Evidence-based Health care

The trend of using science more Diligently as a tool has far-reaching implications for the profession.

Sep 1st, 2004
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by Carol Jahn, RDH, MS

"The whole of science is nothing more than a refinement of everyday thinking."
— Albert Einstein

The concept of using science to make decisions is not new. In fact, whether you graduated five months ago or 25 years ago, most of us were taught this basic tenet in dental hygiene school. So, why is evidence-based health care (EBHC) now receiving so much attention? The medical professions — both doctors and nurses — have embraced EBHC as a way to improve decision-making and ultimately patient outcomes.1 The endorsement of this approach has made EBHC the standard for healthcare professions in the United States and other countries.2 Both the American Dental Hygienists' Association (ADHA) and the American Dental Association (ADA) have policy statements on EBHC. They are highlighted in Table 1.

The currently recognized definition of evidence-based healthcare is: "integration of best research evidence with clinical expertise and patient values."2

According to the father of EBHC, David Sackett, MD, "When these three elements are integrated, clinicians and patients form a diagnostic and therapeutic alliance which optimizes clinical outcomes and quality of life."2

"The great enemy of the truth is very often not the lie — deliberate, contrived, and dishonest ... but the myth — persistent, persuasive, and unrealistic."
— John F. Kennedy

What this means is that evidence is not just used to help the practitioner make good decisions about patient care, but that educating the patient on the evidence about treatments, drugs, and devices can help them embrace better decisions about what is right for them.

Perhaps, because the name emphasizes "evidence," many misinterpret or reject EBHC because they mistakenly believe the concept emphasizes research findings over experience. It does not. The definition of EBHC contains three equally important components:1

• Best research evidence
• Clinical expertise
• Patient values

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To arrive at the best decision, all three must be taken into consideration. Failing to do so is like probing but not recording bleeding or having current X-rays. The value of each is limited without putting all three into context.

Evidence is most effectively implemented via clinical expertise. Rarely do studies provide absolutes or mandates. Instead, most give information about the potential of the therapy or device.3 In most clinical trials, the subjects are healthy individuals. In practice, patients smoke, have diabetes, or a host of other medical complications that may impact the treatment outcome.

For example, a full-mouth disinfection protocol may seem to be a good way to treat the periodontal infection. But if the patient has Type 1 diabetes, recently received an insulin pump, reports frequent episodes of hypoglycemia, and has concerns about proper eating after back-to-back procedures, then a more traditional approach may be needed.

However, you cannot implement what you do not know. The practitioner bears the responsibility for knowing what type of evidence, if any, exists to support the procedures or products that are recommended. While it is largely recognized that only about 15 to 25 percent of procedures are based on evidence, it is important to know which ones are evidence-based and to make efforts to practice within that realm when evidence does exist.4

In contrast, the emphasis on experience — such as "it works in my hands, or for my patients" — may provide practitioners with a false sense of security about certain practices or procedures. Expectation has been shown to play a large role in perception. In other words, we seek information to confirm our ideas; anything that deviates from that is thought to be an aberration.5

For example, a recent trend has been to recommend a solution of diluted bleach for home irrigation. When the patient returns in a few months with much improvement in periodontal health, the improvement is often attributed to the bleach solution rather than the process of irrigation. In actuality, based on evidence, it is irrigation — regardless of the agent used — that is most likely responsible for the improvement, rather than the bleach solution.6 While experience does play an important role in practice, recognizing the inherent bias and ensuing limitations of our own experiences is worthwhile.

Along with "it works in my hands" is the concept "I know what is best for my patients." Yet, it is impossible for practitioners to fully acknowledge, let alone comprehend, the value system driving patients' decision-making. Previously, when scientific literature was available only to healthcare providers, patients had little choice but to rely on the clinician's judgment. Today, patients have nearly the same access to information as practitioners, positioning them to be active "consumers" in health-care decisions.

For example, many of the new local delivery and host modulation drugs have been directly advertised to consumers in several different medias. The Institute of Medicine recommends a "patient-centered" approach, noting that the patient's sense of control and perceived quality of life are favorably impacted by involvement in their care.7 Despite the fact that there will always be patients who either do not want to be a part of the decision process or those who fail to act on the decision made, educating the patient on current evidence, providing input from clinical experience, along with acknowledging patient preference, is key to EBHC.

"Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passions, they cannot alter the state of facts and evidence."
— John Adams

Better decision-making and improved patient outcomes are the oft-cited goals of EBHC. Yet, ironically, no evidence from randomized clinical trials currently exists to document improved patient outcomes, and it is likely that none ever will. Practical (sample size, blinding, follow-up) and ethical (withholding access to a proven therapy) issues make this difficult. On the other hand, it is well established that individuals who receive evidence-based therapies, such as those who get aspirin therapy after a stroke, fare better than those who do not.1 Likewise, the use of evidence can also protect patients, such as the discovery that hormone replacement therapy was more detrimental than beneficial to the overall health of postmenopausal women.

Better decision-making is a critical element in improving patient outcomes. While it is true that science has always been a component of clinical decisions, the science used was not always current or applied appropriately.

For example, most recognize scaling and root planing as the primary interventive therapy in treating the periodontal infection. Yet, some still carry out the procedure in a gross scale/fine scale format (a technique taught more than 20 years ago) instead of the currently accepted standard of quadrant/half mouth scalings.

Additionally, in the past, practitioners significantly relied on colleagues or the "key opinion leader" who spoke at continuing education courses and wrote articles and blindly accepted their opinion of "the right thing to do."1 Today, most practitioners recognize that it is important for opinions to be backed up with solid fact. This applies to continuing education courses as well as journal articles.

Adding the objective to the subjective brings balance to the decision-making process. Science is not always perfect but it does provide a benchmark. Without science, we would not have had the widespread practice of water fluoridation. Experience is fickle; some professionals grow from year to year while others refuse to progress. But experience provides most of us with a frame of reference. Without experience, we may still believe that every patient will use dental floss and we might neglect to introduce other effective interdental aids. Listening to our patients may sometimes take more time than we have scheduled. But listening to them provides us with clues of how we can best help them. Without patient input, it would be impossible to tell whether the cause of pain was the tooth, bruxism, or a sinus condition.

"This is what learning is. You suddenly understand something you have understood all your life but in a new way."
— Doris Lessing

Learning to practice EBHC is challenging and a life-long process. There are many skill-based elements — such as learning to search, locate, and evaluate literature — that are required for practicing EBHC; not all can be addressed in this article. See Table 1 and Table 2, as well as the May 2003 issue of RDH9, for additional resources. Practicing with a focus on EBHC can improve the workplace as well as individual patient care. EBHC can be applied at many levels — when evaluating treatments for patients, in helping educate patients on the best treatment for them, and in driving changes in office policy or systems that may affect overall patient care.

The evidence of smoking and its ill effects on periodontal health provide excellent examples of the impact EBHC has on multiple levels. On the practitioner level, in developing a treatment plan for a missing molar, generally both a bridge and an implant may be considered. However, if the patient is a heavy smoker, the implant may not be preferred since research has shown that smokers are at an increased risk for implant failure. On the patient level, a patient who learns that the recommended periodontal therapy will only be half as effective as it could be because of smoking may opt to delay treatment and quit smoking first. On the office level, information that smoking is responsible for at least 50 percent of all periodontal disease may drive the decision to incorporate smoking cessation information into the treatment plans of all patients who smoke.8

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The practice of EBHC has the potential to improve the workplace for dental hygienists. When job-seeking, knowing the evidence that supports certain procedures and protocols can help the hygienist ask the "right" questions and avoid offices that may not be in line with current practices. EBHC can be a tool in resolving conflicts; when opinions differ, evidence rather than power or position can be the deciding factor. Using evidence as the foundation, office protocols, diagnostic and treatment procedures, and product recommendations can be standardized and calibrated so that every staff member operates in the same format and supports each other's efforts.

"An education isn't how much you have committed to memory, or even how much you know. It's being able to differentiate between what you do know and what you don't."
— Anatole France

The practice of EBHC is not as simple as replacing one brand of product for another. It is more like losing weight — where constant commitment and personal change is required. To help your patients get the most benefit from EBHC, Dr. Sackett recommends the adoption of several personal goals:1

• Develop a mastery of the clinical skills of patient interviewing, health-history taking, and the physical exam. Without these, you cannot formulate a dental hygiene diagnosis or integrate patient values and expectations into the decision process.

• Embrace continuous, lifelong, self-directed learning. We live in the information age so without this, you will quickly become out-of-date.

• Maintain humility. Without it, you will never see the need for self-improvement and miss out on the advances taking place around you.

• Be enthusiastic. Change is going to happen regardless of the desire for it. It's better to enjoy the process than go "kicking and screaming."

The drive to practice evidence-based care in your office may not originate with the dentist-employer. That leadership role may need to be assumed by the dental hygienist. EBHC provides dental hygiene and dental hygienists a way to further develop professionally. It can lead to greater credibility and stature with all the stakeholders in dental hygiene: employers, patients, colleagues, public health departments, government agencies, and leaders to name a few. As difficult and overwhelming as EBHC may seem, it is a journey worth taking.

Resources for EBHC


Journal of Evidence-based Dental Practice, www.mosby.com/ jebdp, or (800) 654-2452; $69 per year

Evidence-based Dentistry, www.nature.com/ebd, or (800) 747-3187; $56 per year


Evidence-based Medicine: How to Practice and Teach EBM, Sackett D, Straus S, Richardson WS, Rosenberg W, Haynes RB (authors)

Achieving Evidence-Based Practice: A Handbook for Practitioners, Hamer S, Collinson G (editors)

• Evidence-Based Clinical Practice: Concepts and Approaches, Geyman JP, Deyo RA, Ramsey SD (editors)

Carol Jahn, RDH, MS is the educational programs manager for Waterpik Technologies where she designs multimedia educational programs for dental professionals. She provides continuing education programs in the areas of periodontics, patient compliance, and diabetes. Carol may be reached by phone at (800) 525-2020 or by e-mail at cjahn@waterpik .com.

1. Sackett DL et al. Evidence-based medicine: How to practice and teach EBM. 2000. London: Churchill Livingstone.
2. Ismail AI, Bader JD. Evidence-based dentistry in clinical practice. JADA 2004; 135: 78-83.
3. Jaeschke R et al. Evidence-based health care as a model for decision-making. J Evid Base Dent Pract 2004; 4:4-7.
4. Reekie D. The future of dentistry - the evidence-revolution. Br Dent J 1998;184:262-263.
5. Palmer J, Brice A. Information sourcing. In Hamer & Collinson (Eds) Achieving evidence-based practice: A handbook for practitioners. 1999 (1st ed. pp. 61-83) London: Bailliere Tindall.
6. Jahn C. Evidence for self-care products- Part II: Therapeutic mouthrinses and home irrigation. J Prac Hyg 2004;13:21-25.
7. Ponte PR et al. Making patient-centered care come alive: Achieving full integration of the patient's perspective. JONA 2003;33:82-90.
8. Johnson GK, Hill M. Start of the art review: Cigarette smoking and the periodontal patient. J Periodontol 2004;75:196-209.
9. Bowen DM, Forrest JL. Solving puzzling clinical questions. RDH 2003;23:3440,100.

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