title: Reproducibility of colonic transit study in patients with chronic constipation.
abstract: OBJECTIVE
  Major therapeutic decisions are rendered based on a single colonic transit study. Therefore, the aim of this study was to assess the reproducibility of colonic transit time in patients with chronic constipation.
  
  
  METHODS
  Fifty-one patients with chronic idiopathic constipation were randomly selected to undergo two separate colonic transit tests. All clinical conditions, methodology, and patients' instructions were identical on both occasions. The gamma rate (linear correlation analysis) was undertaken between the first and second colonic transit times. Groups were divided according to the diagnoses of colonic inertia (slow-transit constipation), paradoxical puborectalis contraction, and chronic idiopathic constipation (normal-transit constipation).
  
  
  RESULTS
  In 35 of 51 patients (69 percent), the results were identical between the two studies; however, in 16 patients (31 percent), the results were disparate (gamma correlation coefficient = 0.53; P < 0.01). The specific correlation coefficients for patients with colonic inertia, paradoxical puborectalis contraction, and chronic idiopathic constipation were 0.12, 0.21, and 0.60 (P < 0.01), respectively. Moreover, the success rate of colectomy for colonic inertia was significantly higher in patients who underwent a repeat transit study confirming inertia than in patients who underwent colectomy based on a single study.
  
  
  CONCLUSIONS
  Overall, colonic transit time is reproducible in patients with chronic constipation. The correlation coefficient is best for patients with idiopathic constipation and worst for patients with colonic inertia. This new finding suggests that suboptimal surgical outcome may be attributable to inaccurate diagnosis. Because of this poor correlation coefficient, in patients with colonic inertia, consideration should be given to repeating the colonic transit study before colectomy to help secure the diagnosis and improve outcome.
authors.affiliation: Department of Colorectal Surgery, Cleveland Clinic Florida, Fort Lauderdale, Florida 33309-1743, USA.
authors.forename: Y S
authors.initials: YS
authors.lastname: Nam
authors.forename: A J
authors.initials: AJ
authors.lastname: Pikarsky
authors.forename: S D
authors.initials: SD
authors.lastname: Wexner
authors.forename: J J
authors.initials: JJ
authors.lastname: Singh
authors.forename: E G
authors.initials: EG
authors.lastname: Weiss
authors.forename: J J
authors.initials: JJ
authors.lastname: Nogueras
authors.forename: J S
authors.initials: JS
authors.lastname: Choi
authors.forename: Y H
authors.initials: YH
authors.lastname: Hwang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D003082:Colectomy; D003106:Colon / Q000503:physiopathology / Q000601:surgery; D003248:Constipation / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D003672:Defecation / Q000502:physiology; D003951:Diagnostic Errors; D005260:Female; D005772:Gastrointestinal Transit / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011897:Random Allocation; D015203:Reproducibility of Results; D016896:Treatment Outcome