Statistical Process Control Charts Research Articles

Reducing postoperative hypothermia in infants: Quality improvement in China.

Unintended postoperative hypothermia in infants is associated with increased mortality and morbidity. We noted consistent hypothermia postoperatively in more than 60% of our neonatal intensive care (NICU) babies. Therefore, we set out to determine whether a targeted quality improvement (QI) project could decrease postoperative hypothermia rates in infants. Our SMART aim was to reduce postoperative hypothermia (<36.5°C) in infants from 60% to 40% within 6 months. This project was approved by IRB at Guangzhou Women and Children's Medical Center, China. The QI team included multidisciplinary healthcare providers in China and QI experts from Children's Hospital of Philadelphia, USA. The plan-do-study-act (PDSA) cycles included establishing a perioperative-thermoregulation protocol, optimizing the transfer process, and staff education. The primary outcome and balancing measures were, respectively, postoperative hypothermia and hyperthermia (axillary temperature < 36.5°C, >37.5°C). Data collected was analyzed using control charts. The factors associated with a reduction in hypothermia were explored using regression analysis. There were 295 infants in the project. The percentage of postoperative hypothermia decreased from 60% to 37% over 26 weeks, a special cause variation below the mean on the statistical process control chart. Reduction in hypothermia was associated with an odds of 0.17 (95% CI: 0.06-0.46; p <.001) for compliance with the transport incubator and 0.24 (95% CI: 0.1-0.58; p =.002) for prewarming the OR ambient temperature to 26°C. Two infants had hyperthermia. Our QI project reduced postoperative hypothermia without incurring hyperthermia through multidisciplinary team collaboration with the guidance of QI experts fromthe USA.

Improving Sexual History Documentation in Teenagers.

Teen access to sexual health care is essential. The 21st Century Cures Act mandates that most electronic health information be shared with patients; no standard exists for how to meet this mandate for teens and their proxy caregivers. Our confidential shared teen sexual history (SexHx) section, which is not note-based, allows clinicians to easily find information, promotes clinical decision support, and protects privacy. Nevertheless, significant variability existed in SexHx section usage, SexHx documentation, and teen note-sharing practices. For teens (aged 12-17) admitted to the Pediatric Hospital Medicine service, we aim to increase the use of the SexHx section by 10% and increase History and Physical notes (H&Ps) shared with teens by 5% over 12 months. Quality improvement methodology and tools were used to conduct a barrier analysis and implement a series of interventions, which included education, training, and electronic health record clinical decision support. Statistical process control charts were used to examine the impact of the interventions. At baseline, from April to July 2021, sexual activity was documented or reviewed in the SexHx section for 56% of teen patients. Over the intervention period, the center line shifted to 72%. At baseline, 76% of teen H&Ps were shared with patients. The percentage of H&Ps shared revealed a center-line shift to 81% throughout the intervention period. The shared teen SexHx section is an innovative tool for capturing sensitive patient history discretely. We demonstrated increased and sustained SexHx section use and H&P note-sharing in this quality improvement initiative.

Reducing NICU Unplanned Extubations From Tube Dislodgement.

Unplanned extubations (UEs) can be a frequent problem and are associated with adverse outcomes. This quality improvement initiative sought to reduce UEs from tube dislodgement in a level IV NICU utilizing methods applicable to other ICUs and performed with minimal monetary funds. From January 2019 to July 2023, an interdisciplinary quality improvement team used the Model for Improvement and performed sequential interventions to improve the outcome measure of UEs per 100 ventilator days. Process measures included adherence to a modified, site-specific UE care bundle derived from the Solutions for Patient Safety network, whereas the number of endotracheal tube-related pressure injuries was used as a balancing measure. Statistical process control charts and established rules for special cause variation were applied to analyze data. Sequential interventions reduced the rate of UEs from a baseline of 2.3 to 0.6 UEs per 100 ventilator days. Greater than 90% adherence with the UE care bundle and apparent cause analysis form completion occurred since December 2020. There were no endotracheal tube-related pressure injuries. A sustained reduction in UEs was demonstrated. Leveraging a multidisciplinary team allowed for continuous UE analysis, which promoted tailored consecutive interventions. UE care bundle audits and the creation of a postevent debrief guide, which helped providers share a common language, were the most impactful interventions. Next steps include disseminating these interventions to other ICUs across our hospital enterprise. These low-cost interventions can be scalable to other NICUs and PICUs.

Reducing ambulatory central line-associated bloodstream infections: A family-centered approach.

Ambulatory central line-associated bloodstream infections (CLABSIs) cause significant morbidity and mortality, especially in pediatric oncology. Few studies have had interventions directed toward caregivers managing central lines (CL) at home to reduce ambulatory CLABSI rates. We aimed to reduce and sustain our ambulatory CLABSI rate by 25% within 3years of the start of a quality improvement intervention. Plan-do-study-act cycles were implemented beginning April 2016. The main intervention was a family-centered CL care skill development curriculum for external CLs. Training began upon hospital CL insertion, followed by an ambulatory teach-back program to achieve home caregiver CL care independence. Other changes included: standardizing ambulatory nurse CL care practice (audits, a train the nurse trainer process, and workshops for independent home care agencies); developing aids for trainers and caregivers; providing supplies for clean surfaces; wide dissemination of the program; and minimizing opportunities of CLABSI (e.g., standardizing timing of CL removal). The outcome measure was the ambulatory CLABSI rate (excluding mucosal barrier injury laboratory-confirmed bloodstream infection), compared pre intervention (January 2015 to March 2016) to post intervention, including 2years of sustainability (April 2016 to June 2023), using statistical process control charts. We estimated the total number of CLABSI and associated healthcare charges prevented. The ambulatory CLABSI rate decreased by 52% from 0.25 to 0.12 per 1000 CL days post intervention, achieved within 27months; 117 CLABSI were prevented, with $4.2 million hospital charges and 702 hospital days avoided. Focusing efforts on home caregivers CL care may lead to reduction in pediatric oncology ambulatory CLABSI rates.

Increasing access to cataract surgery in Counties Manukau by optimising the clinical pathway: a quality improvement report.

To streamline the cataract surgery pathway to improve the time from first specialist assessment (FSA) to surgery, while reducing the clinical priority assessment criteria (CPAC) score from 55 to 50. A quality improvement project using Lean Six Sigma tools and the Model for Improvement. Most data were collected from the i.Patient Manager (iPM) system and analysed using statistical process control charts. Change interventions included combining FSA and pre-admission clinics (PAC); post-operative telephone review by non senior medical officers (SMO); and using our own surgeons in private theatres. The standard cataract pathway was reduced from 5 to 3 appointments. This removed 1,514 hours of appointments, released 113 SMO hours and saved patients NZ$156,000 in indirect costs over a year. The average waiting time from FSA to surgery decreased from 90 to 77 days (-13.5%). The number of overdue patients reduced from 127 to 44 (-35%). The average number of patients on the FSA waiting list dropped from 322 to 205 (-40%). There was no change to the proportions of surgeries or appointment attendance rates by ethnicity. Average monthly cataract surgeries increased from 192 to 215 (+12%), and the CPAC score threshold was decreased to 50 in February 2021. Despite significant demand pressures, and the disruptions of COVID-19, we were able to reduce the CPAC score for accessing cataract surgery by optimising the clinical pathway to better utilise staff capacity and maximise value for patients.

Implementing Inpatient Social Needs Screening in an Urban Tertiary Care Children's Hospital.

The American Academy of Pediatrics recommends screening for unmet social needs, and the literature on inpatient screening implementation is growing. Our aim was to use quality improvement methods to implement standardized social needs screening in hospitalized pediatric patients. We implemented inpatient social needs screening using the Model for Improvement. An interprofessional team trialed interventions in a cyclical manner using plan-do-study-act cycles. Interventions included a structured screening questionnaire, standardized screening and referrals workflows, electronic health record (EHR) modifications, and house staff education, deliberate practice, and feedback. The primary outcome measure was the percentage of discharged patients screened for social needs. Screening for social needs was defined as a completed EHR screening questionnaire or a full social work evaluation. Process and balancing measures were collected to capture data on screening questionnaire completion and social work consultations. Data were plotted on statistical process control charts and analyzed for special cause variation. The mean monthly percentage of patients screened for social needs improved from 20% at baseline to 51% during the intervention period. Special cause variation was observed for the percentage of patients with completed social needs screening, EHR-documented screening questionnaires, and social work consults. Social needs screening during pediatric hospitalization can be implemented by using quality improvement methods. The next steps should be focused on sustainability and the spread of screening. Interventions with greater involvement of interdisciplinary health care team members will foster process sustainability and allow for the spread of screening interventions to the wider hospitalized pediatric population.

Optimizing the Use of Dose Error Reduction Software on Intravenous Infusion Pumps.

Intravenous infusions have the potential to cause significant harm in patients and are associated with a high rate of adverse drug events and medication errors. Infusion pumps with dose error reduction software (DERS) can be used to reduce errors by establishing safe infusion parameters. In 2019, a quality improvement project was initiated with the aim to increase DERS compliance from 46% to 75% at our specialty institution by October 1, 2022. An interdisciplinary group was tasked with improving compliance with DERS by identifying key drivers, including informed staff, engaged staff, and an accurate smart pump library. We used the Model for Improvement framework to guide this improvement project, and Plan-Do-Study-Act (PDSA) cycles were used to plan for interventions. PDSA cycles included drug library updates, education, and unit-level compliance reporting. Weekly average DERS compliance was monitored as the outcome measure, and weekly pump alerts per 100 infusions were monitored as a balancing measure; statistical process control charts were used to monitor measures from 2018 to 2022. Over the course of 25 months, 8 PDSA cycles resulted in 5 centerline improvements from a baseline mean of 46% to a final mean of 78%. Pump alerts per 100 infusions decreased from 15.9 to 6.4 with the first PDSA cycle and then continued to decrease to 3.9 with subsequent interventions. Although features like DERS can help ensure safe medication administration, continuous improvement efforts to increase DERS compliance without increasing alert burden are needed to ensure that benefits of this technology are optimized.

Increasing the Use of Enteral Antibiotics in Hospitalized Children With Uncomplicated Infections.

Route of administration is an important component of antimicrobial stewardship. Early transition from intravenous to enteral antibiotics in hospitalized children is associated with fewer catheter-related adverse events, as well as decreased costs and length of stay. Our aim was to increase the percentage of enteral antibiotic doses for hospital medicine patients with uncomplicated common bacterial infections (community-acquired pneumonia, skin and soft tissue infection, urinary tract infection, neck infection) from 50% to 80% in 6 months. We formed a multidisciplinary team to evaluate key drivers and design plan-do-study-act cycles. Interventions included provider education, structured discussion at existing team huddles, and pocket-sized printed information. Our primary measure was the percentage of antibiotic doses given enterally to patients receiving other enteral medications. Secondary measures included antibiotic cost, number of peripheral intravenous catheters, length of stay, and 7-day readmission. We used statistical process control charts to track our measures. Over a 6-month baseline period and 12 months of improvement work, we observed 3183 antibiotic doses (888 in the baseline period, 2295 doses during improvement work). We observed an increase in the percentage of antibiotic doses given enterally per week for eligible patients from 50% to 67%. We observed decreased antibiotic costs and fewer peripheral intravenous catheters per encounter after the interventions. There was no change in length of stay or readmissions. We observed increased enteral antibiotic doses for children hospitalized with common bacterial infections. Interventions targeting culture change and communication were associated with sustained improvement.

Improving Access to Care, Patient Costs, and Environmental Impact Through a Community Outreach Lung Cancer Rapid Assessment Clinic.

In Southeastern Ontario, increased patient distance from the regional lung cancer diagnostic assessment program (LDAP) is associated with a lower likelihood of patient care via LDAP while receiving care via LDAP is associated with improved survival. We implemented an LDAP outreach clinic to provide specialist assessment for patients with suspected lung cancer at a regional community hospital and assessed the impact on timeliness and accessibility of care. The Kingston Health Sciences Centre LDAP team engaged with community hospital partners to develop and launch the LDAP outreach clinic. We performed a retrospective chart review of LDAP patients (N = 1,070) before (August-November 2021; n = 234) and after implementation of the outreach clinic (November 2021-October 2022; n = 836). Descriptive data are reported as No. (%). Unpaired t tests and statistical process control charts assess for significance. A cost analysis of out-of-pocket patient costs related to travel and parking is presented in 2022 Canadian dollars (CAD). Compared with a 3-month matched time period before (August-October 2021) and after outreach clinic (August-October 2022), the mean time from referral to assessment and time from referral to diagnosis decreased from 20.3 to 14.4 days (P = .0019) and 40.0 to 28.9 days (P = .0007), respectively. Over 12 months, the total patient travel was reduced by 8,856 km, which combined with parking cost-savings, resulted in patient out-of-pocket savings of CAD $5,755.60 (CAD $47.60/patient). Accounting for physician travel, the total travel saved was 5,688 km, corresponding to reduced CO2 emissions by 1.9 tCO2. Implementation of a lung cancer outreach clinic led to improved timeliness of care, patient cost-savings, and reduced carbon footprint while serving patients in their community.

Imaging in a Pandemic: How Lack of Intravenous Contrast for Computed Tomography Affects Emergency Department Throughput.

During the coronavirus 2019 pandemic, hospitals in the United States experienced a shortage of contrast agent, much of which is manufactured in China. As a result, there was a significantly decreased amount of intravenous (IV) contrast available. We sought to determine the effect of restricting the use of IV contrast on emergency department (ED) length of stay (LOS). We conducted a single-institution, retrospective cohort study on adult patients presenting with abdominal pain to the ED from March 7-July 5, 2022. Of 26,122 patient encounters reviewed, 3,028 (11.6%) included abdominopelvic CT with a complaint including "abdominal pain." We excluded patients with outside imaging and non-ED scans. Routine IV contrast agent was administered to approximately 74.6% of patients between March 7-May 6, 2022, when we altered usage guidelines due to a nationwide shortage. Between May 6-July 5, 2022, 32.8% of patients received IV contrast after institutional recommendations were made to limit contrast use. We compared patient demographics and clinical characteristics between groups with chi-square test for frequency data. We analyzed ED LOS with nonparametric Wilcoxon rank-sum test for continuous measures with focus before and after new ED protocols. We also used statistical process control charts and plotted the 1, 2 and 3 sigma control limits to visualize the variation in ED LOS over time. The charts include the average (mean) of the data and upper and lower control limits, corresponding to the number of standard deviations away from the mean. After use of routine IV contrast was discontinued, ED LOS (229.0 vs 212.5 minutes, P = <0.001) declined by 16.5 minutes (95% confidence interval -10, -22). Intravenous contrast adds significantly to ED LOS. Decreased use of routine IV contrast in the ED accelerates time to CT completion. A policy change to limit IV contrast during a national shortage significantly decreased ED LOS.

Strategies to Improve COVID-19 Vaccination in a Pregnant, Marginalized Population: Quality Improvement Project.

Objectives. To improve COVID-19 vaccination rates in pregnant and recently pregnant women from a baseline rate of 30.8% to 60% over 6 months in a marginalized population. Methods. This quality improvement (QI) project was conducted in a federally qualified health center in Western New York between November 2021 and April 2022, using a Lean Six Sigma method. The QI team created a fishbone diagram, process flow map, and driver diagram. Significant barriers were multiple preferred languages, limited health literacy, and a knowledge gap. Increased vaccination rates were the outcome measure. The process measures were attendance at educational events and increased knowledge in community health workers (CHWs) and doulas. Education for CHWs and patients, creating multilingual educational resources, and motivational interviewing sessions for CHWs and patients were the major interventions. We performed data analysis by using weekly run charts and a statistical process control chart. Results. We achieved a sustainable increase in the COVID-19 vaccination rates in women from 30.0% to 48% within 6 months. Conclusions. Patient education in their preferred languages and at health literacy levels and CHWs' engagement played a crucial role in achieving success. (Am J Public Health. 2024;114(S4):S322-S329. https://doi.org/10.2105/AJPH.2024.307665).

Improvement Science Increases Routine Lipid Screening in General Pediatric Cardiology

ObjectiveTo evaluate the effectiveness of patient education, physician counseling, and point-of-care (POC) testing on improving adherence to lipid screening national guidelines in a general pediatric cardiology practice (2017-2023). Study designRegional primary care providers were surveyed regarding lipid screening practices. Key drivers were categorized (physician, patient, system) with corresponding interventions. Pediatric cardiologists started offering lipid screening during regular visits by providing families with preventive cardiovascular education materials and lab phlebotomy testing. System re-design included educational posters, clinical intake protocol, physician counseling, electronic health record integration, and POC testing. Run charts and statistical process control charts measured screening rates and key processes. ResultsThe primary care survey response rate was 32% (95/294); 97% supported pediatric cardiologists conducting routine lipid screening. Pediatric cardiology mean baseline lipid screening rate was 0%, increased to 7% with patient education, and to 61% after system redesign including POC testing. Screening rates among 1,467 patients were similar across age groups (P = 0.98). More patients received lipid screening by POC (91.7%) compared with phlebotomy (8.3%). Lipid abnormalities detected did not differ by screening methodology (P = 0.49). ConclusionPatient education, counseling, and POC testing improved adherence to national lipid screening guidelines, providing a possible model for primary care implementation.

Improving Parental Knowledge of Medically Complex Neonates Through Scheduled Conferences.

Reports of parental dissatisfaction from incomplete or inconsistent information led to a quality improvement (QI) project to establish planned family conferences at 10 days and 1 month of life, for 50% of the medically complex neonates admitted to a neonatal intensive care unit within 1 year. A QI team instituted a system in which social workers scheduled family conferences and a neonatologist conducted the conferences. Team members tracked measures using statistical process control charts over 21 months. The QI team scheduled conferences for greater than 80% of eligible families, with an 86% completion rate on days 10 and 30, exceeding project goals of 50%. The majority of the families surveyed were satisfied with the meetings. Only 2% of parents surveyed found meetings burdensome, compared to 14% of physicians. A sustainable method for scheduling meetings and preparation for conferences, including the use of a template led to success.

Ensuring safe and equitable discharge: a quality improvement initiative for individuals with hypertensive disorders of pregnancy

ObjectiveTo improve timely and equitable access to postpartum blood pressure (BP) monitoring in individuals with hypertensive disorders of pregnancy (HDP).MethodsA quality improvement initiative was implemented at a large academic medical...

Robust Control Chart Application in Semiconductor Manufacturing Process

Statistical Process Control (SPC) charts are frequently used in the semiconductor manufacturing environment to monitor process quality and detect special-cause variations, hence, to take corrective actions when necessary. The important aspects of control charts to consider on production floors are identifying the primary objective of implementing control charts, the type of data to monitor and the most appropriate control limits to establish. When the quality data is a type of attribute data like the proportion of defectives from a production lot, a p-chart approach is most suitable. In p-chart applications, although the assumption of normally distributed process data is not mandatory, the widespread practice is to assume the normal distribution of process data when establishing the control limits. Yet again, the reality of industrial settings is that process data are most likely influenced by outliers, resulting in highly skewed distributions. This paper addresses these issues by proposing robust SPC charting techniques to detect special-cause variations in the semiconductor manufacturing processes. Here, we present a case study of a semiconductor company in Malaysia, Dominant Opto Technologies Sdn. Bhd. to propose three robust statistical approaches for monitoring the proportion of defectives in production lots. We apply M-estimates, median, and interquartile range to calculate the upper control limits (UCL) and found that robust estimators are more effective in detecting early process deterioration and capturing the out-of-control (OOC) conditions better than traditional control charts. By proposing robust methods, this study enlightens the practical aspects of process quality improvement for real-life manufacturing setups. Because a high OOC rate may impact manufacturing productivity, we recommend the decision-makers choose the types of control charts based on the implications of each robust approach toward quality and productivity. The significance of this study includes providing insights into setting up the appropriate attribute control charts for detecting defective proportions for professionals and SPC researchers working in these areas.

Improving Employee Safety Through a Comprehensive Patient Behavioral Program.

Health care workers in the United States are facing increasing rates of exposure to aggressive behavior, resulting in an increase in employee injuries related specifically to patient behavioral events. By leveraging interprofessional collaboration and system-level innovation, we aimed to reduce the rate of employee injuries related to patient behavioral events at a children's hospital by 50% over a 3-year period. An interdisciplinary quality improvement team comprising physicians, behavior analysts, nursing, and other key stakeholders developed a comprehensive behavior program in our children's hospital. The team developed 5 key pillars: aggression mitigation tools, clinical resources, advanced training, screening and management, and behavior emergency response. The outcome measure was rate of reported employee safety events related to patient behavioral events. This was tracked via prospective time series analysis statistical process control chart using established rules to detect special cause variation. The average rate of employee injuries resulting from patient behavioral events decreased from 0.96 to 0.39 per 1000 adjusted patient-days, with special cause variation observed on a statistical process control U-chart. This improvement has been sustained for 16 months. Staff members who experienced injuries included nurses and patient technicians, with common antecedents to injuries including medical interventions or patient requests that could not be safely met. A unified and multimodal system aimed to address pediatric patient behavioral events can reduce employee injuries and foster a culture of employee safety in the pediatric inpatient setting.

Using quality improvement to pursue equity: lessons from healthcare

Against a backdrop of stalling life expectancy, the COVID-19 pandemic highlighted the need to tackle inequities in healthcare. Quality improvement has become an increasingly recognised way of tackling complex problems in healthcare. This article presents a step-by-step approach for the use of quality improvement to pursue equity at an NHS provider in England. The Model for Improvement was used to set an aim, develop a theory of change and measures, and test change ideas through plan-do-study-act cycles. A five-step sequence of improvement was used to provide a structured approach to identifying and tackling problems. Projects were designed to use a time series testing strategy in which baseline data were collected, a change was introduced and data continued to be collected over time to assess improvement. The results of three teams that have demonstrated sustained improvements were analysed using statistical process control charts. The teams' achievements included a 27% increase in access to early intervention mental health services for ethnic minority groups; a 92% reduction in racist incidents on inpatient wards; and a reduction in the gap between cervical screening rates for different age groups from 8% to 3%. Quality improvement offers those closest to the delivery of care a way of systematically making improvements in equity. Further opportunities for the field include the use of experimental designs to test combinations of interventions and potential scalability of quality improvement methods across systems with multiple partners.

ShinyMBA: a novel R shiny application for quality control of the multiplex bead assay for serosurveillance studies

The multiplex bead assay (MBA) based on Luminex xMAP technology can be used as a tool to measure seroprevalence as part of population immunity evaluations to multiple antigens in large-scale serosurveys. However, multiplexing several antigens presents challenges for quality control (QC) assessments of the data because multiple parameters must be evaluated for each antigen. MBA QC parameters include monitoring bead counts and median fluorescence intensity (MFI) for each antigen in plate wells, and performance of assay controls included on each plate. Analyzing these large datasets to identify plates failing QC standards presents challenges for many laboratories. We developed a novel R Shiny application, shinyMBA, to expedite the MBA QC processes and reduce the risk of user error. The app allows users to rapidly merge multi-plate assay outputs to evaluate bead count, MFI, and performance of assay controls using statistical process control charts for all antigen targets simultaneously. The utility of the shinyMBA application and its various outputs are demonstrated using data from 32 synthetic xPONENT files with 3 multiplex antigens and two population serosurveillance studies that evaluated 1200 and 3871 samples, respectively, for 20 multiplexed antigens. The shinyMBA open-source code is available for download and modification at https://github.com/CDCgov/shinyMBA. Incorporation of shinyMBA into Luminex serosurveillance workflows can vastly improve the speed and accuracy of QC processes.

Improving Accuracy of Medication Reconciliation for Hospitalized Children: A Quality Project.

Medication reconciliation is a complex, but necessary, process to prevent patient harm from medication discrepancies. Locally, the steps of medication reconciliation are completed consistently; however, medication errors still occur, which suggest process inaccuracies. We focused on removal of unnecessary medications as a proxy for accuracy. The primary aim was to increase the percentage of patients admitted to the pediatric hospital medicine service with at least 1 medication removed from the home medication list by 10% during the hospital stay by June of 2022. Using the Model for Improvement, a multidisciplinary team was formed at a children's hospital, a survey was completed, and multiple Plan-Do-Study-Act cycles were done focusing on: 1. simplifying electronic health record processes by making it easier to remove medications; 2. continuous resident education about the electronic health record processes to improve efficiency and address knowledge gaps; and 3. auditing charts and real-time feedback. Data were monitored with statistical process control charts. The project exceeded the goal, improving from 35% to 48% of patients having at least 1 medication removed from their home medication list. Improvement has sustained for 12 months. The combination of interventions including simplifying workflow, improving education, and enhancing accountability resulted in more patients with medications removed from their home medication list.

A nurse-driven penicillin allergy risk score in the preoperative setting was associated with increased cefazolin use perioperatively

Study objectiveTo characterize and assess the effects of a preoperative, nurse-driven penicillin allergy risk stratification tool on rates of perioperative cefazolin and second-line antibiotic use. DesignQuasi-experimental quality improvement study of penicillin-allergic surgical patients undergoing procedures for which cefazolin is indicated. SettingOutpatient Perioperative Care Clinic (PCC) for preoperative surgical patients at a tertiary care center. Patients670 and 1371 adult penicillin-allergic PCC attendants and non-attendants, respectively. InterventionA paper penicillin allergy risk stratification questionnaire was administered during the PCC visit. Nurses were educated on its use. MeasurementsAntibiotic (cefazolin, clindamycin, vancomycin) use rates in the 24 months before and 17 months after intervention implementation in November 2020 (November 2018 – April 2022) were assessed in penicillin-allergic PCC attendants with statistical process control charts. Multivariable logistic regression assessed antibiotic use rates pre- and post-intervention adjusting for age, sex, surgical specialty and penicillin allergy history severity. Similar analyses were done in penicillin-allergic PCC non-attendants. Main resultsOf 670 penicillin-allergic PCC attendants, 451 (median [IQR] age, 66 (Sousa-Pinto et al., 2021 [14])) were analyzed pre-intervention and 219 (median [IQR] age, 66 (Mine et al., 1970 [13])) post-intervention. One month after implementation, process measures demonstrated an upward shift in cefazolin use for PCC attendants versus no shift or other special cause variation for PCC non-attendants. There were increased odds of cefazolin use (aOR 1.67, 95% CI [1.09–2.57], P = 0.019), decreased odds of clindamycin use (aOR 0.61, 95% CI [0.42–0.89], P = 0.010) and decreased odds of vancomycin use (aOR 0.56, 95% CI [0.35–0.88], P = 0.013) in PCC attendants post-intervention. This effect did not occur in PCC non-attendants. There was no increase in perioperative anaphylaxis post-intervention. ConclusionsA simple penicillin allergy risk stratification tool implemented in the preoperative setting was associated with increased use of cefazolin and decreased rates of second-line agents post implementation.