title: A scoring system for the prediction of choledocholithiasis: a prospective cohort study.
abstract: BACKGROUND
  Techniques for diagnosing choledocholithiasis pose significant morbidity and mortality risks.
  
  
  OBJECTIVE
  We aimed to develop and validate a clinical scoring system for predicting choledocholithiasis.
  
  
  METHODS
  Data from a prospectively maintained database of all patients with gallstones.
  
  
  METHODS
  Patients were admitted to the general surgery department of a military hospital.
  
  
  METHODS
  We enrolled consecutive patients with symptomatic gallstones, biliary pancreatitis, obstructive jaundice, or cholangitis, who subsequently underwent biochemical testing and ultrasonography. A predictive model was developed from a scoring system using their imaging and laboratory data. Endoscopic retrograde cholangiopancreatography (ERCP) or intraoperative cholangiography were used for confirmatory diagnoses. The predictive efficacy of the scoring system was validated using a retrospective cohort of 272 patients.
  
  
  METHODS
  Predictive accuracy of the scoring system.
  
  
  RESULTS
  We enrolled 155 patients in the development group. The common bile duct diameter, alkaline phosphatase of >=200 IU, elevated bilirubin levels, alanine transaminase of >=220 IU, and male age of >=50 years were significantly associated with choledocholithiasis and were included in the scoring system. Ninety-six patients (35%) had scores of >=8 (high risk), 86 patients (32%) had scores of 4-7 (intermediate risk), and 27 patients (10%) had scores of 1-3 (low risk). In the validation cohort, the positive predictive value for a score of >=8 was 91.7%, and the scoring system had an area under the curve of 0.896.
  
  
  CONCLUSIONS
  Scores of >=8 were strongly correlated with choledocholithiasis in the developmental and validation groups, which indicates that our scoring system may be useful for predicting the need for therapeutic ERCP. However, prospective validation in a large multicenter cohort is needed to fully understand the benefits of the system.
  
  
  CONCLUSIONS
  The retrospective validation cohort might have introduced selection and observational biases. The study may have been underpowered because of the sample size of the developmental cohort. The delay between admission and the time of ERCP theoretically may have increased the number of negative ERCP results, but our false negative rate for ERCP was consistent with the previously reported rates.
authors.affiliation: Dr. Bilal Omar Al-Jiffry, Taif University, Department of Surgery, College of Medicine and Medical Sciences, PO Box 888 Taif 21947, Saudi Arabia, jiffrybilal@hotmail.com.
authors.forename: Bilal O
authors.initials: BO
authors.lastname: Al-Jiffry
authors.forename: Samah
authors.initials: S
authors.lastname: Khayat
authors.forename: Elfatih
authors.initials: E
authors.lastname: Abdeen
authors.forename: Tasadooq
authors.initials: T
authors.lastname: Hussain
authors.forename: Mohammed
authors.initials: M
authors.lastname: Yassin
mesh_terms: D000328:Adult; D000367:Age Factors; D000410:Alanine Transaminase / Q000097:blood; D000469:Alkaline Phosphatase / Q000097:blood; D019540:Area Under Curve; D001663:Bilirubin / Q000097:blood; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods / Q000706:statistics & numerical data*; D002761:Cholangitis / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging; D042883:Choledocholithiasis / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology; D003135:Common Bile Duct / Q000000981:diagnostic imaging / Q000473:pathology; D016208:Databases, Factual; D005260:Female; D042882:Gallstones / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging; D006305:Health Status Indicators; D006801:Humans; D041781:Jaundice, Obstructive / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology; D012737:Sex Factors; D014463:Ultrasonography
chemical_list: D000410:Alanine Transaminase; D000469:Alkaline Phosphatase; D001663:Bilirubin