Defining learning disability

Diagnoses of learning disability have real-life impact, in terms of service delivery. Currently, whether or not a person meets the diagnostic criteria depends on having an impairment of intellectual functioning, typically measured as an IQ below 70, along with a significant impairment of adaptive or social functioning. If over this IQ threshold, an individual may not get access to the resources they need even if it is abundantly clear that cannot cope without help. How reliable and valid is the current cut-off point? Do we need to move to a definition of learning disability based on clinical judgement rather than IQ score?