Cost-Effectiveness Analysis of Subtraction Scintigraphy in Patients with Acute Lower Gastrointestinal Tract Hemorrhage

Article Figures & Data

Download figure
Open in new tab
Download powerpoint
FIGURE 1.
Composite diagnostic algorithm for patients with LGIH. A% and B% represent alternative diagnostic strategies. +ve = positive; −ve = negative.
Download figure
Open in new tab
Download powerpoint
FIGURE 2.
Decision-tree analysis for CS alone, with totals of 34 deaths and 83 complications and total cost of $943,128. FN = false-negative results; FP = false-positive results; TN = true-negative results; TP = true-positive results; +ve = positive; −ve = negative.
Download figure
Open in new tab
Download powerpoint
FIGURE 3.
Decision-tree analysis for CS, RSS, and ASSS combined, with totals of 28 deaths and 70 complications and total cost of $869,284. FN = false-negative results; FP = false-positive results; TN = true-negative results; TP = true-positive results; +ve = positive; −ve = negative.
Download figure
Open in new tab
Download powerpoint
FIGURE 4.
Decision-tree analysis for CS and ASSS combined, with totals of 26 deaths and 64 complications and total cost of $787,344. FN = false-negative results; FP = false-positive results; TN = true-negative results; TP = true-positive results; +ve = positive; −ve = negative.
Download figure
Open in new tab
Download powerpoint
FIGURE 5.
Composite diagnostic algorithm for patients with LGIH, with minor adjustments to proportions. A% and B% represent alternative diagnostic strategies. +ve = positive; −ve = negative.

TABLE 1

Summary of Data Used in Analysis

Variable	Value (reference)
Mean life expectancy	80.5 y (7)
Mortality rate for patients with acute LGIH^*	4% (3,8)
Scintigraphy-associated mortality	0% (9)
Scintigraphy-associated complication rate	0% (9)
Scintigraphy-associated cost	$492 (6)
Angiography-associated mortality	0% (3,9,10)
Angiography-associated complication rate^*	2% (3,9,10)
Angiography-associated cost	$1,376 (6)
Embolization-associated complication rate^*	0% (11)
Embolization-associated cost	$144 (6)
Surgery-associated mortality, with localization of bleeding	13% (12,13)
Surgery-associated mortality, without localization of bleeding	30% (12,13)
Surgery-associated complication rate, with localization of bleeding	15% (14)
Surgery-associated complication rate, without localization of bleeding	83% (14)
Surgery-associated cost	$1,124 (6)
Surgery as a result of positive scintigraphy	15% (20)
Angiography as a result of positive scintigraphy	85% (20)
Positive angiography and positive scintigraphy	39% (20)
Negative angiography and positive scintigraphy	61% (20)
Positive angiograms only suggestive of bleeding	42% (20)
Rate of rebleeding in acute LGIH	15% (15,16)
Positive angiography leading to surgery	25% (20)
Positive angiography leading to embolization	50% (20)
Blind surgery	12% (17)

TABLE 2

Summary of Clinical Results Used in Analysis

Variable	Value
Mean age of patient cohort	68.9 y
Rate of false-positive findings for CS alone	10.3%
Rate of false-negative findings for CS alone	1.1%
Rate of true-positive findings for CS alone	14.8%
Rate of true-negative findings for CS alone	73.8%
Rate of false-positive findings for CS and subtraction	4.0%
Rate of false-negative findings for CS and subtraction	1.7%
Rate of true-positive findings for CS and subtraction	14.4%
Rate of true-negative findings for CS and subtraction	79.9%
Negative scintigraphy; rescanned because of rebleeding^*	8%

TABLE 4

Results of Sensitivity Analysis of Decision-Tree Data Obtained with Various Subtraction Techniques

		Reduction compared with CS alone
Strategy	Parameter	This study	Worst-case scenario	Best-case scenario
CS, RSS, and ASSS	Cost per patient	$74	$32	$74
	Complications	13	3	20
	Deaths	6	2	8
CS and ASSS	Cost per patient	$65	$65	$156
	Complications	19	7	28
	Deaths	8	3	14