Discussion

In our study, pharmacists with and without formal ASP responsibilities contributed to antimicrobial stewardship, but the amount of time expended and levels of complexity of interventions differed significantly between groups. Although pharmacists without formal ASP responsibilities spent an average of 0.125 FTE on antimicrobial stewardship, pharmacists with formal ASP responsibilities dedicated ∼0.6 FTE on antimicrobial stewardship clinical activities, even though the average program had 1 FTE allocated for an ASP pharmacist. An increase in pharmacist FTE has been associated with increased effectiveness of an ASP, and our findings suggest that this could potentially be accomplished by providing more protected time for pharmacists with formal ASP responsibilities to focus on clinical stewardship activities. ^{Reference Doernberg, Abbo and Burdette3}

We detected minimal differences between stewardship strategies utilized by the institutions of the 2 groups, suggesting that any differences between the groups in terms of ASP activities completed were due to individual rather than institutional practices. Pharmacists with formal ASP responsibilities were just as likely to personally complete most basic interventions, but they were more likely to accomplish advanced and intermediate stewardship metrics. This finding may be explained by the higher proportion of ID training or certification among pharmacists with formal ASP responsibilities, which allowed them to make more advanced interventions as well as by the fact that pharmacists without formal ASP responsibilities were more likely to identify interventions by rounding, which may have led to a higher proportion of basic interventions such as IV-to-PO interchange. By empowering pharmacists without formal ASP responsibilities to complete more basic and intermediate-level interventions, pharmacists with formal ASP responsibilities may be free to focus on the more complex activities that they feel are more important, such as prospective audit and feedback, which has previously been shown to be one of the most effective strategies. ^{Reference Doernberg, Abbo and Burdette3,Reference Langford, Brown, Chan and Downing9,Reference Tamma, Avdic and Keenan10} A teamwork approach of pharmacists both with and without formal ASP responsibilities involved in stewardship activities may be optimal to successfully meet all metrics, irrespective of complexity.

Although the guidelines recommend that ASPs include a pharmacist with ID training, currently only 126 PGY2 infectious diseases pharmacy residency programs are accredited by the American Society of Health Systems Pharmacists in the United States. That is, there is a shortage of programs to formally train all pharmacists who participate in stewardship activities. ^{Reference Barlam, Cosgrove and Abbo2,Reference Heil, Kuti, Bearden and Gallagher11} This shortage was evident in our results: only one-third of pharmacists with formal ASP responsibilities had completed a second postgraduate year in ID and only 5% had completed an ID fellowship. Even though most respondents had completed a 1-year postgraduate program, this training alone may not adequately prepare pharmacists to practice in antimicrobial stewardship, especially regarding intermediate and advanced interventions. ^{Reference McGee, Mason-Callaway and Rollins12} Other ways to demonstrate competency include board certification or ASP certificate programs, but more than one-third of FR ASP respondents reported having neither.

Pharmacists with formal ASP responsibilities but without ID training or certification spent half as much time on direct ASP activities as those with training, despite having a similar number of pharmacist FTEs dedicated to the program. Possibly, the FTEs for the program may be split among multiple pharmacists who dedicated only part of their time to stewardship, but they still spent a higher proportion of their ASP time on basic activities such as IV-to-PO conversion and guideline development. There may also be pressure for ASPs, especially newly established programs, to achieve “low-hanging fruit” process-measure metrics to meet antimicrobial stewardship accreditation requirements, reduce costs, or to demonstrate their impact more easily. ^{Reference Khadem, Dodds Ashley, Wrobel and Brown13} However, improvements in outcome measures achieved by more advanced interventions are becoming increasingly important for both reimbursement and accreditation. ^{Reference Brotherton14} Additional education and training opportunities in ID and antimicrobial stewardship may allow these pharmacists to spend more time executing higher-level interventions. Multiple training or certificate programs are available, including a free online program from the Centers for Disease Control and Prevention (CDC); however, barriers to completion (e.g., awareness of these programs or the time or financial support to complete them) were not investigated in this study.

Our study had several limitations. A response rate could not be calculated because pharmacists could be members of >1 PRN, and membership also includes trainees and nonpracticing pharmacists, who were not eligible for the survey. The membership of ACCP includes clinical pharmacists from a variety of practice settings and backgrounds, which was reflected in the demographics of the respondents. The pharmacists without formal ASP responsibilities worked primarily in medium- or larger-sized teaching hospitals, and pharmacists without formal ASP responsibilities at smaller institutions may be less likely to attend rounds or be integrated with the primary teams to be able to make interventions as easily. Another limitation is that respondents only reported whether or not they performed a stewardship intervention without information on frequency or effectiveness. Previous studies have demonstrated that dedicated ASP pharmacists are more effective than decentralized pharmacists, so it would be important to monitor activities shifted to pharmacists without formal ASP responsibilities to ensure that they are being completed successfully. ^{Reference Bessesen, Ma and Clegg6,Reference DiDiodato and McAthur7} As ASPs continue to expand, it will be important to evaluate how pharmacists’ roles and training impact the effectiveness and efficiency of various strategies to determine how best to collaborate on the work of antimicrobial stewardship.

In conclusion, antimicrobial stewardship activities differ between pharmacists with and without formal ASP responsibilities. Each group utilizes different methods to identify potential antimicrobial stewardship interventions and practices to make recommendations. Due to the lack of adequate training programs and substantial amount of time pharmacists with formal ASP responsibilities spend on non-ASP, administrative, and research activities, many day-to-day clinical ASP activities are performed by pharmacists who lack antimicrobial stewardship certification, formal ID training, and/or do not have formal ASP job titles. Pharmacists responsible for ASP who lack formal antimicrobial stewardship or ID training should seek opportunities to obtain board certification in ID and/or ASP certification to ensure that pharmacists who complete more advanced stewardship activities are appropriately qualified while engaging frontline pharmacists without formal ASP responsibilities in basic and intermediate-level antimicrobial stewardship activities. Future research should explore barriers to ASP training for these pharmacists as well as for other clinicians.