Chapter 4 The D-score

Section 2 provided historical background on the nature of child development. Section 3 discussed three general quantification approaches. This section explains how to apply the unit-based approach to arrive at the D-score scale. The text illustrates the process with real data.

  • Dutch Development Instrument (DDI) (4.1)
  • Milestone passing by age and by D-score (4.2, 4.3)
  • How do age and D-score relate? (4.4)
  • Role of the measurement model (4.5)
  • Item and person response functions (4.6)
  • Engelhard invariance criteria (4.7)
  • Why the Rasch model? (4.8)