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Overview of the Process for Obtaining the Data

The SEER-MHOS data are available to outside investigators for research purposes. Although personal identifiers for all patient and medical care providers have been removed from the SEER-MHOS data, there remains the remote risk of re-identification (given the large amount of data available). In light of the sensitive nature of the data, maintaining patient, hospital and health plan confidentiality is a primary concern of the National Cancer Institute (NCI), SEER, and the Centers for Medicare and Medicaid Services (CMS). Therefore, the SEER-MHOS data are not public use data files. Investigators are required to obtain approval in order to obtain the data. The primary purpose of the approval process is not to critique the methodology or merits of proposed projects, but to ensure the confidentiality of the patients and providers in SEER areas. Reviewers from NCI and SEER may comment, however, on aspects of the research plan that may affect project feasibility and scientific rigor. NCI will work with investigators requesting data files to balance their research needs with those of the individuals and institutions included in the data.

For reasons of confidentiality, selected variables are not routinely released on the SEER-MHOS files. These variables include the patient's Census tract identifier and ZIP code reported by SEER at the time of first cancer diagnosis, the ZIP code at the time of the MHOS survey, and the Managed Care Plan ID and Contract number. Selected 2000 Census data aggregated at the Census tract and ZIP code level are included in the file (see Data Dictionary documentation). However, the actual ZIP code and Census tract identifiers were removed. These aggregated variables have been slightly altered to prevent matching back to the Census data and identifying the actual Census tract or ZIP code. Please review the Privacy and Confidentiality Issues section for more information on these variables.

Once a data request has been approved and all appropriate documents are on file, IMS (NCI's programming contractor) will provide an invoice to the investigator to cover the costs of creating the requested data files (see Cost of Acquiring SEER-MHOS Data). In accordance with an NCI-IMS contractual agreement, IMS will begin processing data requests upon receipt of payment. IMS requires pre-payment of all invoices. Extracted files are sent in SAS Cport format. In order to ensure the security of the patient's information during transition of files, the data files will be encrypted using WinZip (256bit AES encryption) and password-protected. The data files will also be compressed using the GZIP compression utility. A program will be made available to unzip the files onto the user's PC in the directory that the user specifies. The PC must be equipped with Windows NT, Windows 95 or later. GUNZIP is necessary to unzip the files if using a UNIX or Linux machine.

Last Modified: 11 Apr 2014