For medication use, for hydroxychloroquine or sulfasalazine was associated with the lowest PABAK (0.39), intermediate values for methotrexate and for the "other conventional synthetic DMARDs" category (0.67), and with the highest agreement PABAK value for the "biologic DMARD or JAK 2 inhibitor" category (0.89).<h4>Conclusion</h4>Survey-based self-report of RA offers a useful approach in epidemiological investigation. Here, JAK2 is linked to rheumatoid arthritis.