Tracking: Concepts, methods and tools
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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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- Berensen G.S., Foster T.A., Frank G.C., Frerichs R.R., Srinivasan S.R., Voors A.W. and Webber L.S., 1978. Cardiovascular disease risk factor variables at the preschool age: The Bogalusa Heart Study. Circulation, 57: 603–612.Google Scholar
- Carter R.L. and Yang M.C.K., 1986. Large-sample inference in random coefficient regression models. Communications in Statistics — Theory and Methods, 8: 2507–2526.Google Scholar
- Clarke W.R., Schrot H.F., Leaverton P.E., Connor W.E. and Lauer R.M., 1978. Tracking of blood lipids and blood pressures in school age children: The Muscatine Study. Circulation, 58: 626–634.Google Scholar
- Cohen J (1960) A coefficient of agreement for nominal scales. Educational and Psychological Measurement, 20: 37–46.Google Scholar
- Fleiss J.L., 1981. Statistical Methods for Rates and Proportions, Second Edition, NY: Wiley.Google Scholar
- Levine R.S., Hennekens C.H., Klein B., Gourley J., Briese F.W., Hokanson J., Gelband H. and Jesse J.M., 1978. Tracking correlations of blood pressure levels in infancy. Pediatrics, 61: 121–125.Google Scholar
- Rosner B., Hennekins C.H., Kass E.H. and Miall W.E., 1977. Age-specific correlation analysis of longitudinal blood pressure data. Amer J Epid, 106: 306–313.Google Scholar
- Schneiderman E.D., Willis S.M. Kowalski C.J. and Ten Have T.R., 1990c. A GAUSS program for computing the Foulkes-Davis tracking index for polynomial growth curves. Amer J Hum Biol, submitted for publication.Google Scholar
- Sen P.K., 1960. On some convergence properties of U-statistics. Calcutta Stat Assn Bull, 10: 1–18.Google Scholar
- Voors A.W., Webber L.S. and Berenson G.S., 1979. Time course studies of blood pressure in children — The Bogalusa Heart Study. Amer J Epid, 109: 320–334.Google Scholar