Tracking: Concepts, methods and tools
Tracking can be defined as the tendency of an individual, or a collection of individuals, to maintain a particular course of growth over time relative to other individuals. A measure of tracking based on Cohen's kappa statistic and the tracking indices proposed by Foulkes-Davis and McMahan are considered. Applications, including significance testing, are made to a study of the growth of Guatemalan school children whose stature was measured longitudinally malan school children whose stature was measured longitudinally from 7 to 12 years of age. User-friendly programs for computing these indices are described and made available to interested readers.
Key wordsLongitudinal studies growth stability PC programs
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