Interobserver agreement in reading tuberculin tests
Guerra, M.; García de Blas, F.; Sanz, M.T.; Morales, M.C.; Pose, B.
Enfermedades Infecciosas y Microbiologia Clinica 11(10): 531-535
1993
ISSN/ISBN: 0213-005X PMID: 8142502 Document Number: 411496
The aim of the study was to evaluate the variability between four observers in the reading of the tuberculin test (TT). The study was carried out in the Centro de Salud Mendiguchía Carriche (Madrid) 72 subjects. By direct inspection, four observers read tuberculin determination (skin induration) independently in each subject. To assess variability, the kappa index (K) was calculated. On considering the variable as a dichotomous one, with a cut-off point of 5 mm was 0.88; and of 10 mm, 0.78. Upon considering the index as qualitative in four categories the kappa index in 0 mm was 0.89; in 1-4 mm, 0.24; in 5-9 mm, 0.40 and greater than 9 mm, 0.79. In eight of the subjects studied, the variability observed in reading the test had conditioned further different clinico-epidemiologic attitudes. The degree of concordance when reading TT is significantly lower at the 1-4 mm and 5-9 mm intervals.