title: Usefulness index in nonspecific abdominal pain--an aid in the diagnosis?
abstract: OBJECTIVE
  In 1990, Lavelle and Kanagaratnam introduced Usefulness Index (UI) test for assessment of usefulness of clinical observations. Although, nonspecific abdominal pain (NSAP) is the most common diagnosis among secondary care patients with acute abdominal pain, the efficiency of UI test is rarely considered in NSAP.
  
  
  METHODS
  In an extension of the World Organisation of Gastro-Enterology Research Committee (OMGE) acute abdominal pain study, 1333 patients presenting with acute abdominal pain were included in the study. The clinical signs (n = 14) and tests (n = 3) in each patient were recorded in detail, using a predefined structured data collection sheet, and the collected data were compared with the final diagnoses of the patients.
  
  
  RESULTS
  The most significant clinical tests and signs of NSAP in univariate analysis were (UI = Usefulness Index and RR = risk ratio): rigidity (UI = 0.36, RR = 32.2), rebound (UI = 0.33, RR = 6.3), guarding (UI = 0.25, RR = 4.9), Murphy's positive (UI = 0.13, 8.9), bowel sounds (UI = 0.12, RR = 3.3), and renal tenderness (UI = 0.12, RR = 2.2). The sensitivity of the doctors' initial decision in detecting NSAP was 0.70 with a specificity of 0.83 and with the UI = 0.37 and RR = 11.4.
  
  
  CONCLUSIONS
  The patients with negative test results in rigidity, rebound, guarding, Murphy's, and bowel sounds tended to be at risk for NSAP and in these patients the UI test could be an aid for clinician to differentiate NSAP from other causes of acute abdominal pain.
authors.affiliation: Department of Surgery, Kuopio University Hospital and School of Medicine, University of Eastern Finland, Kuopio, Finland. matti.eskelinen@kuh.fi
authors.forename: Matti
authors.initials: M
authors.lastname: Eskelinen
authors.forename: Pertti
authors.initials: P
authors.lastname: Lipponen
mesh_terms: D015746:Abdominal Pain / Q000175:diagnosis* / Q000209:etiology; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D003657:Decision Making; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010173:Palpation; D010808:Physical Examination; D011237:Predictive Value of Tests; D055815:Young Adult