Casefinding or case ascertainment is the identification of all eligible cases to be included in the cancer registry database. Complete casefinding is necessary to ensure that cancer incidence rates are accurate. Both completeness and timeliness are evaluated based on contractual requirements.
The casefinding audits are performed by a qualified member from each SEER registry under the direction of NCI SEER personnel. Auditors create a mini abstract which contains the primary site and the casefinding source among other information.
- Selection of facilities
The selection of facilities audited is based on the number of cases available and the geographic distribution of the facilities within the region covered by the central registry. The facilities selected for the audit will be those that contribute a significant number of cases to the central registry. As a national program, NCI SEER must focus efforts and resources on factors that have the greatest impact on the central registry's data quality. The central registry has the responsibility of periodically auditing all facilities within their region.
- Hospital cases vs. non-hospital
Hospital pathology laboratories often review tissue from patients not seen in that hospital. These are what we call "non-hospital cases". NCI SEER chooses facilities with path labs that review tissue for non-hospital cases. This is another way to assess the central registry's ability to identify all eligible cases in their region.
When doing audits, SEER adheres to the two basic audit principles: auditing high quantity and high risk.
- Sites with the greatest frequency (e.g. for most registries, breast, lung, colon, prostate would comprise over 50% of the registry cases). If you can effect changes in data quality for these four sites, you are having the greatest effect on your database that you can achieve with a reasonable amount of resources.
- Facilities that contribute the greatest percent of cases to the central registry's database.
- A high risk for error (e.g. sites such as head and neck, hematopoietic diseases).
- Includes auditing for compliance with new rules.
- Newly reportable diseases. Since the identification and collection of these diseases is new to the registrars, there is a high risk for errors.
- We audit/study new rules and newly reportable cases in order to identify issues in these high risk categories early. It is important to test/audit for any problems and implement the appropriate solutions before the errors become ingrained