The p factor and associations across partners, time, and generations: Commentary on Caspi et al. (2026)

Comments on the original article by Caspi et al. (see record 2026-80066-001). Drawing on both surveys and (primary and specialist care-assigned) register-based diagnoses, Caspi et al. displayed that the positive manifold among psychiatric conditions is present not only between individuals, but also across partners, time, and generations. To this impressive work, I add three comments. First, regarding intergenerational transdiagnostic transmission, our research group observed a similar pattern of results in a sample of three million Swedes linked to their parents, and that the results extended to school and labor market performance (Zhou et al., 2024). Second, regarding transdiagnostic patterns over time, Caspi et al. (2026) argued that most disorders eventually morph into different disorders. Third, although the observed transdiagnostic patterns across partners, time, and generations are consistent with an underlying p-factor, so are other models without a p-factor (Caspi & Moffitt, 2018). (PsycInfo Database Record (c) 2026 APA, all rights reserved).