Letter: The "inert" placebo.
D000367:Age Factors; D001249:Asthma / Q000139:chemically induced / Q000209:etiology*; D002648:Child; D004781:Environmental Exposure; D006801:Humans; D010919:Placebos; D012964:Sodium / Q000009:adverse effects; D013431:Sulfates / Q000009:adverse effects*; D013997:Time Factors; D014589:Utah
D010919:Placebos; D013431:Sulfates; D012964:Sodium