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Table 2 Calculation of the score of a hypothetical test-taker

From: Challenging script concordance test reference standard by evidence: do judgments by emergency medicine consultants agree with likelihood ratios?

Disease/finding   Score of the categories
Categorized LR Very low (?2) Low (?1) Middle (0) High (+1) Very high (+2)
1. Meningitis       
??1A. Presence of headache Middle (0) 0 0 0.57 1 0.57
??1B. Absence of nausea/vomiting Middle (0) 0 0.07 1 0.07 0
??1C. Presence of neck stiffness Middle (0) 0 0.09 0.09 0.09 1
??1D. Presence of Brudzinski's sign Middle (0) 0 0 0.22 0.44 1
??1E. Presence of Kernig's sign Middle (0) 0 0 0.12 0.75 1
2. Myocardial infarction       
??2A. Presence of chest pain with radiation to both arms Very high (+2) 0 0 0.37 1 0.50
??2B. Absence of nausea/vomiting Middle (0) 0 0 1 0.07 0
??2C. Presence of sharp chest pain or stabbing Low (?1) 0.25 1 1 0.50 0.25
??2D. Presence of any ST segment elevation High (+1) 0.10 0 0.10 0.30 1
??2E. Presence of any Q wave High (+1) 0 0 1 1 1
3. Pneumonia (in a child)       
??3A. Presence of retraction Middle (0) 0 0 0.28 0.85 1
??3B. Absence of tachypnea Middle (0) 1 0.60 0.80 0.60 1
??3C. Presence of crackles High (+1) 0 0.16 0.33 1 1
??3D. Presence of grunting High (+1) 0 0 0.71 1 0.42
??3E. Absence of fever Middle (0) 0 0.71 1 0.28 0.14
4. Thoracic aortic dissection       
??4A. Presence of history of hypertension High (+1) 0 0.12 0.25 1 0.50
??4B. Presence of focal neurologic deficit Very high (+2) 0 0 0.25 1 0.62
??4C. Absence of pulse deficit Middle (0) 0.11 0.11 1 0.11 0.33
??4D. Absence of enlarged aorta/wide mediastinum in CXR Low (?1) 0 1 0.40 0.80 0.80
??4E. Absence of sudden chest pain Low (?1) 0.66 0.33 1 0.50 0
5. Appendicitis       
??5A. Absence of anorexia Middle (0) 0.25 0.50 1 0.12 0
??5B. Presence of guarding High (+1) 0 0.12 0.37 1 0.37
??5C. Absence of rebound tenderness Very low (?2) 0.16 1 0.66 0.33 0.33
??5D. Presence of psoas sign High (+1) 0 0 0.83 1 0.66
??5E. WBC?=?12,000 Middle (0) 0 0.12 0.25 1 0.50
6. Congestive heart failure       
??6A. Presence of third heart sound Very high (+2) 0 0.11 0 0.55 1
??6B. Absence of cardiomegaly in CXR Low (?1) 0.42 1 0.42 0.14 0.14
??6C. Presence of interstitial edema in CXR Very high (+2) 0 0 0.12 0.75 1
??6D. Presence of atrial fibrillation in EKG High (+1) 0 0.16 1 0.83 0.50
??6E. Presence of lateral EKG changes High (+1) 0 0 1 0.66 0
SUM 21.73 (out of 30)
  1. If a test-taker answered our script concordance test based on evidence-based likelihood ratios (LRs), and his/her answers were scored based on the judgments of this study's reference panel, the test-taker would get a score of 21.73 out of 30. For the above calculations, the numbers representing the judgments were categorized as very low, low, middle, high, and very high, similar to five-point Likert scales, using cutoff points of ?6, ?2, 2, and 6. Subsequently, the score of each category was calculated based on the judgments. Then, for LR of each finding, we identified its category (`categorized LR column) and its corresponding score (italicized number). Finally, we added up all italicized numbers. The calculation of the scores based on the judgments of the reference panel is explained elsewhere [16].