This study compared level of agreement among four models used to diagnose learning disabilities (LD), including the simple discrepancy, intraindividual, intellectual ability-achievement, and underachievement models. The simple discrepancy model diagnosed significantly more college students with LD than the others. The highest agreement was between intraindividual and intellectual ability-achievement models, the lowest between simple discrepancy and underachievement models. (Contains references.) (Author/DB)