How to apply for biological material and data from the Janus serum bank

On these pages you will find useful information on how to apply for access to biological material and data from the Janus serum bank
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Example for Study Design

The most widely used study design in the Janus biobank is the nested case-control design that selects controls from the same source population as for the cases.

The controls are selected from the Janus cohort members who are still disease-free at the time a case occurs. The cases are identified by linking the personal identification number in the biobank to the cancer registry. For each case, a specified number of matched controls are selected randomly among all those eligible at the time of the diagnosis of the case.

Matching of case and control is usually at an individual level and common matching criteria are gender, age, county, storage time and cohort. The matching of cases and controls according to time of blood draw, is recommended in order to minimize the impact of preanalytical handling, storage, and lifestyle effects. The Janus cohort represents the general population but also contains a subgroup of red Cross blood donors, that are a selected group of the population (e.g. they have been selected to not have any blood-borne diseases).We therefore recommend matching population-based cases to population-based controls, and blood donor cases to blood donor controls.

In a biobank, there will always be a trade-off between the need for saving biological material from rare cases for future use, and the need to match controls from the entire cohort to avoid selection bias. We assume that when the access to eligible controls is almost unlimited for a project, the selection bias will be negligible.


The table shows a proposed list of selection criteria in Janus projects.






Criteria for being a case

  • All cancers of specific site according to criteria developed by the Cancer Registry
  • Specific time period
  • Allow melanoma skin cancer prior to diagnosis 
  • Blood draw minimum one month before diagnosis to ensure that blood draw was made prior to treatment and to minimize biochemical effects caused by a soon-to-be-diagnosed cancer




Criteria for being a control

  • Alive and resident in Norway at date of diagnosis of case (ensuring follow-up for the same length of time as the case)
  • Free of cancer at the time of diagnosis of the case except for non-melanoma skin cancer (should be the same exclusion criteria used as for the cases).
  • Allow common cancers after date of diagnosis of case, but exclude controls with rare cancers to conserve valuable samples for later studies



Matching criteria

  • Age at blood draw typically differ no more than +/- 1 year from age of case at blood draw
  • Date of blood draw typically differ no more than +/- 3 months from data of blood draw of case
  • Same sex as case.
  • Blood draw in same county