Tools

Add a finding for this diagnosis

Add prevalence for this diagnosis

Switch to display mode

Switch to sensitivity and specificity

Sort findings by Tag

Sort findings by Differential Diagnosis

Jump To

Good Positive and Negative Likelihood Ratios

Good Negative Likelihood Ratio

Good Positive Likelihood Ratio

Acute GI Bleeding: Likelihood Ratios

Introduction: Acute gastrointestinal bleeding, lumping lower and upper together here. See also Upper GI Bleed.

[Edit Diagnosis] [Merge dx] [Add prevalence]

Tags: Gastrointestinal Problem Tag this Diagnosis.

The likelihood ratios of findings for Acute GI Bleeding are listed below. See the left navigation bar to change the display.

Pre-Test Probability (Prevalence): %.	Post-Test Probability (Predictive Value): %.	Switch to display mode.
Note that calculating probabilities from more than one** finding is inherently inaccurate because findings are not independent. (For example, using two positive findings that share a common pathogenesis is likely to overestimate the true probability.)

Good Positive and Negative Likelihood Ratios
Finding	Result	+LR	-LR
[ + ] Tagged RBC Scan	+ 0 -	18.6	0.1
In animal models, sensitivity down to .04 - .1 ml/min flow. However, data suggests at least 22% mislocalization rate. Study: Radiographics. 2007 Jul-Aug;27(4):1055-70. PMID: 17620467 World J Gastroenterol. 2010 Aug 21;16(31):3957-63. PMID: 20712058
[ + ] CT angiography	+ 0 -	5.9	0.1
In animal models, sensitivity down to .3 ml/min Study: World J Gastroenterol. 2010 Aug 21;16(31):3957-63. PMID: 20712058
[ + ] Angiography	+ 0 -	inf	0.4
for upper GI bleeding. sensitivity 63-90% Study: Radiographics. 2007 Jul-Aug;27(4):1055-70. PMID: 17620467

Good Negative Likelihood Ratio
Finding	Result	+LR	-LR
[ + ] Upper Endoscopy	+ 0 -	1.3	0.3
sensitivity 92-98%, specificity 30-100% Study: Radiographics. 2007 Jul-Aug;27(4):1055-70. PMID: 17620467

Good Positive Likelihood Ratio
Finding	Result	+LR	-LR
[ + ] Angiography	+ 0 -	inf	0.6
for lower GI bleeding. sensitivity 40-86% Study: Radiographics. 2007 Jul-Aug;27(4):1055-70. PMID: 17620467