The Power of Reliable Evidence

Changing medical culture and providing care providers and patients with needed information, thereby achieving quality, value, and truly informed consent in healthcare


By Michael E. Stuart MD, and Sheri Ann Strite
Delfini Group LLC

We are in a healthcare misinformation crisis. It is well-documented, yet little known, and has caused waste and a multitude of harms including thousands of preventable deaths. This crisis is due to a failure to educate healthcare professionals in requirements for trustable and useful information to inform decisions about medical interventions. To illustrate the seriousness of this failure, a typically missed question in our critical appraisal pre-test assesses awareness of the need for a comparison group in an efficacy study. Without one, how would you know a condition wasn't self-limiting? Reliable and useful medical science is needed to understand causality and probability of benefit or harm from medical interventions. Yet published medical science is often unreliable, misleading or reported so poorly that reliability is unknown. We are not protected from this problem by the best medical journals, the most prestigious investigators and institutions, or even the FDA.

Case in point: Over a four-year period, an estimated 60,000 patients in the US died and another 140,000 had heart attacks [1]— unlikely to have happened had their physicians understood how relative risk reduction can mislead by sounding very large compared to absolute values or natural frequencies. Yet another example: An estimated 63,000 patients in the US died preventable deaths [2] they might not have had their cardiologists understood the importance of randomization in studies attempting to establish cause and effect.

Through our research and teaching and evidence-based facilitation work, we have seen the transformative power of evidence to make vital changes in the quality of patient care when evidence-based principles are adopted and critical appraisal of the medical literature is embraced. For medical interventions, reliable and clinically useful evidence is the only pathway to truly informed consent, patient-centered care, quality patient care, and value. Importantly, understanding what constitutes reliable medical evidence and its importance can also create positive cultural and behavior change for healthcare systems and providers, leading to positive outcomes.

Below, using case studies, we illustrate how evidence-based QI activities can accomplish important tasks including positively changing the organizational culture to better serve patients and reduce waste.

Case Study 1: "There is good evidence that…" In a major company, the pharmacy and therapeutics committee used skilled non-physician staff to assess study validity, but committee decision-making frequently broke down when physicians, unfamiliar with critical appraisal, participated. Subspecialists’ opinions, offered in the guise of "evidence" with unsupported claims, often trumped sound evidence. Remedies included training, transparency in committee materials, and just-in-time teaching.

Result: A dramatic shift to discussions that were centered on the quality of evidence, causing greater participation of all members, and a greater number of evidence-based decisions.


Case Study 2: "The Evidence-based Machine!" Where we worked for many years, Mike turned his continuing medical education (CME) department into an evidence-based machine, adopting evidence-based methods, including inspiring and supporting clinical improvement projects and the development of clinical guidelines. This resulted in a major turn toward more informed decision-making based on reliable evidence and more complete information for providers and patients.Evidence-based outputs were then also used to assess impacts of medical practice change; create implementation, measurement and feedback plans; and develop communication aids.

Result: Improvement in quality, patient-centered care and value, and important contributions to the national healthcare discussion.


Case Study 3: "How to Make Evidence-Based Awareness Cultural & Use Evidence to Close Quality Gaps" One major medical group had an evidence-savvy leadership, but wanted to create an evidence-based culture. After basic training in critical appraisal, we recommended creating clinical guideline and quality improvement teams based on good evidence-based practices. Two major quality and cost gaps concerned managing chronic kidney disease (CKD). Effective decision support materials for managing CKD in primary care were needed along with a system change to improve the timing of referrals of CKD patients to nephrology. The ongoing problem was primary care physicians were referring patients to nephrology too early and too late. Inappropriately early referrals resulted in long wait times for nephrology appointment times; inappropriately late referrals led to irreversible renal damage in CKD patients. From experience, we knew the power of evidence-based clinical quality improvement through the route of guideline activities. A team was formed including primary care physicians (PCPs), nephrologists, a nephrology nutritionist, a renal pharmacist, and additional individuals experienced in critical appraisal. The project leaders played a critical role in designing, conducting, and evaluating the project. They communicated with leadership, assisted in obtaining resources, and helped us conduct the meetings which we facilitated [3]. Gaps were closed by increasing appropriate management of low-risk CKD patients by PCPs and timely referral of higher-risk patients to nephrologists. Final guideline products included:

  • Evidence summary critiques;
  • Evidence synthesis statements;Guideline recommendations and notes;1-pager of key points for patients and clinicians;
  • Algorithms with links allowing test or drug ordering at decision points;
  • Use of electronic decision-support system (E-consults between primary care and nephrologists);
  • and,Nephrologists assigned each day to review CKD patient records to determine which patients required management by their PCPs.

Result: Success was demonstrated by the impact on nephrology referrals, increased utilization of renin-angiotensin system blockers, increased appropriate laboratory testing, excellent receptivity by PCPs, and improved clinical care.


Case Study 4: "Now We Are All Talking To Each Other…" In this same medical group, there were differing points of view among the various specialties about the optimal approach to venous thromboembolism (VTE) prophylaxis for patients undergoing total hip replacement (THR) surgery and total knee replacement (TKR) surgery. There had been gridlock for so long that everyone just stopped talking about VTE prophylaxis.The problem (quality gap) was that there was significant uncertainty about the comparative effectiveness and safety of various agents in reducing clinically significant morbidity and mortality from thromboembolism or deep vein thrombosis in these surgeries. With resources and support from leadership, an evidence-based clinical guideline group was formed (orthopedists, hospitalists, pharmacists, nurses, and ourselves as evidence-based experts) to address the significant uncertainty by answering key clinical questions. We trained team members in basic critical appraisal, and all reviewed the medical evidence for reliability and clinical usefulness. The medical evidence synthesis was the linchpin for improved clinical care through the development of an evidence-based guideline. Equally important was the improvement in the local culture.
Result: At the end of this project, team members and colleagues in their departments were comfortable with the guideline recommendations, and communications between specialties improved [4].

Patients deserve better. Patients cannot give "informed consent" to medical interventions without reliable and useful information along with sufficient information about choices. The only way to overcome this is through awareness and knowledge of the importance of the right evidence, how to find it, and how to apply it. We need to change the nature of the conversation between providers and patients and the information provided to patients. In each of our examples, positive cultural change, improved patient care and value were driven by the power of evidence. Important ingredients for success included basic training in critical appraisal; evidence converted into usable information, decision and action tools; and, effective implementation. Taking these approaches, not only do patients win—we all win. We are all patients.


  1. Graham Natural News:
  2. Delfini estimates based on Echt DS, Liebson PR, Mitchell LB, Peters RW, Obias-Manno D, Barker AH, Arensberg D, Baker A, Friedman L, Greene HL, et al. Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial. N Engl J Med. 1991 Mar 21;324(12):781-8. PubMed PMID: 1900101
  3. Guideline & Health Care Quality Improvement Project Initiative—Nephrology Chronic Kidney Disease Project & Clinical Guideline:
  4. Guideline & Quality Improvement Project Initiative—Deep Vein Thrombosis (DVT)/Venous Thromboembolism (VTE) Project: