The roles of magnetic resonance and endoscopic retrograde cholangiopancreatography (MRCP and ERCP) in the diagnosis of patients with suspected sclerosing cholangitis: a cost-effectiveness analysis.
OBJECTIVE
The optimal approach for diagnosing sclerosing cholangitis remains unclear in the face of competing imaging technologies. We aimed to determine the most cost-effective strategy.


METHODS
A decision model compared three approaches in the work-up of patients with suspected sclerosing cholangitis; all included an initial test, with, if unsuccessful, performance of a second cholangiographic method. They were magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP), termed "MRCP_ERCP", ERCP and MRCP ("ERCP_MRCP"), or ERCP and a repeat ERCP ("ERCP_ERCP"). The implications of true and false positive and negative results with regard to costs and procedural complications were considered, including that of a liver biopsy, if indicated as a result of a negative work-up in the face of persistent clinical suspicion. The unit of effectiveness adopted was that of a correct diagnosis. Probability assumptions were derived from published literature, while cost estimates were derived from time-motion microanalyses or a national database, and expressed in Canadian dollars at 2004 values. Sensitivity analyses, including clinically relevant threshold analyses, were carried out.


RESULTS
The average cost-effectiveness ratios were $414 for MRCP_ERCP, $1101 for ERCP_MRCP and $1123 for ERCP_ERCP, per correct diagnosis. The ERCP_MRCP strategy was dominated (more expensive and less effective) by MRCP_ERCP, while ERCP_ERCP was more effective and more costly than MRCP_ERCP, at $289,292 per additional correct diagnosis. Sensitivity and threshold analyses confirmed the robustness of these findings.


CONCLUSIONS
Based on the model assumptions, a strategy of initial MRCP, followed, if negative, by ERCP is currently the most cost-effective approach to the work-up of patients with suspected sclerosing cholangitis.
Meagher
S
S
Division of Gastroenterology, McGill University Health Centre, Montreal General Hospital Site, McGill University, Montreal, Québec, Canada.
Yusoff
I
I
Kennedy
W
W
Martel
M
M
Adam
V
V
Barkun
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000191:economics / Q000379:methods*; D049448:Cholangiopancreatography, Magnetic Resonance / Q000191:economics / Q000379:methods*; D015209:Cholangitis, Sclerosing / Q000175:diagnosis*; D003362:Cost-Benefit Analysis; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011336:Probability; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity