This dataset concerns the diagnostic accuracy of tests for HIV
infection. Four different tests (A, B,
C, and D) were applied to 428 high-risk patients. The
result from each test is either negative ("neg") or positive
("pos"). Yang and Becker (1997) applied latent-class analysis
to these data to estimate the sensitivity and specificity of these
tests in the absence of a gold standard.
hivtesta data frame with 9 rows and 5 variables:
Atest result from radioimmunoassay (RIA) utilizing recombinant agl21
Btest result from RIA utilizing purified HIV p24
Ctest result from RIA utilizing purified HIV gpl20
Dtest result from enzyme-linked immunosorbent assay
COUNTfrequency; number of patients exhibiting the given pattern of results