<|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 data discussed in this paper were obtained from the ebonyi state ministry of health in nigeria and the authors do not have the authority to make them publicly available. however, the data are available upon request by contacting dr. christian ezeora achi, director public health care and disease control, ministry of health, abakaliki, ebonyi state (achiezeora@gmail.com).<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>