Patients and medical statistics. Interest, confidence, and ability

People are increasingly presented with medical statistics. There are no existing measures to assess their level of interest or confidence in using medical statistics.

To develop 2 new measures, the STAT-interest and STAT-confidence scales, and assess their reliability and validity.

Survey with retest after approximately 2 weeks.

Two hundred and twenty-four people were recruited from advertisements in local newspapers, an outpatient clinic waiting area, and a hospital open house.

We developed and revised 5 items on interest in medical statistics and 3 on confidence understanding statistics.

Study participants were mostly college graduates (52%); 25% had a high school education or less. The mean age was 53 (range 20 to 84) years. Most paid attention to medical statistics (6% paid no attention). The mean (SD) STAT-interest score was 68 (17) and ranged from 15 to 100. Confidence in using statistics was also high: the mean (SD) STAT-confidence score was 65 (19) and ranged from 11 to 100. STAT-interest and STAT-confidence scores were moderately correlated (r=.36, P<.001). Both scales demonstrated good test-retest repeatability (r=.60, .62, respectively), internal consistency reliability (Cronbach's alpha=0.70 and 0.78), and usability (individual item nonresponse ranged from 0% to 1.3%). Scale scores correlated only weakly with scores on a medical data interpretation test (r=.15 and .26, respectively).

The STAT-interest and STAT-confidence scales are usable and reliable. Interest and confidence were only weakly related to the ability to actually use data.