<qa>  What is the new protocol for cold dry air provocation that has been validated as aCold, dry air exposure has been shown to be a reliable method for diagnosis of nasal hyperreactivity. The new, shorter protocol for cold dry air provocation that recently has been validated as a useful diagnostic tool to evaluate nasal hyperreactivity with high specificity and sensitivity, is already a major step forward but still rather time-consuming and not always very practical in use. 