A recent nested case-control study based on a French national health insurance system database reported a significant association between thyroid cancer and GLP1 receptor agonist use (hazard ratio 1.46, 95% confidence interval 1.23 to 1.74).7 However, the comparator in that study was non-use of GLP1 receptor agonists, rather than an active comparator; exposure groups might have been misaligned on important baseline characteristics, potentially leading to confounding. The gene discussed is GLP1R; the disease is thyroid gland carcinoma.