Annually for 22 years, a team of clinicians has systematically reviewed English-language medical journals to identify original research most likely to change and improve primary care practice. The team includes experts in family medicine, pharmacology, hospital medicine, and women's health.^1,2

The goal of this process is to identify POEMs (patient-oriented evidence that matters). A POEM must report at least one patient-oriented outcome, such as improvement in symptoms, morbidity, or mortality. It should also be free of important methodologic bias, making the results valid and trustworthy. Finally, if applied in practice, the results would change what some physicians do by prompting them to adopt a new practice or discontinue an old one that has been shown to be ineffective or harmful. Adopting POEMs in clinical practice should improve patient outcomes. Of more than 20,000 research studies published in 2020 in the journals reviewed by the POEMs team, 306 met criteria for validity, relevance, and practice change. These POEMs are emailed daily to subscribers of Essential Evidence Plus (Wiley-Blackwell, Inc.).

The Canadian Medical Association purchases a POEMs subscription for its members, many of whom receive the daily POEM. As these physicians read a POEM, they can rate it using a validated questionnaire. This process is called the Information Assessment Method (https://www.mcgill.ca/iam). POEM ratings address the domains of clinical relevance, cognitive impact, use of this information in practice, and expected health benefits if that POEM is applied to a specific patient.^3,4 In 2020, each of the 306 daily POEMs was rated by an average of 1,230 physicians.

In this article, we present the 20 most clinically relevant POEMs as rated by Canadian Medical Association members in 2020. This is the 10th installment of our annual series (https://www.aafp.org/afp/toppoems). As we write this article, the pandemic rolls on. However, beyond COVID-19, our patients continue to face the usual (and unusual) health problems of everyday life. Thus, we summarize the clinical question and bottom-line answer for research studies identified as a top 20 POEM, organized by topic and followed by a brief discussion. This set of 20 POEMs includes the two most relevant practice guidelines of the year. The full POEMs are available online at https://www.aafp.org/afp/poems2020.

COVID-19

The year 2020 saw the emergence of SARS-CoV-2, a novel coronavirus that causes the COVID-19 illness, and 54 POEMs addressed the epidemiology, diagnosis, treatment, and prognosis of patients with COVID-19. Not surprisingly, the four most highly rated POEMs of the year and five in the top 20 provided evidence regarding preventive measures (Table 1).^5–10 These were published early in the pandemic and provided important evidence for family physicians to share with their patients.

The most highly rated POEM was originally published in 2015 and reissued in 2020 after the content was updated for COVID-19. The study was a large pragmatic trial in the United Kingdom that randomized participants to a brief online hand-washing intervention or usual care. Those who completed the intervention had fewer respiratory tract infections over the next four months (51% vs. 59%; P < .001; number needed to treat = 12).⁵

The next COVID-19 POEM was a Cochrane review.⁶ The authors reviewed the results of modeling studies of COVID-19 and previous coronavirus pandemics, as well as four observational studies. They concluded that quarantine measures are effective in slowing the spread of infection, especially when implemented early and in conjunction with other public health measures.

The third POEM summarized the results of two ecologic studies. The first compared COVID-19 incidence rates in eight Iowa counties that did not have stay-at-home orders with seven neighboring Illinois counties that had such orders in place.⁷ The second compared a Georgia county that implemented stay-at-home orders approximately two weeks before the rest of Georgia with seven surrounding counties.⁸ In both studies, earlier implementation of stay-at-home orders was associated with a lower incidence of COVID-19.

Another POEM summarized the results of one of the earliest studies to evaluate the effectiveness of different kinds of masks for preventing the spread of respiratory droplets.⁹ Using laser technology, 14 types of masks were evaluated. Gaiters and bandanas were essentially useless, polypropylene and surgical masks were much better, and N95 masks were best.