Table 3.

Advantages and disadvantages of ISAC, immunoCAP, and skin prick tests

	Advantages	Disadvantages
ISAC	• 30 μl of serum or plasma (capillary or venous blood)	• Manual method
	• 112 allergens can be assayed in parallel	• Semi-quantitative assay
	• Natural and recombinants proteins	• Less sensitive
	• Less allergen needed (approximately 100, 000-fold, pg vs. μg) per assay	• More variability in the inter-assay analysis for certain allergens
	• No interference from very high total IgE	• Greater coefficient of variation
		• Some allergen sources are not included
		• Less appropriate for monitoring sensitization
		• Potential interference between IgE and other isotypes, principally IgG
ImmunoCAP	• Automatic method	• 40 μl of serum per allergen
	• Quantitative assay	• One allergen per assay
	• High sensitivity	• Detect low-affinity antibody that may have little to no clinical relevance
	• Lower coefficient of variation
	• Natural or recombinants proteins or crude extracts
	• Appropriate for monitoring sensitization
Skin prick test	• High sensitivity (extract-dependent)	• Manual
	• Immediate reading	• One allergen per prick
		• Only crude extracts
		• Not appropriate for monitoring sensitization