One of the underlying assumptions of placebo-controlled randomized trials is that the placebo effect is always constant; however, different types of placebo interventions may be associated with different responses. Meissner and coauthors investigated this question in a meta-analysis of 79 randomized clinical trials on migraine prophylaxis. Findings from univariate analyses showed that more patients responded with a significant reduction of attack frequency to sham acupuncture and sham surgery than to oral drug placebos. When controlling for possible confounders, only sham acupuncture and sham surgery were significantly associated with the placebo response. In an Editor’s Note, Redberg details the implications for future placebo-controlled studies.
Related Article, Editor’s Note
Little is known about the relationship between physicians’ diagnostic accuracy and their confidence in that accuracy. Meyer and coauthors conducted an experimental study in which internists diagnosed case vignettes of variable difficulty. Despite a large difference in diagnostic accuracy between easier and more difficult cases (55% vs 6%), the difference in confidence was relatively small and likely clinically insignificant. The relationship between diagnostic accuracy and confidence was worse for more difficult cases and characterized by overconfidence in accuracy. The findings suggest that physicians’ confidence may be relatively insensitive to diagnostic accuracy and case difficulty. An Invited Commentary from Dhaliwal accompanies this study and the study by Cook and coauthors.
Related Article, Invited Commentary
Answering clinical questions affects patient-care decisions and is important to continuous professional development, but the process of point-of-care learning is incompletely understood. Cook and coauthors surveyed focus groups involving 50 internal medicine and family medicine physicians from an academic medical center and community practices using a model characterized by 6 key decisions: whether to search, when to search, to search with the patient present or in a separate room, to use a human vs computer resource, how to select a specific resource, and when to stop. They found that time was the greatest barrier to learning, followed by patient complexity, information overload, and not knowing which resource to use. An Invited Commentary from Dhaliwal accompanies this study and the study by Meyer and coauthors.
Reducing methicillin-resistant Staphylococcus aureus (MRSA) in both health care and community settings continues to be a high priority for the Centers for Disease Control and Prevention, and estimating the burden of MRSA—how much is occurring, where it is happening, and how it is being spread—is essential for developing effective prevention programs and measuring their impact. In this study, Dantes and coauthors evaluated the most recent tracking data to estimate the number of invasive (life-threatening) MRSA infections that occurred in 2011. They found that 30 800 fewer serious MRSA infections occurred in all settings in 2011 compared with 2005 and more than 9000 fewer deaths occurred among individuals hospitalized with MRSA. They also found a 54% decline in serious MRSA infections occurring among patients during hospitalization between 2005 and 2011. While more invasive infections occurred among otherwise healthy persons in the community than among hospitalized persons, most infections still occurred among persons recently discharged from hospitals. Lowy considers the current state of MRSA in the United States in an Invited Commentary on this study and the study by Casey and coauthors.
The manure produced by livestock given feed with antibiotics contains antibiotic-resistant bacteria, resistance genes, and antibiotics and is subsequently applied to crop fields where it may put community members at risk for antibiotic-resistant infections. To estimate associations between individual-level exposure to swine and dairy/veal industrial agriculture and risk of methicillin-resistant Staphylococcus aureus (MRSA) infection, Casey and coauthors conducted a population-based nested case-control study in Pennsylvania. They selected patients with MRSA infection and skin and soft-tissue infection (without a history of MRSA) and frequency-matched controls from more than 450 000 primary care patients in the Geisinger Health System and estimated exposure by incorporating livestock number, crop field area, and manure volume into 2 exposure models. The results suggested that approximately 11% of community-associated MRSA and skin and soft-tissue infections in the study population could be attributed to crop field application of swine manure. Lowy considers the current state of MRSA in the United States in an Invited Commentary on this study and the study by Dantes and coauthors.
Federal legislation has reshaped observation status, shifting more observation care to hospital wards, yet limited data exist on how this practice has affected patients and institutions. Sheehy and coauthors undertook a descriptive study at an academic medical center, finding that 10.4% of 43 853 hospitalizations were observation stays, with 1 in 4 general medicine ward patients being observed as opposed to admitted as inpatients. While the Centers for Medicare & Medicaid Services states that observation care should typically conclude in under 24 hours, and in only “rare and exceptional cases” exceed 48 hours, in this study less than half of all observation care resolved in less than 24 hours and approximately 1 in 6 stayed longer than 48 hours. Wachter calls for reform to observation status policy in an Invited Commentary.
Continuing Medical Education
Highlights. JAMA Intern Med. 2013;173(21):1937-1939. doi:10.1001/jamainternmed.2013.6338