<|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: participants were men who have sex with men, and the study questions included sensitive ones, such as sexual risk behaviors. furthermore, during the consent process, the authors notified participants that their data would only be used for research purposes. for these reasons, data cannot be made publicly available. however, data will be made available to researchers upon request. requests for the data, including the purpose of the study and the way that data will be used, etc. should be submitted to the ethics committee of the chinese university of hong kong for approval. readers may contact the first author (jing gu, gujing5@mail.sysu.edu.cn) or the corresponding author (joseph lau, jlau@cuhk.edu.hk) for information related to this study.<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>