<|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 present data set contains longitudinal data of children under six years old. authorization from the the cnpd  comissão nacional de protecção de dados the portuguese data protection authority was given under the condition that data would not be freely available to other parties and countries. data are and will be available upon request to the principal investigator (antónio santos, asantos@ispa.pt).<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>