<|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 do not own the data underlying this study. due to legal and ethical restrictions, the data are available upon request to interested researchers from dr. henrique barros (institute of public health, university of porto), pending ethical approval. further information can be found at the institute of public health website: http://ispup.up.pt/.<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>