Delayed hypersensitivity to tuberculin, total immunoglobulin E, specific sensitization, and atopic manifestation in longitudinally followed early Bacille Calmette-Guérin-vaccinated and nonvaccinated children.

Background: Bacille Calmette-Guérin (BCG) is a strong T helper 1 incentive and, thus, may contribute to a decreased risk of T helper 2-dependent atopic disease.

Objective: To investigate the natural course of specific immunoglobulin E (IgE) responses and atopic disease in BCG-vaccinated and nonvaccinated children.

Participants: Seven hundred seventy-four children from a prospectively followed birth cohort.

The (in)validity of sensitivity and specificity.

This paper is a legacy of the first author, and after her untimely death reconstructed by the second author as a tribute to Irene Guggenmoos's contribution to biostatistics. It discusses two different views on diagnostic testing: the classical view in which sensitivity and specificity of a diagnostic test are considered universal constants, and the more statistical point of view that focuses on predictive values. The differences between the two paradigms are outlined and practical examples are discussed to show that the familiar concepts of sensitivity and specificity must be handled with care and not used indiscriminately.

Effect of pre- and postnatal tobacco smoke exposure on specific sensitization to food and inhalant allergens during the first 3 years of life. Multicenter Allergy Study Group, Germany.

Background: The study aimed to assess the effect of pre- and postnatal tobacco smoke exposure on specific sensitization to food allergens and inhalant allergens during the first 3 years of life.

Methods: A total of 342 children of a prospective and observational birth cohort study on atopy (MAS) were included on the basis of a complete follow-up of specific IgE measurements at the ages of 1, 2, and 3 years with available questionnaire information about the parental smoking habit at birth, 18 months, and 3 years of age. Study children were grouped into four exposure categories representing in utero and postnatal environmental tobacco smoke (ETS) exposure, and according to the number of cigarettes smoked by the parents.

Long-lasting sensitization to food during the first two years precedes allergic airway disease. The MAS Study Group, Germany.

The purpose of the study was to investigate whether the duration of sensitization to food allergens during early childhood is related to later development of IgE mediated hypersensitivity to inhalant allergens and of allergic rhinitis and asthma in 5-year-old children and whether long-lasting food-sensitization may be used to predict subsequent allergic airway diseases. Five hundred and eight children of a prospective birth cohort study with available serum samples at one and two years of age were included and followed up until five years of age. Specific sensitization to food and inhalant allergens and the occurrence of subsequent allergic airway diseases were determined.

Kappa-like indices of observer agreement viewed from a latent class perspective.

It is common practice to assess consistency of diagnostic ratings in terms of 'agreement beyond chance'. To explore the interpretation of such a term we consider relevant statistical techniques such as Cohen's kappa and log-linear models for agreement on nominal ratings. We relate these approaches to a special latent class concept that decomposes observed ratings into a class of systematically consistent and a class of fortuitous ratings.