%D 2021 %I NATURE RESEARCH %L discovery10131355 %P 1744-1758 %T Resource profile and user guide of the Polygenic Index Repository %O This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. %X Polygenic indexes (PGIs) are DNA-based predictors. Their value for research in many scientific disciplines is growing rapidly. As a resource for researchers, we used a consistent methodology to construct PGIs for 47 phenotypes in 11 datasets. To maximize the PGIs’ prediction accuracies, we constructed them using genome-wide association studies — some not previously published — from multiple data sources, including 23andMe and UK Biobank. We present a theoretical framework to help interpret analyses involving PGIs. A key insight is that a PGI can be understood as an unbiased but noisy measure of a latent variable we call the ‘additive SNP factor’. Regressions in which the true regressor is this factor but the PGI is used as its proxy therefore suffer from errors-in-variables bias. We derive an estimator that corrects for the bias, illustrate the correction, and make a Python tool for implementing it publicly available. %V 5 %A J Becker %A CAP Burik %A G Goldman %A N Wang %A H Jayashankar %A M Bennett %A DW Belsky %A RK Linner %A R Ahlskog %A A Kleinman %A DA Hinds %A A Caspi %A DL Corcoran %A TE Moffitt %A R Poulton %A K Sugden %A BS Williams %A KM Harris %A A Steptoe %A O Ajnakina %A L Milani %A T Esko %A WG Iacono %A M McGue %A PKE Magnusson %A TT Mallard %A KP Harden %A EM Tucker-Drob %A P Herd %A J Freese %A A Young %A JP Beauchamp %A P Koellinger %A S Oskarsson %A M Johannesson %A PM Visscher %A MN Meyer %A D Laibson %A D Cesarini %A DJ Benjamin %A P Turley %A A Okbay %K Behavioural genetics, Economics, Genome-wide association studies, Human behaviour %J Nature Human Behaviour