Clinically accessible tools for documenting the impact of #Orthostatic intolerance on symptoms and function in ME/cfs by Lee, Jihyun et al
"Clinical observations have indicated that hours of upright activity (HUA) reported by Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) patients correlated with orthostatic symptoms and impaired physical function. This study examined the relationship between HUA and orthostatic intolerance (OI)"