title: Determination of prostatic volume with transrectal ultrasound: A study of intra-observer and interobserver variation.
abstract: OBJECTIVE
  We assessed the intra-observer and interobserver variation in measurements of prostatic volume using transrectal ultrasound.
  
  
  METHODS
  Two volume estimations were performed by 1 observer in 40 patients and by 2 observers in 75.
  
  
  RESULTS
  Mean prostatic volumes measured ranged from 18.9 to 87.0 ml. (median 39.8) for 1 observer and from 15.5 to 95.4 ml. (median 42.4) for 2 observers. The mean difference plus or minus standard deviation and limits of agreement between the paired volume estimations were 0.1 +/- 3.3 ml. and -6.5 +/- 6.7 ml., respectively, for 1 observer, and -0.3 +/- 5.3 ml and -10.9 to 10.3 ml., respectively, for 2 observers. The mean difference was 9.8% for 2 observers. The mean difference was 9.8% for 2 observers compared to 4.6% for 1.
  
  
  CONCLUSIONS
  The results show that there is considerable variation in repeated measurements of prostatic volume and the variation is greatest for 2 observers compared to 1 observer.
authors.affiliation: Bristol Urological Institute, Southmead Hospital and Department of Social Medicine, Bristol, United Kingdom.
authors.forename: T S
authors.initials: TS
authors.lastname: Bates
authors.forename: J M
authors.initials: JM
authors.lastname: Reynard
authors.forename: T J
authors.initials: TJ
authors.lastname: Peters
authors.forename: J C
authors.initials: JC
authors.lastname: Gingell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D015588:Observer Variation; D011467:Prostate / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D012007:Rectum; D014463:Ultrasonography