Thomas M. Cascino, Vallerie V. McLaughlin, Caroline R. Richardson, Nilofar Behbahani-Nejad, Victor M. Moles, Scott H. Visovatti, Elizabeth A. Jackson
European Respiratory Journal 2019 53: 1900028; DOI: 10.1183/13993003.00028-2019
Pulmonary arterial hypertension (PAH) is a progressive, non-curable disease with significant associated comorbidity, including reduced exercise capacity  and poor health-related quality of life (HRQoL) . Exercise capacity is frequently measured using the 6-min walk test (6MWT) . The 6MWT is easy to perform and correlates with disease severity and HRQoL . However, the 6MWT has limitations such as the need for a clinic visit to perform it  and ceiling effects which reduce the sensitivity to changes among patients .
Conflict of interest: T.M. Cascino reports grants from National Institutes of Health and from University of Michigan Frankel Cardiovascular Center, during the conduct of the study.
Conflict of interest: V.V. McLaughlin reports personal fees from Actelion Pharmaceuticals US, Inc., Bayer, Gilead Sciences, Inc., Medtronic, Merck, St. Jude Medical and United Therapeutics Corporation, and grants from Actelion Pharmaceuticals US, Inc., Arena, Bayer and Sonovie (University of Michigan received research funding), all outside the submitted work.
Conflict of interest: C.R. Richardson has nothing to disclose.
Conflict of interest: N. Behbahani-Nejad has nothing to disclose.
Conflict of interest: V.M. Moles has nothing to disclose.
Conflict of interest: S.H. Visovatti has nothing to disclose.
Conflict of interest: E.A. Jackson has nothing to disclose.
Support statement: This study was funded by a Michigan Medicine Frankel Cardiovascular Center Micro Grant and National Institutes of Health T32 postdoctoral research training grant (T32-HL007853). Funding information for this article has been deposited with the Crossref Funder Registry.