Table 2.

Sensitivity, specificity, positive predictive values (PPVs), and negative predictive values (NPVs) of SPT and serum IgE for the diagnosis of food allergy to wheat

Cutoff levels	Population used in the study	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)
Wheat serum IgE level >0.36 kU/L124	Forty children with diagnosis confirmed with OFC or DBPCFC to wheat	95	67	72	93
Wheat serum IgE =10.1 kU/L125	One hundred seventy three children with confirmed diagnosis of IgE mediated food allergy to wheat, either by OFC or by recent history of anaphylaxis	61	74	75	60
Wheat serum IgE =26 kU/L (90% decision point)126	Twenty three children with DBPCFC confirmed diagnosis of IgE mediated food allergy to wheat	61	92	74	87
Wheat serum IgE =100 kU/L (95% decision point)126	Twenty three children with DBPCFC confirmed diagnosis of IgE mediated food allergy to wheat	13	100	100	76
Wheat SPT (wheat diameter =3 mm)124	Forty children with diagnosis confirmed with OFC or DBPCFC to wheat	89	71	74	88
ώ-5 gliadin serum IgE =0.41 kU/L IgE mediated food allergy125	One hundred seventy three children with confirmed diagnosis of IgE mediated food allergy to wheat, either by OFC or by recent history of anaphylaxis	72	79	81	69
ώ-5 gliadin serum IgE =0.89 kU/L for WDEIA127	Fifty children and adults with confirmed diagnosis of IgE mediated food allergy to wheat, either by OFC or by recent history of anaphylaxis	78	96	N/A	N/A

Abbreviations: IgE, immunolglobulin E; DBPCFC, double blind placebo controlled food challenge; OFC, oral food challenge; SPT, skin prick test; WDEIA, wheat-dependent, exercise-induced anaphylaxis; N/A, not available.