<P> The Denver Developmental Screening Test (DDST), commonly known as the Denver Scale, is a test for screening cognitive and behavioral problems in preschool children . </P> <P> The scale reflects what percentage of a certain age group is able to perform a certain task . In a test to be administered by a pediatrician or other health or social service professional, a subject's performance against the regular age distribution is noted . Tasks are grouped into four categories (social contact, fine motor skill, language, and gross motor skill) and include items such as smiles spontaneously (performed by 90% of three - month - olds), knocks two building blocks against each other (90% of 13 - month - olds), speaks three words other than "mom" and "dad" (90% of 21 - month - olds), or hops on one leg (90% of 5 - year - olds). </P>

What is the purpose of denver developmental screening test
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