Top 20 Research Studies of 2017 for Primary Care Physicians

Mark H. Ebell, MD, MS; Roland Grad, MD, MSc,


Am Fam Physician. 2018;97(9):581-588. 

In This Article

Abstract and Introduction


Based on systematic surveillance of more than 110 medical journals, 247 studies met criteria as POEMs (patient-oriented evidence that matters) in 2017. Members of the Canadian Medical Association identified 20 of these POEMs as most relevant to practice. This article reviews the clinical questions and bottom-line answers from these studies. Blood pressure should be measured after a period of rest, using a bare arm, and orthostatic blood pressure is more predictive when measured after one minute of standing rather than three minutes. Intensive blood pressure lowering results in cardiovascular benefits but also renal harms in high-risk patients with an average age of 68 years. The initiation of a statin for primary prevention does not reduce cardiovascular events in adults 65 years or older. Sterile gloves do not reduce the risk of infection for common outpatient skin procedures, and the preferred approach to managing onychomycosis is empiric oral terbinafine. Routine home glucose monitoring is not needed in patients with type 2 diabetes mellitus, and trying to achieve an A1C target level of 6.0% rather than 7.0% to 7.9% does not improve outcomes and may be harmful. Fasting blood glucose and A1C levels have limited accuracy for identifying glucose intolerance, and patients 65 years and older with thyroid-stimulating hormone levels between 4.6 and 10.0 mIU per mL should be rechecked before considering treatment. Gabapentin and pregabalin are not effective for acute or chronic low back pain, even in patients with sciatica. Physical therapy does not provide any additional benefit over usual care in patients with acute ankle sprain, and corticosteroid injections for knee osteoarthritis are ineffective and may damage cartilage. A two-question screening test can rule out depression in older adults; a large U.S. trial continued to find no benefit to prostate cancer screening; and clinicians need to be thoughtful about how they discuss recommendations to stop screening for cancer in older patients. Finally, ibuprofen, naproxen, and celecoxib have similar risks of adverse events, and continuous positive airway pressure in patients with obstructive sleep apnea does not reduce the risk of cardiovascular events.


The volume of studies published annually has expanded greatly in recent decades. For example, 6,762 studies were indexed as randomized controlled trials in PubMed in 1990, compared with 24,434 in 2015. It is increasingly difficult for primary care physicians, who have a broad scope of practice, to remain current with the most important new research. To address this issue, for more than 20 years, a group of clinicians who are experts in evidence-based medicine has systematically reviewed more than 110 English-language research journals to identify the evidence most likely to change primary care practice. The group includes experts in family medicine, pharmacology, hospital medicine, and women's health.[1,2]

The goal of the review process is to identify POEMs: patient-oriented evidence that matters. A POEM must report patient-oriented outcomes, such as improvement in symptoms, morbidity, or mortality; be free of important methodologic bias; and recommend a change in practice for many physicians. Adopting valid POEMs in clinical practice could therefore result in improved patient outcomes. Of more than 20,000 research studies published in 2017 in these journals, 247 met these criteria for validity, relevance, and practice change.

Since 2005, the Canadian Medical Association (CMA) has paid for a subscription to POEMs for all of its members. Each member has the option to receive the daily POEM by e-mail. When members read the POEM, they can also rate it with a validated tool called the Information Assessment Method. This tool addresses relevance to clinicians, cognitive impact, use in practice, and expected health benefits if that POEM is applied in practice.[3] For this article we identified the 20 POEMs that were rated highest for clinical relevance by CMA members in 2017. In the seventh installment of this annual series,[4–9] we summarize the clinical question and bottom-line answer for each of the top 20 research studies identified as POEMs, organized by topic and followed by a brief discussion. We also review the five most relevant practice guidelines. The full POEMs are available online at