Healthy Skepticism Library item: 19043

Warning: This library includes all items relevant to health product marketing that we are aware of regardless of quality. Often we do not agree with all or part of the contents.

Publication type: Journal Article

Schwartz LM, Woloshin S, Welch HG
Can patients interpret health information? An assessment of the medical data interpretation test.
Med Decis Making 2005; 25:(3):290-300
http://mdm.sagepub.com/content/25/3/290.long

Abstract:

OBJECTIVE: To establish the reliability/validity of an 18-item test of patients’ medical data interpretation skills.

DESIGN: Survey with retest after 2 weeks. Subjects. 178 people recruited from advertisements in local newspapers, an outpatient clinic, and a hospital open house.

RESULTS: The percentage of correct answers to individual items ranged from 20% to 87%, and medical data interpretation test scores (on a 0- 100 scale) were normally distributed (median 61.1, mean 61.0, range 6-94). Reliability was good (test-retest correlation=0.67, Cronbach’s alpha=0.71). Construct validity was supported in several ways. Higher scores were found among people with highest versus lowest numeracy (71 v. 36, P<0.001), highest quantitative literacy (65 v. 28, P<0.001), and highest education (69 v. 42, P=0.004). Scores for 15 physician experts also completing the survey were significantly higher than participants with other postgraduate degrees (mean score 89 v. 69, P<0.001).

CONCLUSION: The medical data interpretation test is a reliable and valid measure of the ability to interpret medical statistics.

Keywords:
Adult Aged Aged, 80 and over Data Interpretation, Statistical* Decision Making Educational Measurement Educational Status* Female Health Care Surveys Health Knowledge, Attitudes, Practice* Humans Information Services/utilization Male Middle Aged New Hampshire Patient Education as Topic/statistics & numerical data* Psychometrics/instrumentation* Questionnaires* Risk Assessment/statistics & numerical data* Risk Factors