ARE INTERPRETATIONS OF VIDEO DEFECOGRAPHIES RELIABLE AND REPRODUCIBLE

Video defecography is a dynamic investigation which can influence surg ical decision making in constipated patients. A study was therefore un dertaken to assess the inter and intraobserver variability in video de fecography. Specifically, we sought to assess the interpretation of vi deo defecographies by a group of observers with the same training, gui delines and standards. To determine interobserver variation, four inde pendent observers, two blinded to the patient's history, reviewed 100 randomly sequenced video defecographies performed in constipated patie nts. The presence or absence of sigmoidocele, rectocele, intussuscepti on or prolapse was noted. Adequate or improper function of the puborec talis, anal canal opening, anorectal angle (ARA) and grade of emptying of the rectum were also assessed. Two weeks after the initial assessm ent, intraobserver variation was determined by a repeat blinded review of unlabelled randomly sequenced studies. The results of interobserve r accuracy for sigmoidoceles, rectoceles, intussusception, rectal prol apse, rectal emptying, opening of the anal canal, puborectalis contrac tion and straightening of the ARA and rectal emptying were 89.5%, 46.0 %, 87.5%, 97.5%, 86.5%, 88.5%, 83.0%, and 80.0%, respectively. The int raobserver variations were 88.5%, 83.8%, 80.5%, 94.5%, 77.0%, 84.8%, 8 0.5% and 85.5%, respectively. Prior knowledge of the patient's history did not significantly influence the outcome. In summery, video defeco graphy has an overall accuracy of 83.3% and as such is a valid tool in assessing constipated patients.