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This study evaluated two pen testing strategies to predict the percentage of cattle in a pen shedding detectable E. coli O157:H7. Culture of a composite fecal sample most accurately detected pens with 37% or more cattle shedding E. coli O157:H7 in feces. A new pen test device most accurately detected pens with 16% or more individuals shedding. The likelihood of detecting E. coli O157:H7 with either method increased as pen prevalence increased. If both pen-level test methods were used together, pens could be classified as high, medium or low prevalence with less labor and expense than testing individual cattle.