Investigations

• white cell scanning ^c

Why?

A normal white cell scan makes inflammatory bowel disease less likely

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability	LR- (95% CI)	Post-test Probability
children with suspected inflammatory bowel disease c (pre-test probability: 50%)	inflammatory bowel disease (histology)	white cell scanning: positive if activity seen in the gut in early stages	2.8 (1.1 to 7.1)	74%	0.10 (0.024 to 0.41)	9%