Voutilainen, A.; Virtanen, J. K.; Hantunen, S.; Nurmi, T.; Kokko, P.; Tuomainen, T.-P. Nonoptimal Follow-up Times Make It Difficult to Detect the Epidemiological Inverse Relationship Between 25-Hydroxyvitamin D and Lung Cancer. Biostatistics Research 2021, 1, 1-10.