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Scenario 3: When Lack of Evidence or Consensus Warrants More Informed Decision-making

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Making Informed Decisions for Better Health

Overview | Health Outcomes | EBM | Patient-centered Care | Informed Decisions | Examples | Talking to Your Doctor | Resources | Sources | Return to main article (use browser Back button)

Various factors can influence the decisions made and actions taken by patients and their healthcare practitioners regarding testing. No decision can be viewed as entirely clear-cut and the elements influencing decision-making can be seen as existing along a continuum among a spectrum of possibilities. Balancing these influences according to a given situation can be central to improving healthcare.

The following is the third set of examples in a series of three. These are the areas along the continuum of care where the available evidence for use of a test is not clear-cut or the significance of its use is disputed or questioned. In this situation, the patient-centered view may take precedence.

Example one Evidence for testing is unclear and there is no consensus; decision about testing is achieved through weighing pros and cons with healthcare practitioner (informed decision)
Test PSA
Desired outcomes Fewer deaths from prostate cancer, fewer unneeded biopsies and invasive procedures
Evidence Screening using PSA has not lowered death rates; false positive results in painful biopsies; when cancer is detected, there is currently no good way to determine if it is slow-growing or aggressive
Standard care No consensus
Patient considerations Some men will choose screening, others will not; those who choose screening and have positive result will have to make choices about biopsy to diagnose cancer, watchful waiting, and treatment; decisions based on how they view the risk: which is worse: knowing or not knowing?
Healthcare improvement Patient is in control of decision based on individual acceptance of risks; research is ongoing to find test or procedure that can differentiate between slow-growing and aggressive cancer

An example of a situation in which there is a lack of consensus on the available evidence is screening asymptomatic men for prostate cancer using the test for prostate-specific antigen (PSA). The evidence regarding this test consists of data from large, long-term studies that indicate that screening with PSA is no better than standard care in lowering death rates from prostate cancer. That, coupled with the possible harms from false-positive results and unnecessary, possibly painful follow-up procedures, have led some in the medical community to advise against the use of the test. In contrast, some other health experts say that this population-based evidence should not apply to individuals, that each patient, armed with facts on pros and cons of testing, should be allowed to make an informed decision. In this scenario, the decision to test or not can rest squarely with the patient. While some patients will welcome the autonomy, others may choose to rely on the advice of their healthcare practitioner and, in each situation, the level of risk that is acceptable to the patient enters into the picture.

Example two Some consensus on testing; decision for testing based on patient need
Test Breast cancer screening (mammography)
Desired outcomes Fewer deaths from breast cancer; fewer false positives and unnecessary follow-up procedures, such as biopsies
Evidence Some experts say, for women younger than 50, harms outweigh the benefits; others advise screening younger than 50 and more frequently than every two years
Standard care Some consensus; age 50 and older, test every two years
Patient considerations Some want to be screened regardless of advice in order to know whether or not they have cancer; others choose to wait until they are older and get screened less frequently to avoid false positives
Healthcare improvement Women have access to testing when they choose to undergo screening

For women who are considering breast cancer screening through the use of mammography, there is some consensus from healthcare professionals, but there are enough differences that women must consider their options carefully. The American Cancer Society and the American College of Obstetricians and Gynecologists recommend annual screening for those of average risk beginning at 40 years of age. However, the U.S. Preventive Services Task Force (USPSTF) says that for women at average risk and who are under age 50, the decision when to start regular screening mammography should be an individual one, taking into consideration such factors as a woman's risk tolerance. The USPSTF also recommends less frequent screening for women over age 50, advising that mammography be done every other year. While mammography can detect breast cancer in the earliest stages when it is most treatable, it can also lead to false-positive results and unnecessary follow-up procedures, including sometimes biopsies. Thus, a woman must decide for herself, with the help of her health practitioner, what her tolerances are for risk if she forgoes testing and possibly misses early cancer or undergoes testing and possibly gets a false-positive result.

Example three Evidence is insufficient at this time
Test High-sensitivity CRP (hs-CRP) for cardiovascular disease risk
Desired outcomes Lower risk of cardiovascular disease (CVD)
Evidence No current consensus exists on when to get tested; studies are ongoing to evaluate the role of hs-CRP in assessing a person's risk of CVD
Standard care Measuring blood hs-CRP may be useful in conjunction with other tests that are performed to assess risk of heart disease, such as a lipid profile, in apparently healthy people who don't have any of the traditional factors such as high blood pressure, high cholesterol level, or smoking
Patient considerations If studies have not yet proven that the test has value, patient may choose to forego testing even if health practitioner recommends it as providing additional risk information
Healthcare improvement Patients choose whether testing is worth the time and cost

The high-sensitivity CRP test detects low levels of inflammation in the body. It is promoted by some as a test for determining a person's risk level for CVD, heart attacks, and strokes. This is because it is now believed that a persistent low level of inflammation plays a major role in atheroslcerosis, the narrowing of blood vessels associated with cardiovascular disease. A number of risk factors have been linked to the development of CVD, but a significant number of people who have few or no identified risk factors will also develop CVD. This fact has lead researchers to look for additional risk factors that might be either causing CVD or that could be used to determine lifestyle changes and/or treatments that could reduce a person's risk of CVD. Studies have shown that measuring CRP with a highly sensitive assay can help identify the risk level for CVD in apparently healthy people. It is thought that normal but relatively high levels of CRP in otherwise healthy individuals can predict the future risk of a heart disease, even when cholesterol levels are within an acceptable range. Clinical trials that involve measuring hs-CRP levels are currently underway in an effort to better understand its role in cardiovascular events. These studies may eventually lead to guidelines on its use in screening and treatment decisions. Meanwhile, a healthcare practitioner may suggest the test as a means to provide additional information of an individual's risk, but a patient may choose to forego it until studies provide more evidence of its usefulness.