Here is a recap of the stories that appeared last week at Science-Based Medicine, a multi-author skeptical blog that separates the science from the woo in medicine.
Antidepressants and Effect Size (Harriet Hall) http://www.sciencebasedmedicine.org/index.php/antidepressants-and-effect-size/ Half of all antidepressant trials are negative, but many negative studies are never published. Looking at data from all trials, two researchers came to opposite conclusions based on a different understanding of “effect size.” Kirsch concluded that antidepressants were no better than placebo, while Turner showed that they were consistently effective.
Behavior and Public Health – To Nudge or Legislate (Steven Novella) http://www.sciencebasedmedicine.org/index.php/behavior-and-public-health-to-nudge-or-legislate/Lifestyle choices like smoking, weight control, and exercise are important to health, but it is difficult to change behavior. Individual counseling is only modestly successful. Public health measures reach the entire population but interfere with individual freedoms; “nudge” strategies have been proposed to influence without coercion. Any proposed measures should be based on science.
Salt: More confirmation bias for your preferred narrative (Scott Gavura) http://www.sciencebasedmedicine.org/index.php/salt-more-confirmation-bias-for-your-preferred-narrative/ Dietary salt is associated with high blood pressure; but dietary interventions have not been shown to lower the risk of heart attacks, strokes, or death. The long-term benefits of population-level interventions have not been established. Pending better data, a conservative approach is reasonable.
Dummy Medicines, Dummy Doctors, and a Dummy Degree, Part 1: a Curious Editorial Choice for the New England Journal of Medicine (Kimball Atwood)http://www.sciencebasedmedicine.org/index.php/dummy-medicines-dummy-doctors-dummy-degree-part-1/ A new study compared albuterol, placebo, acupuncture, and no treatment for asthma. All interventions produced similar subjective improvements, but only albuterol achieved objective improvement in lung function. The accompanying misguided editorial argued for any CAM treatment that makes people feel better, but thinking they are better when there is no objective improvement could have fatal consequences.
Asthma, placebo, and how not to kill your patients (Peter Lipson) http://www.sciencebasedmedicine.org/index.php/asthma-placebo-and-how-not-to-kill-your-patients/ The study described in the previous article by Dr. Atwood demonstrates that “placebo effect” is not the same as a real treatment, that real treatment always includes whatever benefit placebo provides, and that placebo is mostly an effect on subjective rather than objective measures of health. The study’s rationale and ethics are questionable. No good clinician would consider treating an asthmatic with placebo, since it could lead to debility and death.