Measurement theories have gone through a lot of evolution; one of which is Item Response Theory, which is an improvement on the Classical Test Theory (CTT). This study looked into the difficulty status or difficulty parameter of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-IV). 512 subjects were randomly selected and administered the WPPSI-IV instrument. Findings from the study show that 241 items were good, 6 were easy, and 23 were difficult. It was therefore concluded that some items in the WPPSI-IV are adaptable and adoptable for use to measure children’s intelligence, age 7. It was recommended that WPPSI-IV is good enough and should therefore be administered to measure children’s intelligence approximately age 7. Also, it was recommended that the difficult and easy items could be replaced with better ones.
Keywords: Classical Test Theory, Intelligence, Item Response Theory, Measurement, Pupils.
