<|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: baseline data for this study are available from the publicly released nhanes 19992002 which can be found at centers for disease control and prevention. nhanes 1999-2000 public data release file documentation (available from: http://www.cdc.gov/nchs/data/nhanes/nhanes_99_00/general_data_release_doc.pdf); centers for disease control and prevention. nhanes 2001-2002 public data general release file documentation (available from: http://www.cdc.gov/nchs/data/nhanes/nhanes_01_02/general_data_release_doc.pdf). however, these datasets were linked to mortality and morbidity data that are only accessible from the national center for health statistics, research data center with special permission from the nchs ethics review board due to the sensitivity of the information. all this is described in the manuscript and also in the following reference: centers for disease control and prevention. description of nchs-cms medicare linkage (available from: http://www.cdc.gov/nchs/data/datalinkage/description_of_nchs_cms_medicare_linkage_final.pdf).<|eot_id|><|start_header_id|>assistant<|end_header_id|>

yes<|eot_id|>