Thousands of allergists and millions of patients have long "known" that hay-fever shots are beneficial. More cautious scientists have waited for reliable proof which is hard to come by because 1) like all allergies, ragweed pollinosis is mixed up with emotional problems, and many patients think they feel better if they get any sort of treatment at all; and 2) symptoms vary as unpredictably as shifts in the wind.
At Massachusetts General Hospital, Dr. Francis C. Lowell and Dr. William Franklin designed a rigorous test to get around both difficulties. They kept a daily record of their patients' symptoms for...