I love the narrative in this new phenotype, @Patrick_Ryan! Straight to the point that I was mentioning yesterday during the office hours with @Gowtham_Rao!: clinical validity is of essence in cohort definitions. It is extremely useful and reassuring to run internal validation such as stability across data sources, and sub populations (calendar years, gender, etc) and it is just great and super useful to have packages like Phevaluator, cohort diagnostics, phoebe, etc to assess that. Next, we need to bring focus to the clinical side of our cohort definition systematically: is it capturing the clinical features that we are aiming to? It is awesome how you were able to estimate PPV in your MM phenotype without quitting Atlas by reviewing patient profiles, but I honestly miss the complete picture: how many true MM cases were actually not captured with your phenotype? I.e., how can we estimate the sensitivity of our cohort definitions? @Marcela shared with me some interesting comments on this line of thought that @Andrew and @schuemie posted some time ago in a forum thread. In fact, it was suggested oncology as a promising starting point for this to evolve in OHDSI. I Can’t wait for the next phenotype! 