RT Journal Article
SR Electronic
T1 Agreement of classification of COPD patients' physical activity with two activity monitors
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 1478
VO 42
IS Suppl 57
A1 Heleen Demeyer
A1 Roberto Rabinovich
A1 Susan Loh
A1 Yogini Raste
A1 Nick Hopkinson
A1 Zafiris Louvaris
A1 Iannis Vogiatzis
A1 Corina De Jong
A1 Tys Van der Molen
A1 Elena Gimeno-Santos
A1 Solange Rohou
A1 Damijan Erzen
A1 Karoly Kulich
A1 Niklas Karlsson
A1 Thierry Troosters
A1 Judith Garcia Aymerich
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/1478.abstract
AB RationaleIt is unclear whether different activity monitors provide similar classification of physical activity (PA) in patients with COPD.AimTo test whether similar PA classification of patients would be obtained when using 2 valid activity monitors.MethodsWe assessed PA for 4 weeks with Actigraph [(ACT: Steps and vector magnitude units (VMU)] and Dynaport [DAM: Steps, Movement intensity (MI), VMU] activity monitor in 236 COPD patients (FEV1 57±20%pred; 6MWD 430±125m) from 5 European centers resulting in 6776 patient-days.ResultsACT and DAM had respectively 11% and 6% missing patient-days and 11% and 12% patient-days had less than 8h of assessment. Steps per day recorded on ACT (mean±SD: 4248±2740) were lower than DAM (4767±2859, p<0.001). Similar concepts from DAM and ACT correlated very highly (R=0.91 VMU to 0.93 Steps). PA levels were converted to deciles in order to verify whether patients would also be classified in similar activity deciles with both monitors. For steps, 85% of patient-days were classified within 1 decile difference with both monitors [weighted κ 0.76 95%CI 0.75-0.77]. For VMU these values were 76% [weighted κ 0.69 95%CI 0.68-0.70]. Changes from week 1 to 4 were also tracked similarly by both monitors.ConclusionsThe PA values recorded on both monitors differed by a small, but statistically significant amount. Classification of patients in deciles renders very similar results with both ACT and DAM.