<|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. patient and institutional outcome data are from the bmc2 database, which is governed by confidentiality agreements between bmc2 and the participating institutions and is not available. de-identified survey data are available by request from the corresponding author.<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>