The Janus material

 

The Janus samples originate from three different sources. In the 1970s–90s, a number of population-based health surveys for monitoring risk factors for cardiovascular diseases, were performed in Norway. About 90% of the Janus donors were recruited from five of those health surveys. Approximately 10% of the Janus cohort members origin from Red Cross blood donors living in Oslo and the surroundings. A small proportion of the samples (n ∼ 3 500) in the cohort are from donors that entered the cohort with a pre-diagnostic sample at one time point, were later diagnosed with cancer and donated a new diagnostic sample. For this subgroup, both pre-and post-diagnostic samples from the same individuals are available. See the table below for details. 

 

Characteristics Men Women Total
Total donors included in the cohort 166137 152491 318628
Average age at enrolment (years) 41 41 -
Number of individuals by sample origin      

- Health Examination donors (Oslo 1, The Age 40 program Oslo, The Norwegian Counties Study, The Age 40 program all counties and TROFINN)

146222 134898 281120
- Red Cross Blood donors 15079 13811 28890
Number of donors by number of sample collection time points      
Health examination donors      
                      1 118707 108067 226774
                      2 17524 16082 33606
                      3 9457 10117 19574
                      4 534 632 1166
Red Cross Blood donors      
                      1 5213 5971 11184
                      2 3066 2940 6006
                      3 1929 1620 3549
                     4 4871 3280 8151

 

 

Geographical distribution of sample collection in the Janus Serum Bank

 

From: Cohort Profile: The Janus Serum Bank Cohort in Norway Int J Epidemiol. 2016;46(2):403-404g. doi:10.1093/ije/dyw027 Int J Epidemiol