Supplemental materials for study "Impact of the methotrexate co-prescription on the persistence of TNF inhibitors in psoriasis: a cohort study on the French National Health Data System"
Description
This supplemental material provides additional methodological details, definitions, and results supporting the main analysis. Data Source: Describes the French national health data system (SNDS), and approvals for study. Marginal Structural Models (MSMs) with Inverse Probability Treatment Weighting (IPTW): Provides a detailed explanation of the statistical modeling framework used to estimate the causal effect of concomitant methotrexate (MTX) on TNFi persistence, including model specification, weight construction, stabilization, and truncation procedures. Supplemental Tables I–VI: Table I: Lists the ATC codes and definitions used to identify medication exposures. Table II: Describes algorithms for identifying comorbidities and related diagnoses from administrative data. Table III: Summarizes baseline characteristics of the study population across MTX exposure levels. Table IV: Presents detailed distributions of continuous and categorical MTX exposure across dosing regimens and calculation methods over trimesters. Table V: Reports results from sensitivity analyses assessing the robustness of the main findings under alternative definitions of MTX exposure. Table VI: Provides subgroup analyses evaluating the impact of concomitant MTX use on adalimumab persistence. Supplemental Figure 1: Displays a directed acyclic graph (DAG) illustrating the hypothesized relationships among biologic persistence, concomitant MTX use, and time-varying confounders.