Doctors often are whip-smart and highly confident in themselves. But that doesn't mean that they're not subject to outside influence of the right form. An example of that came this week by way of a study published in JAMA Internal Medicine that found that one of health care's biggest problems can be diminished a bit by something as simple as a signed letter hanging in an examination room.

Regular readers of H&HN Daily know that antibiotics are on the brink of becoming ineffective for certain bacterial infections, that the use of antibiotics in food is contributing to the problem and apparently television personality Jenny McCarthy is not going to take up the cause, as I suggested a while back.

The authors of the study point out that, despite clearly published guidelines for the diagnosis and treatment of acute respiratory infection and decades of requests to limit prescribing of antibiotics as well as clinical interventions to stop them, inappropriate use of antibiotics still exists in a major way.

U.S. adults receive 41.2 million antibiotic prescriptions for respiratory infections at a cost of $1.1 billion, according to the study.

"Half of these prescriptions are inappropriate, since they are prescribed to treat ARIs for which there is no evidence of benefit," the study authors wrote. They chalk it up to such things as "defensive prescribing," unawareness of diagnostic guidelines — such as those that would allow a clinician to accurately distinguish between pneumonia and acute bronchitis — patient demand, and workplace culture.

So the authors decided to see if the very simple nudge of asking clinicians to hang a signed, poster-sized letter indicating the doctors were committed to reducing the use of antibiotics would have any effect.

It did. Clinicians who signed the letter in the randomized trial, which was conducted in five Los Angeles clinics, saw a relatively sharp decrease in prescribing rates of antibiotics, falling to 33.7 percent from 42.8 percent. Those not signing the letter increased their prescription rate to 52.7 percent from 43.5 percent.

The authors wrote that the approach holds great promise, even if it doesn't solve the problem, and could eliminate 2.6 million unnecessary prescriptions costing $70 million if implemented nationwide. The bigger benefit would the slowing of the decline in effectiveness of antibiotics. The next step in my mind is coming up with a similar low-cost way to get the point across to patients that they don't always need an antibiotic. It would be reassuring to see some progress on this problem.