CDC Growth Charts for the United States

Series 11, Number 246

May 2002

Table 24 percentile column headings aligned correctly 6/30/2010

2000 CDC Growth Charts for the United States: Methods and Development

Copyright information All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated. Suggested Citation Kuczmarski RJ, Ogden CL, Guo SS, et al. 2000 CDC growth charts for the United States: Methods and development. National Center for Health Statistics. Vital Health Stat 11(246). 2002 Library of Congress Cataloging-in-Publication Data 2000 CDC growth charts for the United States: methods and development. p. cm. — (DHHS publication ; no. (PHS) 2002-1696) (Vital and health statistics. Series 11, Data from the National Health Survey ; no. 246) ‘‘May, 2002.’’ ISBN 0-8406-0575-7 1. Children—Anthropometry—United States—Statistics. 2. Children— United States—Growth—Statistics. 3. United States—Statistics, Vital. I. Series. II. Series: Vital and health statistics. Series 11, Data from the National Health Survey ; no. 246 GN63 .A225 2001 305.23'0973'021—dc21 2001051405 For sale by the U.S. Government Printing Office Superintendent of Documents Mail Stop: SSOP Washington, DC 20402-9328 Printed on acid-free paper.

Series 11, Number 246

2000 CDC Growth Charts for the United States: Methods and Development

Data From the National Health Examination Surveys and the National Health and Nutrition Examination Surveys

DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention National Center for Health Statistics Hyattsville, Maryland May 2002 DHHS Publication No. (PHS) 2002-1696

National Center for Health Statistics Edward J. Sondik, Ph.D., Director Jack R. Anderson, Deputy Director Jack R. Anderson, Acting Associate Director for International Statistics Jennifer H. Madans, Ph.D., Associate Director for Science Lawrence H. Cox, Ph.D., Associate Director for Research and Methodology Jennifer H. Madans, Ph.D., Acting Associate Director for Analysis, Epidemiology, and Health Promotion Edward L. Hunter, Associate Director for Planning, Budget, and Legislation Jennifer H. Madans, Ph.D., Acting Associate Director for Vital and Health Statistics Systems Douglas L. Zinn, Acting Associate Director for Management Charles J. Rothwell, Associate Director for Information Technology and Services Division of Health Examination Statistics Clifford L. Johnson, M.S.P.H., Director Rosemarie Hirsch, M.D., M.P.H., Chief Analysis Branch Carolyn Petty-Martin, Acting Chief Operations Branch Vicki L. Burt, Sc.M., R.N., Chief Planning Branch Lewis Berman, M.S., Chief Information Management Branch

Acknowledgments

W

e wish to gratefully acknowledge the contributions of many individuals who had various roles in the growth chart revision process. These contributions include statistical and computer programming expertise, data and summary statistics, graphical support, and knowledge and experience in the areas of pediatric growth and growth charts. We also wish to thank Thelma Sanders and Zung Le for their editorial support. In addition to acknowledging the contributions of all individuals identified in appendix I of this report, the following persons are also recognized, with their affiliations at the time of their contribution: Phil Batty Center for Health Information Management and Epidemiology State of Missouri Department of Health Jefferson City, MO Fred Buhr Center for Health Statistics State of Wisconsin Department of Health and Family Services Madison, WI Margaret Carroll National Center for Health Statistics Centers for Disease Control and Prevention Hyattsville, MD

John Chang Computer Information Systems and Support Services Nova Research Company Bethesda, MD Chris Cronk Center for Health Statistics State of Wisconsin Department of Health and Family Services Madison, WI William Davis Klemm Analysis Group, Inc. Washington, DC Catherine Duran National Center for Health Statistics Centers for Disease Control and Prevention Hyattsville, MD Odell Eldridge Computer Information Systems and Support Services Nova Research Company Bethesda, MD Stephen Sloan National Center for Health Statistics Centers for Disease Control and Prevention Hyattsville, MD Christine Zeller Department of Community Health Wright State University Yellow Springs, OH

iii

Contents

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

iii

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Historical Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Concerns Surrounding the 1977 Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 1 2 3

Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Data Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Data Exclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Statistical Curve Smoothing Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 3 5 5

Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Observed and Smoothed Percentiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Evaluation of the Revised Growth Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Differences Between the 1977 NCHS and the 2000 CDC Growth Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10 10 10 11

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Revision Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Growth Chart Workshops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Major Features of the 2000 CDC Growth Charts for the United States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the Revised Growth Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Specialized Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Growth Chart Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 11 12 12 12 13 14

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

15

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16

Appendix I. Description of Growth Chart Workshops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Workshop 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Workshop 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Workshop 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Workshop 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

187 187 188 189 189

Appendix Table I.

Participants in the NCHS growth chart workshops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

187

Figures 1. 2. 3. 4.

Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Boys length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Girls length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

19 20 21 22 v

5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37.

vi

Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Boys weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Girls weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Boys head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, birth to 36 months: Girls head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, 2 to 20 years: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, 2 to 20 years: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, 2 to 20 years: Boys stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles, 2 to 20 years: Girls stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th, 97th percentiles, 2 to 20 years: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th, 97th percentiles, 2 to 20 years: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th, 97th percentiles: Boys weight-for-stature . . . Individual growth chart 3rd, 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th, 97th percentiles: Girls weight-for-stature . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, birth to 36 months: Boys length-for-age and weight-for-age percentiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, birth to 36 months: Girls length-for-age and weight-for-age percentiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, birth to 36 months: Boys head circumference-for-age and weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, birth to 36 months: Girls head circumference-for-age and weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, 2 to 20 years: Boys stature-for-age and weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 90th, 95th percentiles, 2 to 20 years: Girls stature-for-age and weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th percentiles, 2 to 20 years: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th percentiles, 2 to 20 years: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th percentiles: Boys weight-for-stature . . . . . . . . . . . . . Clinical growth chart 5th, 10th, 25th, 50th, 75th, 85th, 90th, 95th percentiles: Girls weight-for-stature . . . . . . . . . . . . . Smoothed percentile curves, 22–39 months: Boys length-for-age and stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . Smoothed percentile curves, 22–39 months: Girls length-for-age and stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . Smoothed percentile curves, 75–106 cm: Boys weight-for-length and weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . Smoothed percentile curves, 75–106 cm: Girls weight-for-length and weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Boys recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Boys recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Girls recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66.

Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Girls recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 46–102 cm: Boys weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 46–102 cm: Boys weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 46–102 cm: Girls weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 46–102 cm: Girls weight-for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Boys head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Boys head circumference-for-age. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, birth to 36 months: Girls head circumference-for-age. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, birth to 36 months: Girls head circumference-for-age. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 78–120 cm: Boys weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 78–120 cm: Boys weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 78–120 cm: Girls weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 78–120 cm: Girls weight-for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 24–237 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 24–237 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Boys stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 24–237 months: Boys stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Girls stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 95th percentile curves to empirical data points, 24–237 months: Girls stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 85th, 95th percentile curves to empirical data points, 24–237 months: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 3rd, 10th, 50th, 90th, 97th percentile curves to empirical data points, 24–237 months: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of smoothed 5th, 25th, 50th, 75th, 85th, 95th percentile curves to empirical data points, 24–237 months: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 vii

67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95.

viii

Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Boys length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Boys length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Girls length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Girls length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 46–103 cm: Boys weight­ for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 46–103 cm: Boys weight­ for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 46–103 cm: Girls weight­ for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 46–103 cm: Girls weight­ for-length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Boys head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Boys head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, birth to 33 months: Girls head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, birth to 33 months: Girls head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 84–122 cm: Boys weight­ for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 84–122 cm: Boys weight­ for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 84–122 cm: Girls weight­ for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 84–122 cm: Girls weight­ for-stature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 27–237 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 27–237 months: Girls weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Boys stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 27–237 months: Boys stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Girls stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 95th percentile curves, 27–237 months: Girls stature-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 85th, 95th percentile curves, 27–237 months: Boys body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 3rd, 10th, 50th, 90th, 97th percentile curves, 27–237 months: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Percent of empirical data below smoothed 5th, 25th, 50th, 75th, 85th, 95th percentile curves, 27–237 months: Girls body mass index-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Boys weight-for-age . . . . . . . .

85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113

96. 97.

98.

99. 100. 101.

102.

103. 104. 105.

106. 107. 108.

Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Girls weight-for-age . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Boys recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Girls recumbent length-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 49–94 cm: Boys weight-for-length. . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 49–94 cm: Girls weight-for-length. . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Boys head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, birth to 36 months: Girls head circumference-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 91–120 cm: Boys weight-for-stature . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 91–120 cm: Girls weight-for-stature . . . . . . . . . . . . Comparison of revised CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 24–213 months: Boys weight-for-age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 24–213 months: Girls weight-for-age . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 24–213 months: Boys stature-for-age . . . . . . . . . . . Comparison of CDC 2000 smoothed 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th percentiles with NCHS 1977 smoothed 5th, 10th, 25th, 50th, 75th, 90th, 95th percentile curves, 24–213 months: Girls stature-for-age . . . . . . . . . . .

114

115

116 117 118

119

120 121 122

123 124 125 126

Text Tables A. B. C. D.

Charts included in the 1977 NCHS Growth Charts and the 2000 CDC Growth Charts . . . . . . . . . . . . . . . . . . . . . . . . . . Source of data for each growth chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Primary and supplemental data sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Summary of curve smoothing procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 3 4 6

Detailed Tables 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

Unweighted sample sizes for weight-for-age chart by sex, age, and data source: Births to 36 months . . . . . . . . . . . . . . Unweighted sample sizes for recumbent length-for-age chart by sex, age, and data source: Birth to 36 months . . . . . . Unweighted sample sizes for weight-for-recumbent length chart by sex, length interval, and data source: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Unweighted sample sizes for head circumference-for-age chart by sex, age, and data source: Birth to 36 months . . . . Unweighted sample sizes for weight-for-stature chart by sex, stature interval, and data source: 77 to 121 cm . . . . . . . Unweighted sample sizes for weight-for-age chart by sex, age, and data source: 2 to 20 years . . . . . . . . . . . . . . . . . . . Unweighted sample sizes for stature-for-age chart by sex, age, and data source: 2 to 20 years . . . . . . . . . . . . . . . . . . . Unweighted sample sizes for body mass index (BMI)-for-age chart by sex, age, and data source: 2 to 20 years . . . . . Observed mean, standard deviation, and selected percentiles for weight (in kilograms) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Observed mean, standard deviation, and selected percentiles for recumbent length (in centimeters) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Observed mean, standard deviation, and selected percentiles for weight (in kilograms) by sex and recumbent length: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Observed mean, standard deviation, and selected percentiles for head circumference (in centimeters) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

127 128 129 130 131 132 134 136 138 139 140 141 ix

13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24.

x

Observed mean, standard deviation, and selected percentiles for weight (in kilograms) by sex and stature: 77 to 121 cm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Observed mean, standard deviation, and selected percentiles for weight (in kilograms) by sex and age: 2 to 20 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 Observed mean, standard deviation, and selected percentiles for stature (in centimeters) by sex and age: 2 to 20 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Observed mean, standard deviation, and selected percentiles for body mass index (kilograms/meter2) by sex and age: 2 to 20 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 L, M, and S parameters and selected smoothed percentiles for weight (in kilograms) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 L, M, and S parameters and selected smoothed percentiles for recumbent length (in centimeters) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 L, M, and S parameters and selected smoothed percentiles for weight (in kilograms) by sex and recumbent length (in centimeters): Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 L, M, and S parameters and selected smoothed percentiles for head circumference (in centimeters) by sex and age: Birth to 36 months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 L, M, and S parameters and selected smoothed percentiles for weight (in kilograms) by sex and stature (in centimeters): 77 to 121 cm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 L, M, and S parameters and selected smoothed percentiles for weight (in kilograms) by sex and age: 2 to 20 years . . 160 L, M, and S parameters and selected smoothed percentiles for stature (in centimeters) by sex and age: 2 to 20 years . 169 L, M, and S parameters and selected smoothed percentiles for body mass index (BMI, kilograms/meter2) by sex and age: 2 to 20 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178

Objectives This report provides detailed information on how the 2000 Centers for Disease Control and Prevention (CDC) growth charts for the United States were developed, expanding upon the report that accompanied the initial release of the charts in 2000.

Methods The growth charts were developed with data from five national health examination surveys and limited supplemental data. Smoothed percentile curves were developed in two stages. In the first stage, selected empirical percentiles were smoothed with a variety of parametric and nonparametric procedures. In the second stage, parameters were created to obtain the final curves, additional percentiles and z-scores. The revised charts were evaluated using statistical and graphical measures.

Results The 1977 National Center for Health Statistics (NCHS) growth charts were revised for infants (birth to 36 months) and older children (2 to 20 years). New body mass index-for-age (BMI-for-age) charts were created. Use of national data improved the transition from the infant charts to those for older children. The evaluation of the charts found no large or systematic differences between the smoothed percentiles and the empirical data.

Conclusion The 2000 CDC growth charts were developed with improved data and statistical procedures. Health care providers now have an instrument for growth screening that better represents the racial-ethnic diversity and combination of breast- and formulafeeding in the United States. It is recommended that these charts replace the 1977 NCHS charts when assessing the size and growth patterns of infants, children, and adolescents. Keywords: growth charts c height c length c weight c body mass index c head circumference c NHANES

2000 CDC Growth Charts for the United States: Methods and Development Robert J. Kuczmarski, M.S.P.H., M.P.H., R.D., Dr.P.H., Division of Digestive Diseases and Nutrition, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health; Cynthia L. Ogden, M.R.P., Ph.D., Division of Health Examination Statistics; Shumei S. Guo, M.S., Ph.D.,Center for Lifetime Health Research, School of Medicine, Wright State University; Laurence M. Grummer-Strawn, M.A., M.P.A., Ph.D., Division of Nutrition and Physical Activity, National Center for Chronic Disease Prevention and Health Promotion; Katherine M. Flegal, M.S., M.P.H., Ph.D., Division of Health Examination Statistics; Zuguo Mei, M.P.H., M.D., Division of Nutrition and Physical Activity, National Center for Chronic Disease Prevention and Health Promotion; Rong Wei, M.S., Ph.D., Office of Research and Methodology; Lester R. Curtin, Ph.D., Office of Research and Methodology; Alex F. Roche, M.D., Ph.D., D.Sc., F.R.A.C.P., Center for Lifetime Health Research, School of Medicine, Wright State University; Clifford L. Johnson, M.S.P.H., Division of Health Examination Statistics

Introduction

T

he National Center for Health Statistics (NCHS) growth charts that have been in use since 1977 have been revised. The revised version, known as the Centers for Disease Control and Prevention (CDC) Growth Charts: United States released in 2000, is recommended for use in clinical practice and research to assess size and growth in U.S. infants, children, and adolescents (1). The 2000 CDC Growth Charts consist of a set of charts for infants, birth to 36 months of age and a set of charts for children and adolescents from ages 2 to 20 years. The charts for infants include sex-specific smoothed percentile curves for weight-for-age, recumbent length-for-age, head circumference-for-age, and weight-for­ recumbent length; the charts for children and adolescents include weight-for-age,

stature-for-age, and body mass index (BMI)-for-age curves. The BMI-for-age charts represent a new tool that can be used by health care providers for the early identification of children who are at risk for becoming overweight at older ages. The 2000 CDC Growth Charts also include weight-for-stature charts for statures ranging from 77 to 121 cm, primarily intended for use among children from ages 2 to 5 years. A listing of the 1977 NCHS charts and the 2000 CDC charts is shown in table A.

Historical Background Anthropometric data are valuable objective indicators of attained size and physical growth in children. A variety of growth references were developed and used in the United States since the early 1900s. Most of these earlier references have considerable limitations, including lack of coverage for infants and preschool children and limited Page 1

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representation of ethnic, genetic, socioeconomic, environmental, and geographic variability (2). From 1946–1976, the Stuart/Meredith Growth Charts were widely used. These charts were derived from stature and weight measurements taken on white children living near Iowa City, Iowa, or in Boston, Massachusetts, from 1930 to 1945 (3). The sample sizes were relatively small and the smoothed percentile lines were reportedly based on mathematical approximations of curves smoothed by hand (4). Thus, the data did not represent the diversity of children residing in the United States and statistical curve-fitting procedures were not used. The impetus for the development of the 1977 NCHS Growth Charts began in 1971, when a study group sponsored by the American Academy of Pediatrics and the Maternal and Child Health Program of the Bureau of Community Health Services, U.S. Public Health Service, recommended new growth charts, based on data from the NCHS Health Examination Surveys, for the clinical assessment of infants and children (5). Subsequently, in 1974, the Food and Nutrition Board of the National Academy of Sciences made similar recommendations, emphasizing the need for new growth charts for infants and children based on nationally representative survey data, to be supplemented with data collected from infants in the Fels Longitudinal Growth Study (6). These recommendations were further supported in 1975 by a study group sponsored by the National Institute of Child Health and Human Development, National Institutes of Health (7). Growth charts for the United States were developed by NCHS when nationally representative cross-sectional survey data became available for most of the pediatric age range (8). Data from the National Health Examination Survey (NHES) II (1963–65) for ages 6–11 years, NHES III (1966–70) for ages 12–17 years, and the first National Health and Nutrition Examination Survey (NHANES) I (1971–74) for ages 1–17 years were used to develop these charts. National survey data were not available for the period from birth to 1

Table A. Charts included in the 1977 NCHS Growth Charts and in the 2000 CDC Growth Charts 1977 NCHS Growth Charts*

2000 CDC Growth Charts*

Weight-for-age Birth to 36 months 2 to 18 years

Weight-for-age Birth to 36 months 2 to 20 years

Length-for-age Birth to 36 months

Length-for-age Birth to 36 months

Weight-for-length Birth to 36 months Boys (49 to 103 cm) Girls (49 to 101 cm)

Weight-for-length Birth to 36 months Boys (45 to 103 cm) Girls (45 to 103 cm)

Head circumference-for-age Birth to 36 months

Head circumference-for-age Birth to 36 months

Stature-for-age 2 to 18 years

Stature-for-age 2 to 20 years

Weight-for-stature** Boys (90 to 145 cm) Girls (90 to 137 cm)

Weight-for-stature** Boys (77 to 121 cm) Girls (77 to 121 cm) BMI-for-age 2 to 20 years

*All charts are sex-specific. **The 1977 charts are applicable to boys with stature from 90 to 145 cm and age under 11.5 years, and to girls with stature from 90 to 137 cm and under 10.0 years of age. They are not applicable for any child showing the earliest signs of pubescence. The revised charts have no similar age or pubescence restrictions. Although the revised charts were developed for children 2 to 5 years of age, in practice they may accommodate some shorter children with chronologic ages 5.0 years and over.

year. Therefore, the national survey data were supplemented with data from the longitudinal growth study of the Fels Research Institute in Yellow Springs, Ohio. To avoid pooling multiple diverse data sets in the 1977 NCHS charts for birth to 3 years, the infant charts were based solely on the Fels data. The 14 sex-specific growth charts developed for infants birth to age 36 months and older children from ages 2 to 18 years are generally referred to as the 1977 NCHS Growth Charts (2,8,9). In 1978 CDC produced a normalized version of the NCHS curves (10,11). The World Health Organization (WHO) subsequently recommended these normalized charts for international applications (12–14). These normalized versions of the 1977 charts are thus sometimes referred to as the NCHS/WHO, CDC/WHO, or NCHS/CDC/WHO growth charts. Following the recommendation of Waterlow, et al., this version enabled the expression of body measurements in terms of standard deviations from the median or z-scores (15). Z-scores facilitate comparisons across ages and allow the mean and standard deviation to be calculated for a group of measures. Another advantage of the

normalized charts was the ability to describe the relative status of children at extremes of the distributions. Although the normalized charts allowed users a means to better quantify growth at the extremes, normalization does not refer to an improved instrument to qualify growth as ‘‘normal’’ or as a ‘‘standard’’ for growth. Both the 1977 smoothed percentiles and the 1978 normalized growth curves are growth references. They allow the growth status of a child, or a group of children, to be compared with that of a reference population. The 1978 normalized curves are similar to, but not identical with the 1977 smoothed percentiles.

Concerns Surrounding the 1977 Charts Since the development of the 1977 NCHS Growth Charts, a number of concerns have been raised about various aspects of the charts and the procedures used in their development (10,16–23). Most of these concerns centered on the infant charts and were largely associated with characteristics of the Fels data. The Fels data came from a single longitudinal study of mainly formula­

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fed, white middle-class infants in a limited geographic area of southwestern Ohio, collected 1929–75. In addition to not being from a nationally representative sample, the Fels observations were made at birth and 1 month, at 3-month intervals from 3 to 12 months, and at 6-month intervals from 12 to 36 months. These intervals may be inadequate to properly identify growth patterns during periods of rapid change. The Fels birthweights may not match more recent national birthweight distributions, and differences between recumbent length and stature may have been too large, suggesting limitations in the recumbent length data. Moreover, size and growth patterns of Fels infants may not adequately represent current growth patterns of combined breast- and formula-fed infants in the population (8,18,19,21,22). In addition, differences between the recumbent length measurements for infants from the Fels data and the stature measurements from the NCHS data sets lead to inconsistent percentile estimates from the 1977 charts when the transition is made from recumbent length to stature between 24 and 36 months of age. Other concerns included the limited ability to assess size and growth at extremes beyond the 5th and 95th percentiles, the absence of

weight-for-stature references for adolescents, and the inability to assess growth at ages 18 years and over (16).

The Revision The 1977 charts were revised in part because more recent and comprehensive national data on body measurements in U.S. children were available. After the 1977 NCHS Growth Charts were developed, additional national survey data became available from the NHANES II (1976–80) beginning at 6 months of age, and from the NHANES III (1988–94) beginning at 2 months of age (24,25). During the planning of NHANES III, increasing awareness of the concerns surrounding the 1977 NCHS Growth Charts influenced the decision to oversample children ages 2 months to 6 years. The objective of the revision process was to use improved statistical smoothing procedures, in conjunction with more comprehensive national survey data, to provide a better instrument for health care providers who evaluate the growth status of children in the United States (16). The Advance Data report summarizing the development of the revised growth charts was issued in 2000 (1). The

present report is designed to expand on the content of the initial report and provide more detailed information on the development of the revised CDC growth charts for the United States, including the process, the data sources, the statistical procedures that were followed, and the results of statistical evaluations for the revised charts.

Methods Data Sources The source of data for each growth chart is shown in table B. The primary and supplemental data sources are summarized in table C. Detailed sample sizes for the data used to create each chart, stratified by age, sex, and data source, are shown in detailed tables 1–8.

National Data The revised growth curves for the United States were developed with data collected by NCHS in five crosssectional, nationally representative health examination surveys (table C): the NHES II (1963–65) and III (1966–70), and NHANES I (1971–74),

Table B. Source of data for each growth chart Age (months) or height (cm) range

Primary data sources1

Weight-for-age

Birth to 36 months

National surveys 3–52

National birth certificate data from United States Vital Statistics2

Length-for-age

Birth to 36 months

National surveys 3–52,3

Birth certificate data from Wisconsin and Missouri State vital statistics2,4; CDC Pediatric Nutrition Surveillance System data for 0.5, 1.5, 2.5, 3.5, and 4.5 months2

Head circumference-for-age

Birth to 36 months

National surveys 3–52

Fels Longitudinal Study data2

Weight-for-length

45 to 103 cm

National surveys 3–52,5

Birth certificate data from Wisconsin and Missouri State vital statistics2

Weight-for-stature

77 to 121 cm

National surveys 3–55

None

Weight-for-age

24 to 240 months

National surveys 1–55

None

Stature-for-age

24 to 240 months

National surveys 1–5

None

Chart

BMI-for-age 1

24 to 240 months

National surveys 1–5

Survey 1 = NHES II, Survey 2 = NHES III, Survey 3 = NHANES I, Survey 4 = NHANES II, and Survey 5 = NHANES III. Excludes birthweight