title: Reliability study of measurements for lymphedema in breast cancer patients.
abstract: OBJECTIVE
  Water displacement, circumference measurement, and tissue tonometry are important methods to evaluate the status of lymphedemous limbs in breast cancer patients. The purpose of this study was to investigate the reliabilities, and define the limits for clinical change indicative of clinical improvement with respect to these three measures.
  
  
  METHODS
  Fourteen patients were recruited for water displacement and circumference measurement, and 17 for tissue resistance by tonometry. All had been treated for breast cancer and subsequently developed lymphedema. Two physical therapists conducted the measurements to determine intra- and interrater reliability.
  
  
  RESULTS
  All measures had fair to excellent reliability (water displacement and circumference measurement, intraclass correlation coefficient [ICC] >0.99, P < 0.05; tissue tonometry, 0.66 < ICC < 0.88, P < 0.05). There was no systematic change in the mean for any of the measures. The variation, as determined by standard error of measurement (SEM), SEM%, smallest real difference (SRD), and SRD% was greatest for tissue tonometry.
  
  
  CONCLUSIONS
  Water displacement and circumference measurement (but not tonometry) are reliable techniques for assessing lymphedema in clinical practice. The effect of modifying the tonometry protocol and increasing the amount of rater training should be studied to determine whether the reliability of this method can be improved.
authors.affiliation: School of Occupational Therapy, College of Medicine, National Taiwan University, Taiwan.
authors.forename: Yu-Wei
authors.initials: YW
authors.lastname: Chen
authors.forename: Han-Ju
authors.initials: HJ
authors.lastname: Tsai
authors.forename: Hsiu-Chuan
authors.initials: HC
authors.lastname: Hung
authors.forename: Jau-Yih
authors.initials: JY
authors.lastname: Tsauo
mesh_terms: D000368:Aged; D001132:Arm / Q000033:anatomy & histology*; D001837:Body Weights and Measures / Q000379:methods*; D001943:Breast Neoplasms / Q000150:complications*; D005260:Female; D006801:Humans; D008209:Lymphedema / Q000175:diagnosis* / Q000209:etiology; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity