A recent model of quality-adjusted life year (QALY) analysis showed that a PGx strategy might be considered cost-effective with an incremental cost-effectiveness ratio (ICER) of EUR 60,000 per QALY when compared with no genetic testing for major depressive disorders; CYP2D6 was cost-effective with an ICER of around EUR 47,000 per QALY [7,42]. Here, CYP2D6 is linked to major depressive disorder.