Table 1.

Types of oral food challenges, definitions, and comments

Type of Oral Food Challenge	Definition	Comment
Open	The patient and the physician know the food that is given	Easy to prepare and administer
Single-blinded	The physician but not the patient knows the food given	Suitable for older children and young adults who have heightened anxiety
Double-blind challenge or double-blind placebo controlled	Neither the physician (or any observer) nor the patient knows what food is given	Relies on objective symptoms
Graded	Food is given in incremental amounts	Most commonly used
Single feeding	The whole serving is given	Used when food allergy reaction is not expected
Plain	The food is given in its plain form	Example: a challenge with a cup of cow's milk
Baked	The food is baked in with other ingredients	Example: challenge with a cookie or a cake baked with cow's milk
Single	One food is given	Example: peanut
Multiple	Multiple foods are challenged simultaneously	Example: challenge done with a number of tree nuts mixed together
Threshold determining	Challenge is stopped at a preset amount and not carried out to a full serving amount	Used for research