OBJECTIVE: To identify the most useful combinations of symptoms and the results 
of radioallergosorbent tests (RASTs) and skin prick tests (SPTs) for the 
diagnosis of allergic rhinitis.
DESIGN: A prospective comparison was made of symptoms and the results of RASTs 
and SPTs with 7 different nasal allergies; the references used were the 
"consensus diagnoses" provided by 3 experts.
SETTING: Nineteen general practices in The Netherlands.
PATIENTS: 365 consecutive patients aged 12 or over who visited their general 
practitioner because of chronic or recurrent nasal symptoms between 1 March 1990 
and 1 March 1991.
MAIN OUTCOME MEASURES: The most useful combinations of items from the history, 
RASTs, and SPTs, for the diagnosis of 7 different nasal allergies; the 
predictive probabilities of these combinations.
RESULTS: Diagnostic criteria could be drawn up resulting in a near-perfect 
discrimination between patients diagnosed as having allergic rhinitis and 
patients diagnosed as not having allergic rhinitis. Most of these criteria 
combined only a single item from the history with either RAST or SPT. For nearly 
all nasal allergies, both the negative predictive probabilities and the positive 
predictive probabilities were 97% or more.
CONCLUSIONS: The common nasal allergies can be diagnosed with a very high 
certainty with the aid of simple diagnostic criteria. Data from a strictly 
limited case history combined with either RAST or SPT are sufficient.