Ten subjects with exercise-induced asthma participated in an experiment to compare the protective effect of a drug administered in four dose levels. Saline was used as a control. The variable of interest was change in FEV1 after administration of the drug or saline. The results were as follows:

Dose Level of Drug (mg/ml)
Subject Saline 2 10 20 40 1 :68 :32 :14 :21 :32 2 1:55 :56 :31 :21 :16 3 1:41 :28 :11 :08 :83 4 :76 :56 :24 :41 :08 5 :48 :25 :17 :04 :18 6 3:12 1:99 1:22 :55 :75 7 1:16 :88 :87 :54 :84 8 1:15 :31 :18 :07 :09 9 :78 :24 :39 :11 :51 10 2:12 :35 :28 þ:11 :41 Can one conclude on the basis of these data that different dose levels have different effects?
Let a ¼ :05 and find the p value.