This document includes extracted information from 30 reviewed articles that investigated a causal relationship between exposure to antibiotics and the occurrence of asthma. For all 30 articles we formulated a theoretical design, that is also included in this document. This is part of a PhD-project that is investigating whether different approaches to study design (with specific interest in the formulation and reporting of a theoretical design) have an influence on study results. After registration of this document no changes were made, and the authors of the articles were contacted with questions concerning theoretical design. This is done with the aim of afterwards comparing our own formulated theoretical design, with what is reported to us afterwards by the authors.