title: Evaluating intratester reliability of manual masking of plantar pressure measurements associated with chronic gout.
abstract: BACKGROUND
  Plantar pressure measurements are commonly used to evaluate foot function in chronic musculoskeletal conditions. However, manually identifying anatomical landmarks is a source of measurement error and can produce unreliable data. The aim of this study was to evaluate intratester reliability associated with manual masking of plantar pressure measurements in patients with gout.
  
  
  METHODS
  Twenty-five patients with chronic gout (mean disease duration, 22 years) were recruited from rheumatology outpatient clinics. Patients were excluded if they were experiencing an acute gout flare at the time of assessment, had lower-limb amputation, or had diabetes mellitus. Manual masking of peak plantar pressures and pressure-time integrals under ten regions of the foot were undertaken on two occasions on the same day using an in-shoe pressure measurement system. Test-retest reliability was assessed by using intraclass correlation coefficients, SEM, 95% limits of agreement, and minimal detectable change.
  
  
  RESULTS
  Mean peak pressure intraclass correlation coefficients ranged from 0.92 to 0.97, with SEM of 8% to 14%. The 95% limits of agreement ranged from-150.3 to 133.5 kPa, and the minimal detectable change ranged from 30.8 to 80.6 kPa. For pressure-time integrals, intraclass correlation coefficients were 0.86 to 0.94, and SEM were 5% to 29%, with the greater errors observed under the toes. The 95% limits of agreement ranged from -48.5 to 48.8 kPa/sec, and the minimal detectable change ranged from 6.8 to 21.0 kPa/sec.
  
  
  CONCLUSIONS
  These findings provide clinicians with information confirming the errors associated with manual masking of plantar pressure measurements in patients with gout.
authors.affiliation: School of Podiatry, AUT University, Auckland, New Zealand. krome@aut.ac.nz
authors.forename: Keith
authors.initials: K
authors.lastname: Rome
authors.forename: David George
authors.initials: DG
authors.lastname: Survepalli
authors.forename: Maria
authors.initials: M
authors.lastname: Lobo
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.forename: Fiona
authors.initials: F
authors.lastname: McQueen
authors.forename: Peter J
authors.initials: PJ
authors.lastname: McNair
mesh_terms: D000368:Aged; D001696:Biomechanical Phenomena; D002908:Chronic Disease; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006073:Gout / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011312:Pressure; D015203:Reproducibility of Results