Carbon dioxide insufflation for endoscopic retrograde cholangiopancreatography: A meta-analysis and systematic review

Table 1 Search strategies

Databases	Period of search	Search strategies
The Cochrane library	Until 1st December 2011	1. MeSH descriptor Cholangiopancreatography, Endoscopic Retrograde explode all trees
		2. (endoscopic retrograde cholangiopancreatograph*): ti, ab, kw OR (ERCP): ti, ab, kw
		3. MeSH descriptor Carbon Dioxide explode all trees
		4. (carbon dioxide): ti, ab, kw OR (CO2): ti, ab, kw
		5. 1 OR 2
		6. 3 OR 4
		7. 5 AND 6
MEDLINE via PubMed	Until 1st December 2011	1. “Cholangiopancreatography, Endoscopic Retrograde” [MeSH] OR endoscopic retrograde cholangiopancreatograph* [tiab] OR ERCP [tiab]
		2. “Carbon Dioxide” [Mesh] OR carbon dioxide [tiab] OR CO2 [tiab]
		3. 1 AND 2
EMBASE via embase.com	Until 1st December 2011	1. ‘endoscopic retrograde cholangiopancreatography’/exp OR ‘endoscopic retrograde cholangiopancreatography’
		2. ‘ercp’/exp OR ercp
		3. ‘carbon dioxide’/exp OR ‘carbon dioxide’
		4. ‘CO2’/exp OR CO2
		5. 1 OR 2
		6. 3 OR 4
		7. 5 AND 6
Science citation index expanded	Until 1st December 2011	1. TS = (‘endoscopic retrograde cholangiopancreatograph*’ OR ERCP)
		2. TS = (‘carbon dioxide’ OR CO2)
		3. 1 AND 2
CBM	Until 1st December 2011	Search strategy in Chinese. Includes search terms similar to the terms used in MEDLINE

MEDLINE: Medical Literature Analysis and Retrieval System Online; EMBASE: Excerpta Medica Database; CBM: Chinese Biomedical Literature Database; MeSH: Medical Subject Heading; ERCP: Endoscopic retrograde cholangiopancreatography.