Author's Response to Reviews Report of Shanil Ebrahim Background – (revisions Fall into Category 1)

Revisions fall into category 2) Incomplete sentence – “five percent of all hospital admissions are at least possibly...” Authors: Sentence completed. Omit “very likely” from the first sentence of the conclusion in the abstract. Authors: Done. Add “lly” to statistical significant increase in the second sentence to the conclusion of the abstract. Authors: Done. Omit “a” from “a further tailoring of the ICD-10” in conclusion of the abstract. Authors: Done. Background – (Revisions fall into category 1) Replace all the semi-colons with commas in the third sentence. Authors: Done. Be consistent with referencing at the end of a sentence or in the middle of the sentence. Authors: Placed at the end of a sentence. The authors mention that a variety of monitoring systems have been developed and the oldest and most common one is the spontaneous reporting system. Reference this. Authors: Reference added. The authors should reference the use of databases from health insurers in the countries they listed. Authors: References added. What projects are the authors referring to for “the epidemiological projects” and what “well-defined research questions” are the authors talking about? Authors: We changed the wording. The background is incomplete. The authors did not give an adequate justification of why they are carrying out the study. Exploring evidence in previous literature would support this purpose. Authors: We add a justification as well as references. Methods – (Revisions falls into category 1) Incorrect use of quotations in the identification of relevant ICD-10-codes section Authors: Corrected. If using primary diagnosis and secondary diagnosis as proxies for drug-related hospital admissions and hospital acquired adverse drug events, the authors should either cite evidence that this is sufficient or provide justification. Authors: We add further information from the German coding standards that define the correct usage of primary and secondary diagnoses. The content from the methods section is sufficient. An elaboration of statistics is required as the readers are not able to comprehend of what exactly was analyzed.