Patient-reported outcomes in idiopathic pulmonary fibrosis research

Abstract

Patient-reported outcomes (PROs) include questionnaires or surveys that ask patients for their perceptions about things like symptoms they are experiencing or quality of life. For incurable, morbid, life-shortening conditions like idiopathic pulmonary fibrosis (IPF), PROs are particularly germane: They elucidate for clinicians and researchers what it is like for patients to live with such a disease, and they may detect important treatment effects not captured by other metrics (eg, pulmonary physiology). However, a relative paucity of research on PROs in IPF has left significant knowledge gaps in this area and contributed to the timidity investigators have about using PROs as prominent outcomes in IPF drug trials. Additional research on existing instruments is needed to establish or bolster their basic psychometric properties in IPF. When PROs are used as end points in therapeutic trials, analyzing PRO response data can be challenging, but these challenges can be overcome with a transparent, thoughtful, and sophisticated statistical approach. In this article, we discuss some of the basics of PRO assessment, existing knowledge gaps in IPF-related PRO research, and the potential usefulness of using PROs in IPF trials and conclude by offering specific recommendations for an approach to analyzing repeated-measures PRO data from IPF trials.

Figure 1.

Graph of subjects in one arm of a trial grouped on number of follow-up visits. All subjects in the arm have complete data for the baseline visit. Subjects in group 1 have complete data for each of the three follow-up visits (3 mo, 6 mo, and 12 mo). Subjects in group 2 dropped out after the 6-mo visit; they have complete data for the 3-mo and 6-mo visits but no data for the 12-mo visit. Subjects in group 3 dropped out after the 3-mo visit; they have complete data for the 3-mo visit but no data for the 6-mo or 12-mo visits.