Robust trend analysis in predicting histamine provocation concentration

Trend analysis is used to predict the histamine provocation concentration PC20 during the so-called challenge test, where increasing doses of the bronchoconstricting agent are given to a patient and the spirometric examination is subsequently performed. Classical least-squares analysis of trends as well as least absolute deviations analysis are compared. The results are interesting and promising from a statistical as well as medical point of view. The methods presented can be applied to many practical problems in medicine.