The Circles instrument obtained a measurement of the subject's motor control. Subjects were given a drawing of a circle and then asked to draw a circle, themselves, staying between lines on a sheet of paper given to them. Three different trials were administered. The initial trial served as a baseline. For the second trial, the subject was asked to draw the circle as quickly as possible, and for the third trial the subject was asked to draw the circle as slowly as possible.

WAVE 3: The Circles instrument (PDF 1.6MB) was administered to subjects in Cohorts 0 and 3.


Kochanska, Grazyna; Murray, Kathleen T.; Harlan, Elena T. Effortful control in early childhood: Continuity and change, antecedents, and implications for social development. Developmental Psychology. 2000 Mar. 36 (2): 220-232.

Related Internet Resources

Abstract of Kochanska, et. al. cited article from Education Resources Information Center

PHDCN Administration

Shaded boxes indicate that the measure is not available for a given wave/cohort.

Wave Cohort
0 3 6 9 12 15 18

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