<|begin_of_text|><|start_header_id|>system<|end_header_id|>

You are an expert at identifying data availability statements in scientific text. A data availability statement describes where research data can be found or how it can be accessed.<|eot_id|><|start_header_id|>user<|end_header_id|>

Determine if the following text contains a data availability statement. Answer with 'yes' or 'no'.

Text: the authors confirm that, for approved reasons, some access restrictions apply to the data underlying the findings. data are subject to national data protection laws and only available upon formal request. for kora f4 the steering committee (prof. dr. annette peters, helmholtz zentrum münchen, institute of epidemiology ii) needs to be contacted at www.helmholtz-muenchen.de/epi2 and of ship-trend at http://www.medizin.uni-greifswald.de/icm/transferstelle/.<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>