title: Reliability of pulse waveform separation analysis: effects of posture and fasting.
abstract: Oscillometric pulse wave analysis devices enable, with relative simplicity and objectivity, the measurement of central hemodynamic parameters. The important parameters are central blood pressures and indices of arterial wave reflection, including wave separation analysis (backward pressure component Pb and reflection magnitude). This study sought to determine whether the measurement precision (between-day reliability) of Pb and reflection magnitude: exceeds the criterion for acceptable reliability; and is affected by posture (supine, seated) and fasting state.
  
  
  
  Twenty healthy adults (50% female, 27.9 years, 24.2 kg/m) were tested on six different mornings: 3 days fasted, 3 days nonfasted condition. On each occasion, participants were tested in supine and seated postures. Oscillometric pressure waveforms were recorded on the left upper arm.
  
  
  
  The criterion intra-class correlation coefficient value of 0.75 was exceeded for Pb (0.76) and reflection magnitude (0.77) when participants were assessed under the combined supine-fasted condition. The intra-class correlation coefficient was lowest for Pb in seated-nonfasted condition (0.57), and lowest for reflection magnitude in the seated-fasted condition (0.56). For Pb, the smallest detectible change that must be exceeded in order for a significant change to occur in an individual was 2.5 mmHg, and for reflection magnitude, the smallest detectable change was 8.5%.
  
  
  
  Assessments of Pb and reflection magnitude are as follows: exceed the criterion for acceptable reliability; and are most reliable when participants are fasted in a supine position. The demonstrated reliability suggests sufficient precision to detect clinically meaningful changes in reflection magnitude and Pb.
authors.affiliation: aDepartment of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina bSchool of Kinesiology, University of Southern Mississippi, Hattiesburg, Mississippi, USA cSchool of Sport and Exercise, University of Gloucestershire, Gloucester dDepartment of Sport & Exercise, University of Winchester eFaculty of Health Sciences, University of Southampton, Hants, UK fDepartment of Health and Physical Activity, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Lee
authors.initials: L
authors.lastname: Stoner
authors.forename: Daniel
authors.initials: D
authors.lastname: Credeur
authors.forename: Simon
authors.initials: S
authors.lastname: Fryer
authors.forename: James
authors.initials: J
authors.lastname: Faulkner
authors.forename: Danielle
authors.initials: D
authors.lastname: Lambrick
authors.forename: Bethany Barone
authors.initials: BB
authors.lastname: Gibbs
mesh_terms: D000328:Adult; D001794:Blood Pressure; D005215:Fasting / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009991:Oscillometry; D011187:Posture / Q000502:physiology*; D063177:Pulse Wave Analysis; D015203:Reproducibility of Results