RT Book, Section A1 Simel, David L. A1 Rennie, Drummond SR Print(0) ID 3489515 T1 Pretest Probabilities and Likelihood Ratios for Clinical Findings T2 The Rational Clinical Examination: Evidence-Based Clinical Diagnosis YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071590303 LK jamaevidence.mhmedical.com/content.aspx?aid=3489515 RD 2024/09/16 AB Table Graphic Jump LocationPretest Probabilities and Likelihood Ratios for Clinical FindingsView Table||Download (.pdf)Pretest Probabilities and Likelihood Ratios for Clinical FindingsPrior ProbabilityTest/FindingLR+LR-Chapter 1: Primer on Precision and AccuracyChapter 2: Abdominal Aortic AneurysmOccur in 4% to 8% of older men. The prevalence in older women is less than 2%.Physical examination for aneurysm > 4.0 cm16 (8.6-29)0.51 (0.38-0.67)Physical examination for aneurysm > 3.0 cm12 (7.4-20)0.72 (0.65-0.81)Chapter 3: Abdominal BruitsApproximately 1% to 5% of the general population has renovascular disease. Approximately 20% of white patients with medical refractory hypertension have renal artery stenosis.Systolic-diastolic bruit39 (10-145)0.62 (0.49-0.73)Systolic bruit4.3 (2.3-8.0)0.52 (0.34-0.78)History of atherosclerotic disease2.2 (1.8-2.8)0.52 (0.40-0.66)Chapter 4: Problem Alcohol Drinking3 of 10 adults engage in risky drinking behaviors. In primary care clinics, the prevalence will be around 11% to 18%.(see Tables 4-12 and 4-13)AUDIT or AUDIT-C ≥ 86.8-12AUDIT or AUDIT-C ≤ 80.46-0.62(see Table 4-14)CAGE ≥ 13.4 (2.3-5.1)CAGE = 00.18 (0.11-0.29)(see Tables 4-15 and 4-16)TWEAK ≥ 2 or T-ACE ≥ 13.6-4.0TWEAK ≤ 1 or T-ACE = 00.12-0.15Chapter 5: Appendicitis, Adult25% for patients younger than 60, 5% for patients older than 60Alvarado score (≥7 is positive, see Table 5-5)3.1 (1.9-5.0)0.26 (0.19-0.35)Prior ProbabilityTest/FindingLR+LR-Chapter 6: AscitesLess than 1% for unselected population, 5% for general medical patientsSymptomsIncreased abdominal girth makes ascites more likely4.1 (2.3-4.7)Recent weight gain makes ascites more likely3.2 (1.7-6.2)Ankle swelling makes ascites more likely2.8 (1.8-4.3)No ankle swelling makes ascites less likely0.10 (0.01-0.67)No increase in abdominal gain makes ascites less likely0.17 (0.05-0.62)No recent weight gain makes ascites less likely0.42 (0.20-0.87)SignsFluid wave5.3 (2.9-9.5)Shifting dullness2.1 (1.6-2.9)Chapter 7: Low Back PainApproximately 85% of patients with back pain will not have a definitive diagnosis. Since 20-30% of asymptomatic patients have a herniated disc, this can be used as the prior probability for herniation.Sit-to-stand test for upper lumbar herniation26 (1.7-413)0.35 (0.22-0.56)Nocturnal pain for cancer-induced back pain1.7 (1.2-1.9)>0.17 (0.03-0.73)Crossed straight-leg herniation1.6-5.80.59-0.90Ipsilateral straight-leg raise for disk herniation0.99-2.00.04-0.50Chapter 8: Breast Cancer12% lifetime risk for US womenClinical breast examination11 (5.8-19)0.47 (0.40-0.56)Chapter 9: Carotid BruitSymptomatic patients: 10%-30% will have surgically amenable carotid stenosisAsymptomatic patients: 1%-10% probability for carotid stenosis in patients 60 years or older. 0.5% for patients 50 years of age to approximately 10% by age 90 years. For patients older than 65, 5% to 7% of women and 7% to 10% of men will have carotid stenosis of 50% or higher. 1% to 2.3% of women and 1% to 4.1% of men older than 60 will have stenosis of 75% to 99%.Symptomatic PatientsIpsilateral bruit3.0 (1.3-7.1)No ipsilateral bruit0.49 (0.36-0.67)Asymptomatic PatientsIpsilateral bruit4.0-10No ipsilateral bruitUncertainChapter 10: Carpal Tunnel7% probability of hand symptoms compatible with CTSPresence of Tinel or Phalen signs~ 1Absence of Tinel or Phalen signs~ 1Prior ProbabilityTest/FindingLR+LR-Chapter 11: Central Venous PressureApproximately 10% patients with a left ventricular ejection fraction 35% or less at baseline had an elevated CVP.It is estimated that 10% to 20% of patients previously diagnosed as having low ejection fraction had elevated CVP.Abdominojugular reflex for detecting high CVP4.4 (1.8-10)0.48 (0.22-1.1)Clinically assessed high CVP from the JVP for detecting a high CVP3.1 (1.6-6.0)0.50 (0.37-0.68)Clinically assessed low CVP from the JVP for detecting a low CVP3.4 (1-9.9)0.65 (0.28-1.2)Chapter 12: Cholecystitis5% of ...