A medical terminology achievement reading test (MART) administered to patients was developed for health care practitioners and researchers. In this study, 405 respondents from five populations (nursing home patients, college students, high school students, adult basic education students, and shopping mall customers) took both the MART and the Wide Range Achievement Test (WRAT). Cronbach's reliability test alpha indicated a high level (alpha = 0.98) of likelihood that the MART score is a good estimate of the true score (WRAT), and, therefore, reading ability. MART is designed to resemble a prescription label with its use of small print size, glossy cover, and medical terminology. This design allows practitioners and researchers to assess patients' inability to read the test. It is thought that its design and use of medical terminology makes the MART less threatening to patients than other literacy tests. Further studies of the MART in low-literate populations could determine whether this is true.