Melanoma coverage and data quality

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Degree of coverage and completeness

All patients in Norway with melanoma must be included in the registry. 

All doctors who provide health care to patients with cancer are obliged to report to the Cancer Registry. This includes reporting to the quality register for melanoma. Melanoma is treated at all the country's hospitals, and all hospitals report to the Cancer Registry.

The coverage of clinical reports has increased in recent years, with the exception of last year, when we published the results for the first time before summer. Many departments have done a lot of work in previous years during the summer months and this helped to influence the result. Some enterprises report low year after year, which is worrying.

The Cancer Registry's basic registry contains information on 100 % of all patients with melanoma of the skin. The coverage rate for extended excision of skin in 2022 is 78.5 percent. One of the registry's quality objectives is a coverage rate of at least 80%. We are close to this, and we believe that part of the reason why we do not reach the target is because the hospitals have had shorter deadlines for reporting over the past two years. We therefore hope this will turn around and pick up again gradually now that the circular calendar has been turned.

Various measures to improve the degree of coverage have yielded results, particularly through the establishment of contact persons at the various hospitals. This will continue to be a main focus for the Melanoma Registry, as we see it taking time to establish good reporting routines at the various hospitals.

The degree of coverage of clinical reports for each hospital is specified in the annual report (Norwegian only).

Data quality

Quality assurance of data is done as an integral part of the coding and registration process. In addition, the following examples help to ensure data quality in the Cancer Registry:

  • Several independent sources report information
  • The information is reported at several points in the course of the disease
  • The Cancer Registry's employees have unique expertise in coding cancer cases in accordance with the Cancer Registry's own code book and international coding systems 
  • IT systems have rules and barriers for illogical combinations, incorrect information and more  
  • The Cancer Registry of Norway conducts analyses and control runs that reveal inconsistency in the data 
  • Data extraction for researchers makes it possible to check a smaller data set of information that can reveal individual errors (e.g. incorrect entry of hospital codes) or systematic differences due to different interpretations of coding systems and rules