The EPIDEM Model of Quality Improvement: A Q&A with Yaolin Zhou, MD

By Corey Whelan - February 07, 2023


This interview has been edited for clarity and length.  

Quality improvement (QI) is necessary for improving laboratory services and ultimately patient outcomes, but existing QI tools can be complicated and confusing to implement in real world settings, such as the clinical laboratory.  

Yaolin Zhou, MD, is an Associate Professor of Pathology at the Department of Pathology and Laboratory Medicine, East Carolina University, Brody School of Medicine. Her background in public policy at Duke University, medical education at Mayo Medical School, and training in anatomic, clinical pathology and as a chief quality resident at University of Alabama Birmingham, followed by Molecular Genetic Pathology fellowship at Cleveland Clinic, led her to develop EPIDEM, an easily implementable QI method.  

Innovative yet simple, EPIDEM can be used alone or in conjunction with other QI models and tools. Critical Values reached out to Dr. Zhou to learn more about EPIDEM and its applications for pathology and laboratory medicine.  

Critical Values (CV): Can you share your approach to patient care and what has shaped your view of the pathologist’s role? 

Yaolin Zhou (YZ): I studied public policy at Duke University, which is a multidisciplinary major that includes political science, economics, psychology, sociology, and ethics. I was trained to analyze issues from a “big picture” perspective. Public policy includes political analysis, which is framing issues in a way that is politically palatable and economic analysis, which includes studying the impact of the decisions from a cost-benefit perspective.  

Public Policy taught me the skills to analyze and solve problems, but Mayo Medical School exemplified a collaborative approach toward patient care. Mayo Clinic’s primary value is “the needs of the patient come first.” Putting the needs of the patient first requires setting egos aside and taking a team approach, recognizing the contribution of all members of the healthcare team.  

Later as a pathology trainee, however, I was struck by how pathologists referred to other physicians as “clinicians.” It creates an “us versus them” mentality. As a pathologist, I am a clinician who is also part of the clinical team. Importantly, pathologists must use clinical judgement to interpret laboratory tests in their proper context. 

One of my responsibilities as a resident was to approve send-out tests. These are typically quite expensive for the hospital as they cannot be reimbursed for hospitalized patients. I developed my own approach for approving these tests. I first reviewed the medical records of the patients to understand the clinical history. From there, I would initiate conversations with the ordering provider, typically a resident. I referred to “our patients” rather than “their patients” and confirmed my understanding of the clinical situation and their goals in ordering the particular test, before proceeding to recommend alternative testing strategies. I found this approach to be very effective, as it helped me develop a rapport and build trust. As a second-year pathology resident, the chief neurology resident invited me to present about laboratory testing for the neurology department. That was my first presentation of its kind and I have continued to give such presentations to healthcare professionals in various specialties since then.  

CV: You have been at quite a few different institutions. How did this contribute to EPIDEM? 

YZ: I feel extraordinarily privileged to train at some of the world’s finest healthcare institutions; however, in my first attending position as the Director of Molecular Pathology at the University of Oklahoma, I became concerned about the ethical principle of distributive justice: all patients deserve the recommended standard level of care, but patients and the providers and institutions that care for them are so varied. How can we provide all patients with the necessary medical care?  

Moreover, as the newly appointed chair of the University of Oklahoma’s Physicians Practice Quality Improvement committee, it became quickly apparent that even the leaders who were on this committee felt uncomfortable with implementing and teaching QI. I attributed this to how Quality Improvement has been overcomplicated with foreign terms, acronyms, worksheets, and forms, that it was impractical for even trained QI “experts” to do QI in real life. 

One night, as I was driving home, feeling frustrated and powerless, I thought, “What are we actually trying to do here?” I came up with the acronym EPIDEM to represent the steps of quality improvement as well as a vision for an EPIDEMic of healthcare professionals, working together to improve patient care: Exploration, Promotion, Implementation, Documentation, Evaluation, and Modification. The “ic” isn’t actually part of the acronym, but it could represent “improving continuously.” 

CV: What makes EPIDEM unique compared to other existing QI models? 

YZ: EPIDEM is a simple way of making QI attainable to anyone, regardless of where you are in the hospital hierarchy and regardless of any prior QI training. You can learn EPIDEM in 30 minutes and apply it to any challenge you may have in your professional or personal life. If you have a Lean Six Sigma Black Belt, EPIDEM should make sense for you too. What makes EPIDEM unique is that it requires no formal training. It is common sense, and it can work in work or in real life.  

The first steps are exploration and promotion, which are often neglected in other QI models. Exploration is critical as healthcare organizations and the people we work with and serve are complex. Other QI models assume that we have the answers and can jump in with a solution. EPIDEM requires first understanding the local culture, context, and resources, and developing trust and relationships prior to implementing any potential solutions.   

CV: EPIDEM is broken up into steps and principles. Let’s start with the steps. What are they and what do they stand for? 

YZ: The EPIDEM steps don’t necessarily have to be linear, but include the following: 

  • Exploration – includes exploring your own strengths and weaknesses as well as the local culture, context, and available resources.  

  • Promotion – Identifying and promoting solutions by defining the goal and identifying stakeholders, their motivations, and opportunities for solution building. 

  • Implementation and Documentation – Ensures your solution will be well received and successful. 

  • Evaluation and Modification – Evaluate the project’s success through both qualitative and quantitative measures, and make additional modifications as needed.  

CV: What are EPIDEM’s principles?  

YZ: EPIDEM underlying principles are in all other quality improvement models as well. These are derived from my life experiences, public policy education, and universal principles seen in quality improvement. I break them down into six key principles: 

  • Good intentions are not good enough—understand the local culture, context, and resources.  

  • Set worthwhile goals—establish meaningful goals and measures. 

  • Understand processes and systems—evaluate systems and simplify processes. 

  • Go for the high yield—prioritize problem players and interventions. 

  • It doesn’t count unless you can measure it—measure at baseline and with any changes. 

  • Your job is never done—adopt a culture of continuous improvement. 

CV: Why is QI important in pathology? How does it differ from quality assurance (QA) and quality control (QC) in the lab?  

YZ: Quality Assurance and Quality Improvement are very different. QA is a systematic process for ensuring the product you are offering meets Quality Control (QC) standards. I think of QA as the program or a management plan, whereas QC is the actual procedure for measuring against a standard. It is inspecting for errors and defects. In the laboratory, we do this by measuring things like turnaround time and regular “QC checks.” Are we in compliance or out of compliance? In range or out of range?  

QA is more reactive or even retrospective. In contrast, Quality Improvement is proactive and prospective—a mindset of continuous quality improvement. QI works in conjunction with QA and QC but rather than looking exclusively at numbers and finding defects, it is a way of thinking that values the system, teamwork, and views errors as opportunities for learning. 

If you work in healthcare, QI is our job. Our job is to do our job and do it better. It enables laboratory professionals to assess and explore the culture and contextual factors that are in place, analyze current problems, anticipate future problems, and brainstorm solutions with others.   

CV: Where should people go if they are interested in learning more about EPIDEM?  

YZ: There is a published EPIDEM guide in Laboratory Medicine. To illustrate the widely applicable nature of EPIDEM, in Table 3, I describe using the EPIDEM model to catch a gopher in my backyard. This comical illustration is always a hit when I give live presentations. The EPIDEM model is also featured in the ASCP Center for Quality and Patient Safety’s online self-directed Continuous Quality Improvement course, which is available on-demand through the ASCP website. 

It can also be helpful to see how EPIDEM has been applied by others. Since it’s free to use, I don’t know of every institution or laboratory that has used it. I do have readers reach out to me. A pathologist from Chennai Area, India, used EPIDEM to implement a new method for HCV testing in their hospital.  

In an online chapter in Pathology Outlines, I describe EPIDEM model along with additional examples of EPIDEM. There are several published articles as well. For example, the OU Molecular Pathology lab successfully utilized EPIDEM to improve the ordering of BCR-ABL1 tests and diagnosing Acute Promyelocytic Leukeamia, through focused educational efforts, validation of laboratory tests, and modification of clinical workflow.   

Authors at Emory used EPIDEM to implement a check list to exclude pregnancy in a high-risk teen clinic. A doctorate student in nursing at Southern Illinois University used EPIDEM as the conceptual framework to implement standardized electronic order sets in the intensive care units. Authors at Texas Tech University Health Sciences Center recommended the EPIDEM model for laboratories to respond to the COVID pandemic. 

CV: What is your ongoing goal for EPIDEM? 

YZ: My goal has always been to make the world a better place. As pathologists and laboratorians, our sphere of influence is the laboratory, but everybody – all members of the healthcare team – have their own unique ways of improving patient care. Let’s democratize QI for greater fairness, access, and equity in healthcare. Let’s create an EPIDEMic of healthcare providers who are working together and who are qualified and capable of QI to improve patient care.  

To read more on EPIDEM, visit  

Corey Whelan

Patient Advocate and Freelance Writer