One of the key weaknesses of the "consumer-driven health plan" movement is that consumers have little access to quality information about individual doctors.
Now a team of researchers led by Dana Gelb Safran, a researcher at a health institute affiliated with Tufts-New England Medical Center in Boston, has published results of a study suggesting that quality evaluators can get reasonably reliable physician quality data from a collection of 45 completed patient satisfaction survey questionnaires and very reliable quality data from a collection of about 300 patient questionnaires.
The Safran paper, which deals only with patient satisfaction and not with measures of the technical quality of care, such as how likely comparable patients are to die or end up in the hospital, appears in the January issue of the Journal of General Internal Medicine.
The researchers drew on a sample of 13,000 adult patients of 215 "generalist physicians," or primary care doctors, at 67 practices in Massachusetts.
The researchers ended up with an average of 58 completed questionnaires per physicians. Questions asked about matters such as satisfaction with physician referrals and the politeness of patients' own doctors' office staff.
The researchers used a tool called the "Spearman Brown Prophecy Formula" to estimate roughly how well correlated the average patient response was for each satisfaction measure and about how many responses would be needed to get reliable results for each physician.
The researchers also used another statistical tool, the Central Limit Theorem, to estimate how many physicians might end up getting lower grades than they deserved.