The overall aim of the project was to evaluate the use of routinely collected animal based measures (ABMs) for an evaluation of the overall animal welfare in dairy cow herds. ABMs being able to detect worst adverse effects in relation to animal welfare were identified based on the existing literature and expert opinion. The validity and robustness of these ABMs were evaluated and cow mortality, somatic cell count and lameness were selected for further study. A number of factors of variation were selected using expert opinion and used in a model to collate routinely collected data from Italy, Belgium and Denmark on selected ABMs. The routinely collected data was uploaded to the Data Collection Framework platform at EFSA and the data management in this process was evaluated. Five research datasets from Italy, Belgium, Denmark and France including information on ABMs as well as a measure of 'overall animal welfare' at herd level were analysed to evaluate the association between the ABMs (individually or in combination) and overall welfare. The measure of 'overall animal welfare' were not the same for all datasets. Except from the Italian data, the association between the ABMs and the different overall welfare measures were generally weak. Likewise, combining more than one ABM only improved the prediction of the overall welfare in the Italian dataset. Analyses of the other datasets could not confirm this finding. Finally, suggestions for future recordings of ABMs not routinely collected at the moment were given with a special focus on lameness. In conclusion, the relationship between selected ABMs and overall welfare at the herd level is complex and still not sufficiently studied. Therefore, a system using routinely collected ABMs to predict the overall welfare at herd level in dairy herds does not seem realistic based on the results from the present study. The present document has been produced and adopted by the bodies identified above as author(s The present document has been produced and adopted by the bodies identified above as author(s). In accordance with Article 36 of Regulation (EC) No 178/2002, this task has been carried out exclusively by the author(s) in the context of a grant agreement between the European Food Safety Authority and the author(s). The present document is published complying with the transparency principle to which the Authority is subject. It cannot be considered as an output adopted by the Authority. The European Food Safety Authority reserves its rights, view and position as regards the issues addressed and the conclusions reached in the present document, without prejudice to the rights of the authors. SUMMARYThe European Food Safety Authority (EFSA) aims to establish a practical and validated basis for data collection of animal based measures (ABMs) for farmed animal species and consequent quantitative risk assessment of the welfare of target populations. Through a series of six integrated objectives this project evaluated the possibility to use routinely collected ABMs to pre...