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Eligibility requires existing participation in GDS and availability for four consecutive study days.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Interventions<\/jats:title>\n                    <jats:p>Participants underwent four IC measurements per day on four consecutive days, totalling 16 measurements per device. On each study day, two measurements with both devices, Vyntus CPX and Vmax Encore 29N, were performed in randomised order. Postcalorimetric gas calibration with normalisation was applied after each measurement.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary outcome measures<\/jats:title>\n                    <jats:p>Reliability of respiratory quotient (RQ) and resting energy expenditure (REE), as assessed from the coefficient of variation (CV) and 95% CIs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Device comparison showed minor differences in CV (95%\u2009CI) for carbon dioxide production (VCO\n                      <jats:sub>\u2082<\/jats:sub>\n                      ) (3.5% vs 5.3%; 95% CI \u22128.2% to 8.0%), oxygen consumption (VO\n                      <jats:sub>\u2082<\/jats:sub>\n                      ) (3.4% vs 5.7%; 95% CI \u22129.3% to 8.2%), RQ (3.6% vs 2.3%; 95% CI \u22123.5% to 3.7%) and REE (3.1% vs 5.6%; 95% CI \u22128.4% to 7.8%). Postcalorimetric calibration did not consistently affect RQ or REE.\u2003\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Vyntus CPX provides reliable IC measurements comparable to Vmax Encore 29N and may serve as a suitable replacement in clinical settings.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      ClinicalTrials.gov identifier:\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT01055093\">NCT01055093<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  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