IGF1 and hereditary endocrine growth disease: Future work should monitor IGF-1 changes in dried blood spots stored differently for years to enhance the reliability of QAMS samples for retrospective and longitudinal studies, especially for pediatric growth disorders (ICH E11, 2017; Maus et al., 2020; Motorykin et al., 2021; Moncrieffe et al., 2020; To et al., 2021).