Burns' (1984) attempt to explain the below average mean IQ scores reported for samples of learning disabled (LD) students through the use of the bivariate normal probability distribution was examined. Burns applied the bivariate distribution to a method of quantifying a learning disability based on a fixed achievement cut-off value. This explanation seems to have limited utility when applied to the preferred discrepancy based model of defining severe educational underachievement. Alternative explanations for the below average IQ of LD samples which focus on issues related to the referral, identification, and placement of children are presented.
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