI, 2.10–2.46]), which could indicate diagnostic uncertainty, a knowledge deficit, or diagnostic coding issues, all of which can be addressed with targeted follow-up interventions. The influence of advancing age and higher CCI on the propensity to prescribe antibiotics is not surprising in the context of the well-known influence of fear in prescribing decisions. In this patient population, fear of complications secondary to “missing” a bacterial diagnosis may be clouding the complete risk/benefit picture, wherein antibiotic-related complications, microbiota disruptions, and the development of antibiotic resistance are viewed as less common, less severe, and/or more abstract [27, 28].

Of particular importance is the association between antibiotic prescriptions and repeat respiratory-related 14-day respiratory healthcare contact, which was consistent in the overall, pre-, and postintervention cohorts. Previous studies have documented that antibiotic prescriptions are associated with higher patient satisfaction scores [29, 30], particularly if patients enter encounters expecting an antibiotic prescription [31]. It is possible that lack of antibiotic prescription drove certain patients (ie, the inconvincible patients) [32] to seek prescriptions elsewhere within the health system, thereby driving repeat contact. Such behaviors might be mitigated through patient education on diagnosis (eg, “you have a viral illness for which antibiotics have no proven benefit but may cause harm”), expectations (eg, “you may experience a lingering cough for up to 3 weeks”), and symptomatic management (eg, “take pseudoephedrine 60 mg by mouth every 4–6 hours as needed for congestion”). We provided a tool to providers (ie, Viral Rx pad) with patient education and preselected recommendations for over-the-counter medications to manage specific symptoms. This was available in multiple languages, and accessible in both in print and prepopulated progress note formats, with links directly to the resource from the prepopulated ambulatory order panel/clinical decision support tool.

The COVID-19 pandemic impacted the healthcare system in dramatic ways, including reduced clinic encounter volumes, hyperawareness of viral causes of URI, and a shift to telemedicine [33, 34]. In our study, we chose to exclude all encounters with COVID-19–related diagnosis codes. Even though antibiotics are not indicated for COVID-19, including these encounters in the overall denominators resulted in a very dramatic and clearly artificial drop in the prescribing rate, which coincided with fluctuations of COVID-19 encounters [35]. We also found increased use of telemedicine in the postimplementation (post–July 2021) cohort. Importantly, telehealth visits were associated with an increased rate of repeat respiratory-related healthcare contact, representing the fourth most important factor by relative influence behind patient age, department specialty, and primary diagnosis; however, we are unable to fully elucidate whether these repeat healthcare contact events represent planned in-person follow-ups or unplanned encounters for ongoing respiratory syndromes.

Limitations

Our study has several limitations, the most prevalent being a retrospective design and lack of randomization, which limits the ability to attribute causality of the intervention. Importantly, this study and the intervention period coincided with the COVID-19 pandemic, which could have influenced the study results in unmeasurable ways; however, as mentioned previously, COVID-19–related diagnoses were excluded from the analysis to limit the impact of an inflated denominator on Tier 3 prescribing rates. Utilizing encounter ICD-10 diagnosis codes may have resulted in some misclassification bias, including with use of unspecified codes, which comprised a large portion of our cohort (56% overall). However, diagnosis codes represent the most utilized method to classify encounters in this type of retrospective work, and methods similar to ours have been used in prior studies [1, 8, 23]. We additionally were unable to track delayed prescriptions (ie, prescriptions intended to only be filled if symptoms failed to improve with time), which may explain why we observed a higher rate of prescribing with serous AOM. Furthermore, we only tracked prescriptions written, rather than filled, which limits our ability to account for patient adherence as a confounding factor. Our primary balancing measure of 14-day repeat respiratory-related healthcare contact was broad and lacked the specificity to determine if an antibiotic prescription might have made a difference, nor did it account for planned follow-up compared to unplanned recontact with the care system. Last, we were unable to detect the utilization of certain interventions, such as patient-level counseling strategies, which might be important in preventing repeat respiratory-related healthcare contact for persistent symptoms that are within the expected course of illness for viral infections.

CONCLUSIONS

Implementation of a multifaceted outpatient antimicrobial stewardship initiative successfully reduced unnecessary antibiotic prescribing for URIs without increasing the rate of 14-day repeat respiratory-related healthcare contact. Persistent antibiotic prescribing after bundle implementation was noted among encounters for patients with advanced age and increasing comorbidities. Additional awareness about the risks and benefits of antibiotics in older, medically complex individuals may be helpful in further reducing unnecessary antibiotic prescriptions.

Supplementary Material

ofad585_Supplementary_Data

Contributor Information

Dan Ilges, Department of Pharmacy Services, Mayo Clinic Arizona, Phoenix, Arizona, USA.

Kelsey Jensen, Department of Pharmacy Services, Mayo Clinic Health System–Southeast Minnesota, Austin, Minnesota, USA.

Evan Draper, Department of Pharmacy Services, Mayo Clinic, Rochester, Minnesota, USA.

Ross Dierkhising, Division of Clinical Trials and Biostatistics, Mayo Clinic, Rochester, Minnesota, USA.

Kimberly A Prigge, Division of Family Medicine, Mayo Clinic, Rochester, Minnesota, USA.

Paschalis Vergidis, Division of Public Health, Infectious Diseases, and Occupational Medicine, Mayo Clinic, Rochester, Minnesota, USA.

Abinash Virk, Division of Public Health, Infectious Diseases, and Occupational Medicine, Mayo Clinic, Rochester, Minnesota, USA.

Ryan W Stevens, Department of Pharmacy Services, Mayo Clinic Health System–Southeast Minnesota, Austin, Minnesota, USA.

Supplementary Data

Supplementary materials are available at Open Forum Infectious Diseases online. Consisting of data provided by the authors to benefit the reader, the posted materials are not copyedited and are the sole responsibility of the authors, so questions or comments should be addressed to the corresponding author.

Notes

Acknowledgments. We acknowledge the contributions of Darrin Christopherson, MBA, Benjamin Anderson, PharmD, Laura Dinnes, PharmD, Nipunie Rajapakse, MD, MPH, Harry Powers, MD, Kevin Epps, PharmD, Kellie Arensman Hannan, PharmD, Sara Ausman, PharmD, Christina G. O’Connor, PharmD, Sarah Lessard, PharmD, Teresa Seville, MD, Jamilah Shubeilat, MD, and Angie Ton, MD, of the Mayo Clinic and affiliated health system sites, for their assistance in programmatic development and implementation across the Mayo Clinic Enterprise.

Author contributions. D. I., R. W. S., and R. D. had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: D. I., R. W. S., K. J., A. V., P. V., and K. A. P. Acquisition, analysis, or interpretation of data: D. I. and R. W. S. Drafting of the manuscript: D. I., R. W. S., and R. D. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: R. D. Administrative, technical, or material support: E. D. Supervision: A. V., P. V., K. J., and K. A. P.

Financial support. This work was partially funded by a grant from the Mayo Midwest Pharmacy Research Committee.

References

  • 1. Fleming-Dutra  KE, Hersh  AL, Shapiro  DJ, et al.  Prevalence of inappropriate antibiotic prescriptions among US ambulatory care visits, 2010–2011. JAMA  2016; 315:1864–73. [DOI] [PubMed] [Google Scholar]
  • 2. Centers for Disease Control and Prevention . Office-related antibiotic prescribing for persons aged ≤14 years—United States, 1993–1994 to 2007–2008. MMWR Morb Mortal Wkly Rep  2011; 60:1153–6. [PubMed] [Google Scholar]
  • 3. Shapiro  DJ, Hicks  LA, Pavia  AT, Hersh  AL. Antibiotic prescribing for adults in ambulatory care in the USA, 2007–09. J Antimicrob Chemother  2014; 69:234–40. [DOI] [PubMed] [Google Scholar]
  • 4. Hersh  AL, King  LM, Shapiro  DJ, Hicks  LA, Fleming-Dutra  KE. Unnecessary antibiotic prescribing in US ambulatory care settings, 2010–2015. Clin Infect Dis  2021; 72:133–7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5. Shehab  N, Patel  PR, Srinivasan  A, Budnitz  DS. Emergency department visits for antibiotic-associated adverse events. Clin Infect Dis  2008; 47:735–43. [DOI] [PubMed] [Google Scholar]
  • 6. Centers for Disease Control and Prevention (CDC) . Antibiotic resistance threats in the United States, 2019. Atlanta, GA: CDC; 2019. [Google Scholar]
  • 7. Sanchez  GV, Fleming-Dutra  KE, Roberts  RM, Hicks  LA. Core elements of outpatient antibiotic stewardship. MMWR Recomm Rep  2016; 65:1–12. [DOI] [PubMed] [Google Scholar]
  • 8. Stenehjem  E, Wallin  A, Fleming-Dutra  KE, et al.  Antibiotic prescribing variability in a large urgent care network: a new target for outpatient stewardship. Clin Infect Dis  2020; 70:1781–7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 9. Jones  BE, Sauer  B, Jones  MM, et al.  Variation in outpatient antibiotic prescribing for acute respiratory infections in the Veteran population: a cross-sectional study. Ann Intern Med  2015; 163:73–80. [DOI] [PubMed] [Google Scholar]
  • 10. Barnett  ML, Linder  JA. Antibiotic prescribing for adults with acute bronchitis in the United States, 1996–2010. JAMA  2014; 311:2020–2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11. Havers  FP, Hicks  LA, Chung  JR, et al.  Outpatient antibiotic prescribing for acute respiratory infections during influenza seasons. JAMA Netw Open  2018; 1:e180243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 12. McDonagh  MS, Peterson  K, Winthrop  K, Cantor  A, Lazur  BH, Buckley  DI. Interventions to reduce inappropriate prescribing of antibiotics for acute respiratory tract infections: summary and update of a systematic review. J Int Med Res  2018; 46:3337–57. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 13. Craddock  K, Molino  S, Stranges  PM, et al.  The impact of educational interventions on antibiotic prescribing for acute upper respiratory tract infections in the ambulatory care setting: a quasi-experimental study. J Am Coll Clin Pharm  2020; 3:609–14. [Google Scholar]
  • 14. Gerber  JS, Prasad  PA, Fiks  AG, et al.  Durability of benefits of an outpatient antimicrobial stewardship intervention after discontinuation of audit and feedback. JAMA  2014; 312:2569–70. [DOI] [PubMed] [Google Scholar]
  • 15. Johnson  MC, Hulgan  T, Cooke  RG, et al.  Operationalising outpatient antimicrobial stewardship to reduce system-wide antibiotics for acute bronchitis. BMJ Open Qual  2021; 10:e001275. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16. Meeker  D, Knight  TK, Friedberg  MW, et al.  Nudging guideline-concordant antibiotic prescribing: a randomized clinical trial. JAMA Intern Med  2014; 174:425–31. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17. Jensen  KL, Rivera  CG, Draper  EW, et al.  From concept to reality: building an ambulatory antimicrobial stewardship program. J Am Coll Clin Pharm  2021; 4:1583–93. [Google Scholar]
  • 18. Stevens  RW, Vergidis  P, Christopherson  D, et al.  Impact of a multifaceted, outpatient antimicrobial stewardship intervention bundle on unnecessary antimicrobial prescribing in upper respiratory tract infections (URI). Open Forum Infect Dis  2022; 9(Suppl 2):ofac492. [Google Scholar]
  • 19. Singh  B, Singh  A, Ahmed  A, et al.  Derivation and validation of automated electronic search strategies to extract Charlson comorbidities from electronic medical records. Mayo Clin Proc  2012; 87:817–24. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20. Keller  SC, Caballero  TM, Tamma  PD, et al.  Assessment of changes in visits and antibiotic prescribing during the agency for healthcare research and quality safety program for improving antibiotic use and the COVID-19 pandemic. JAMA Netw Open  2022; 5:e2220512. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21. Laude  JD, Kramer  HP, Lewis  M, et al.  Implementing antibiotic stewardship in a network of urgent care centers. Jt Comm J Qual Patient Saf  2020; 46:682–90. [DOI] [PubMed] [Google Scholar]
  • 22. Patel  D, Ng  T, Madani  LS, et al.  Antibiotic stewardship to reduce inappropriate antibiotic prescribing in integrated academic health-system urgent care clinics. Infect Control Hosp Epidemiol  2023; 44:736–45. [DOI] [PubMed] [Google Scholar]
  • 23. Stenehjem  E, Wallin  A, Willis  P, et al.  Implementation of an antibiotic stewardship initiative in a large urgent care network. JAMA Netw Open  2023; 6:e2313011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24. Davidson  LE, Gentry  EM, Priem  JS, Kowalkowski  M, Spencer  MD. A multimodal intervention to decrease inappropriate outpatient antibiotic prescribing for upper respiratory tract infections in a large integrated healthcare system. Infect Control Hosp Epidemiol  2023; 44:392–9. [DOI] [PubMed] [Google Scholar]
  • 25. Teixeira Rodrigues  A, Roque  F, Falcao  A, Figueiras  A, Herdeiro  MT. Understanding physician antibiotic prescribing behaviour: a systematic review of qualitative studies. Int J Antimicrob Agents  2013; 41:203–12. [DOI] [PubMed] [Google Scholar]
  • 26. Linder  JA, Doctor  JN, Friedberg  MW, et al.  Time of day and the decision to prescribe antibiotics. JAMA Intern Med  2014; 174:2029–31. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27. Kotwani  A, Wattal  C, Katewa  S, Joshi  PC, Holloway  K. Factors influencing primary care physicians to prescribe antibiotics in Delhi, India. Fam Pract  2010; 27:684–90. [DOI] [PubMed] [Google Scholar]
  • 28. Livorsi  D, Comer  A, Matthias  MS, Perencevich  EN, Bair  MJ. Factors influencing antibiotic-prescribing decisions among inpatient physicians: a qualitative investigation. Infect Control Hosp Epidemiol  2015; 36:1065–72. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 29. Ashworth  M, White  P, Jongsma  H, Schofield  P, Armstrong  D. Antibiotic prescribing and patient satisfaction in primary care in England: cross-sectional analysis of national patient survey data and prescribing data. Br J Gen Pract  2016; 66:e40–46. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30. Martinez  KA, Rood  M, Jhangiani  N, Kou  L, Boissy  A, Rothberg  MB. Association between antibiotic prescribing for respiratory tract infections and patient satisfaction in direct-to-consumer telemedicine. JAMA Intern Med  2018; 178:1558–60. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 31. Staub  MB, Pellegrino  R, Gettler  E, et al.  Association of antibiotics with veteran visit satisfaction and antibiotic expectations for upper respiratory tract infections. Antimicrob Steward Healthc Epidemiol  2022; 2:e100. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 32. Kohut  MR, Keller  SC, Linder  JA, et al.  The inconvincible patient: how clinicians perceive demand for antibiotics in the outpatient setting. Fam Pract  2020; 37:276–82. [DOI] [PubMed] [Google Scholar]
  • 33. Patel  SY, Mehrotra  A, Huskamp  HA, Uscher-Pines  L, Ganguli  I, Barnett  ML. Trends in outpatient care delivery and telemedicine during the COVID-19 pandemic in the US. JAMA Intern Med  2021; 181:388–91. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 34. Hartnett  KP, Kite-Powell  A, DeVies  J, et al.  Impact of the COVID-19 pandemic on emergency department visits—United States, 1 January 2019–30 May 2020. MMWR Morb Mortal Wkly Rep  2020; 69:699–704. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 35. Stevens  RW, Jensen  K, O’Horo  JC, Shah  A. Antimicrobial prescribing practices at a tertiary-care center in patients diagnosed with COVID-19 across the continuum of care. Infect Control Hosp Epidemiol  2021; 42:89–92. [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

ofad585_Supplementary_Data

Articles from Open Forum Infectious Diseases are provided here courtesy of Oxford University Press

RESOURCES