The ENIGMA‐OCD consortium has already demonstrated significant scientific relevance by increasing our understanding of the disorder. Large‐scale worldwide collaboration has also been relevant to thinking through more effective and efficient ways of doing science by bringing together data, expertise, and a critical mass of investigators. Regarding clinical significance, the machine learning analyses of morphological measures of the brain are not yet valuable diagnostically (Bruin et al., 2019), and we certainly do not need an MRI scan to diagnose OCD. However, performance is likely to improve with the inclusion of multimodal features from diffusion‐weighted and functional MRI. However, several important lessons with clinical relevance have emerged. One example is the unexpected, but robust finding that medication status and disease chronicity both have a marked impact on all brain measures analyzed to date. This has two direct implications: First, it emphasizes the importance of establishing longitudinal studies to examine the beneficial and potential harmful effects of medication on the developing brain and; second, the fact that disease chronicity is related to marked morphological alterations of the brain might provide additional incentive to
