PT - JOURNAL ARTICLE AU - Adam J.N. Raymakers AU - Mohsen Sadatsafavi AU - Don D. Sin AU - J. Mark FitzGerald AU - Carlo A. Marra AU - Larry D. Lynd TI - Avoiding immortal time bias in observational studies AID - 10.1183/13993003.02494-2019 DP - 2020 Mar 01 TA - European Respiratory Journal PG - 1902494 VI - 55 IP - 3 4099 - http://erj.ersjournals.com/content/55/3/1902494.short 4100 - http://erj.ersjournals.com/content/55/3/1902494.full SO - Eur Respir J2020 Mar 01; 55