American Journal of

American Journal of

ISSN 0002-9262

EPIDEMIOLOGY Volume 137

Published by The Johns Hopkins University School of Hygiene and Public Health

Number 3 Sponsored by the Society for Epidemiologic Research

February 1, 1993

ORIGINAL CONTRIBUTIONS 263

270 281 292

301 311

318

331 342

355

366 373 381

Vasectomy and Prostate Cancer in US Blacks and Whites. Richard B. Hayes, Linda M. Pottern, Raymond Greenberg, Janet Schoenberg, G. Marie Swanson, Jonathan Lift, Ann Grossbart Schwartz, Linda Morris Brown, and Robert N. Hoover Farming and Prostate Cancer Mortality. Howard Morrison, David Savitz, Robert Semenciw, Barbara Hulka, Yang Mao, Deirdre Morison, and Donald Wigle Cigarette Smoking and the Risk of Endometrial Cancer. Louise A. Brinton, Rolland J. Barrett, Michael L. Berman, Rodrigue Mortel, Leo B. Twiggs, and George D. Wilbanks Association between Plasma Fibrinogen Concentration and Five Socioeconomic Indices in the Kuopio Ischemic Heart Disease Risk Factor Study. Thomas W. Wilson, George A. Kaplan, Jussi Kauhanen, Richard D. Cohen, Melien Wu, Riitta Salonen, and Jukka T. Salonen Secular Trends in Coronary Heart Disease Mortality in Norway, 1966-1986. Jan Marcus Sverre Prevalence of Cardiovascular Diseases among Older Adults: The Cardiovascular Health Study. Maurice B. Mittelmark, Bruce M. Psaty, Pentti M. Rautaharju, Linda P. Fried, Nemat 0. Borhani, Russell P. Tracy, Julius M. Gardin, and Daniel H. O'Leary for the Cardiovascular Health Study Collaborative Research Group Depressive Symptoms and Headaches in Relation to Proximity of Residence to an Alternating-Current Transmission Line Right-of-way. Charles Poole, Robert Kavet, Donna P. Funch, Karen Donelan, Jonathan M. Charry, and Nancy A. Dreyer Outdoor Air Temperature and Mortality in the Netherlands: A Time-Series Analysis. Anton E. Kunst, Caspar W. N. Looman, and Johan P. Mackenbach Incidence of and Risk Factors for Falls and Injurious Falls among the Communitydwelling Elderly. Jennifer L. O'Loughlin, Yvonne Robitaille, Jean-Frangois Boivin, and Samy Suissa Malnutrition, Cell-mediated Immune Deficiency, and Diarrhea: a Community-based Longitudinal Study in Rural Bangladeshi Children. Abdullah H. Baqui, Robert E. Black, R. Bradley Sack, H. R. Chowdhury, M. Yunus, and A. K. Siddique Exposure to Children and Risk of Active Trachoma in Tanzanian Women. Nathan Congdon, Sheila West, Susan Vitale, Sidney Katala, and B. B. 0. Mmbaga Evaluation of a Method for Detecting Aberrations in Public Health Surveillance Data. Donna F. Stroup, Melinda Wharton, Karen Kafadar, and Andrew G. Dean ERRATUM

Founded 1920 by W. H. Welch and W. H. Howell as the American Journal of Hygiene

The Johns Hopkins Center for Clinical Trials SHORT

COURSE

Coordination and Monitoring of Clinical Trials Baltimore, Maryland Thursday - Friday July 8-9, 1993 Of particular interest to those who expect to take leadership roles in future multicenter trials. Topics to be addressed include, among others: •

Coordinating centers for multicenter trials •

Personnel training and certification

•

Coordination of clinical center activities

•

Quality assurance and monitoring

•

Specialized resource centers

•

Monitoring for treatment benefit or harm

Course director: Barbara S. Hawkins, Ph.D. Associate Professor of Ophthalmology Associate Director, The Johns Hopkins Center for Clinical Trials For information, write or telephone: Office of Continuing Education, Turner 20, 720 Rutland Avenue, The Johns Hopkins Medical Institutions, Baltimore, Maryland 21205; (410) 955-2959. AM A Category 1 credits.

The Stanley S. Schor Visiting Scholar Program Sponsored by Merck Research Laboratories Merck Research Laboratories request applications for the Stanley S. Schor Visiting Scholar program. Distinguished statisticians, biostatisticians, health economists, and epidemiologists are invited to spend a period of 6-12 months (starting In late 1994 or early 1995) at Merck The visiting scholar will be expected to collaborate with Merck statisticians as well as medical and biological investigators, and to teach a course or conduct a seminar series It is anticipated that the visiting scholar will be involved closely with at least one project in biopharmaceutical research, e.g. safety assessment clinical pharmacology, clinical trials, epidemiology, health economics. Merck Research Laboratories has facilities both in northern New Jersey (Rahway) and immediately outside Philadelphia, PA (West Point, Blue Bell). There are approximately seventy statisticians throughout the company conducting research relating to the various steps in drug development Merck statisticians traditionally combine collaborative research with medical or biological investigators in applied

methodology research including publications, participation in conferences and activities in professional associations Candidates for this program should have an outstanding research record in biostatistics and /or epidemiology including both publications in statistical methodology and applied research. Applications should include: CV and a letter of intent describing what a visiting scholar would hope to achieve during a visit at Merck. Send applications to Dr. W. J. Shih, Chair, Stanley S. Schor Program Search Committee, Merck Research Laboratories, WBD-400, Merck & Co, Inc., P.O. Box 2000, Rahway, NJ 07065-0914. Deadline for applications: September 30,1993

MERCK Research Laboratories

XXVm GRADUATE SUMMER SESSION IN EPIDEMIOLOGY Presented by the University of Michigan School of Public Health July 11-30,1993

THREE WEEK COURSES •Epidemiology of Injuries •New Concepts in Cancer Epidemiology •Microcomputer Applications in Epidemiology

•Applied Epidemiology for Health Practitioners •Fundamentals of Epidemiology •Fundamentals of Biostatistics

ONE WEEK COURSES •Basic Concepts of Clinical Epidemiology •Clinical Trials - Design and Conduct •Clinical Trials - Analytic Methods

•Analysis of Epidemiologic Measures •Introduction to the Logistic Model •Analysis of Survival/Follow-up Data

•Environmental Exposure Assessment •Occupational Epidemiology •Environmental Epidemiology

•Nutrition Assessment •Nutritional Epidemiology •Nutritional Intervention

•Pharmacoepidemiology •Substance Abuse •Sexually Transmitted Diseases and HIV

•Epidemiologic Issues in Women's Health: Controversies and Challenges

•Update in Infectious Diseases •Infection Control •Methods in Medical Quality Assessment

•Epidemiology of Mental Disorders •Epidemiology of Aging •Behavioral Modification •Epidemiology and Health Policy

•Analysis of Sample Survey Data

For application and information contact: Dr. David Schottenfeld or Jody Gray, Administrative Coordinator Graduate Summer Session in Epidemiology The University of Michigan School of Public Health 109 S. Observatory Street Ann Arbor, MI 48109-2029 USA Telephone: (313)764-5454

Distinguished faculty have been selected from Universities throughout the United States and Canada

The Graduate Summer Session welcomes national and international health professionals

The University of Michigan is a non-discriminating/affirmative action institution

3 Weeks with 23 courses in quantitative medical research Rotterdam, The Netherlands, August 16 - September 3, 1993 The Erasmus Summer Programme 1993 offers 23 courses on the principles and methods of quantitative research in medicine and public health. The courses are meant for those involved in quantitative research, including clinicians, public health practitioners, research officers, epidemiologists, biostatisticians and geneticists. The first week provides introductory courses, the second week methodology courses and the third week advanced courses. It is possible to subscribe for 1, 2 or 3 weeks in one discipline or to mix and match courses from different disciplines in order to design your own individual programme.

Epidemiology

Human Genetics

August 16 - August 20 • Principles of epidemiologic research. • Introduction to data analysis.

August 16 - August 20 • Clinical and population genetics. • Practicum clinical and population genetics.

August 23 - August 27 • Conducting epidemiologic research. • How to write a medical article. August 30 - September 3 • Advanced study design. • Advanced statistical methods.

August 23 - August 27 • Genetic epidemiology. • Statistical aspects of genetics. August 30 - September 3 • Advanced statistical methods.

Clinical Research

Health Services Research

August 16 - August 20 • Principles of research in medicine. • Epidemiology for clinicians. • Research in general practice August 23 - August 27 • Methods of clinical research. • Clinical decision analysis. August 30 - September 3 • Human drug research. • Design, conduct and analysis of clinical trials.

August 16 - August 20 • Introduction to health services research. • Policy analysis in health care. August 23 - August 27 • Methods of public health research. • Health economics. • Medical technology assessment.

Programme and further Information Call, fax or write for the brochure with detailed information on the courses, the extracurricular programme and accomodatlons to Sandra Overdljk, Office for Post Graduate Medical Education, Erasmus University Medical School. Phono+31 (0)10 408 7879 Fax+31 (0)10 436 7271 Write P.O. Box 1738, 3000 DR Rotterdam The Netherlands

August 30 - September 3 • Health status measurement. • Epidemiology and health policy.

The Erasmus Summer Programme Faculty David Clayton, University of Cambridge, Michael Hills, London School of Hygiene; Paul Kind, University of York; Bradford Klrkman-Ljff, Arizona State University; Stephen Lock, ed.em British Medical Journal; Jacobus Lubsen, SOCAR, Nyon; Olii Miettmen, McGill University, Montreal; Louise Gunning, Jan Tijssen, University of Amsterdam; Adam Cohen, Job Kievit, University of Leiden; Andre Knottnerus, University of Limburg; Gouke Bonsel, Eddy van Doorslaer, Cornelia van Duyn, Tom van der Grinten, Diederick Grobbee, Arno Hoes, Albert Hofman, Dick Llndhout, Paul van der Maas, Johan Mackenbach, Ane Man in 't Veld, Frans Rutten, Lodewijk Sandkuijl, Theo Stijnen, Ronald Stolk, Wynand van der Ven, Erasmus University Rotterdam.

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SURVIVAL f UNCTION - - HEART TRANSPLANT STUDY

- - - -

45OTLESS OVER 45

.750-

.500-

250-

0-

4

10

tS

20

25

30

35

40

45

TIME IN DAYS

Survival plot generated from Survival Analysis with Covariates program (2L). Survival functions are plotted for subjects from two different age groups: 45 or less and over 45.

Group Means --Symbols I w j o n a i e

• • s h o d f c r « . h«

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American Journal of

Founded 1920 by W. H. Welch and

EPIDEMIOLOGY BOARD OF OVERSEERS ALFRED SOMMER,

Chairman LEON GORDIS CHARLES H. HENNEKENS ALLYN W. KIMBALL NOEL R. ROSE LYNN ROSENBERG

W. H. Howell as the American Journal of Hygiene

BOARD OF EDITORS MOYSES SZKLO,

TECHNICAL EDITORS

ADRIAN M. OSTFELD,

Editor-in-Chief

SANDRA L. BRYANT JANET M. MCNAUGHTON SUSAN G. MURRAY AMY W. REDMON

Editor Emeritus

GEORGE W. COMSTOCK,

Editor-in-Chief Emeritus HAROUTUNE K. ARMENIAN TERRI H. BEATY PETER BURNEY TOM D. Y. CHIN JANET R. DALING C. E. DAVIS ALLAN DONNER FRED EDERER GARY D. FRIEDMAN MARY MONK

DIANA B. PETITTI JONATHAN M. SAMET W. EUGENE SANDERS, JR. DAVID A. SAVITZ MEIR J. STAMPFER DAVID B. THOMAS STEPHEN D. WALTER

ADMINISTRATIVE ASSISTANT HARRIETT TELLJOHANN ADMINISTRATIVE SECRETARIES ANN TEN EYCK DUNBAR SHAWNISE F. SMITH

MANAGING EDITOR EARLE V. HART, JR.

SECRETARY

ASSOCIATE MANAGING EDITOR

DARCELL C. VINSON

CHRISTOPHER T. GEORGE SUBSCRIPTION MANAGER SANDRA ADAMS

ASSOCIATE EDITORS ANDERS AHLBOM, Stockholm, Sweden JORDI ALONSO, Barcelona, Spain JOSEP M. ANTO, Barcelona, Spain

BEN ARMSTRONG, Montreal, Canada PETER H. BENNETT, Phoenix, AZ ROBERTO BERTOLLINI, Rome, Italy AARON BLAIR, Bethesda, MD STEVEN N. BLAIR, Dallas, TX MARTIN J. BLASER, Nashville, TN ERIC BOERWINKLE, Houston, TX PHILIP S. BRACHMAN, Atlanta, GA LOUISE A. BRINTON, Bethesda, MD SHELLEY B. BULL, Toronto, ON, Canada GARY A. CHASE, Baltimore, MD HARVEY CHECKOWAY, Seattle, WA GRAHAM A. COLDITZ, Boston, MA JAMES W. CURRAN, Atlanta, GA A. MICHAEL DAVIES, Jerusalem, Israel ALAN R. DYER, Chicago, IL PHILIP E. ENTERLINE, Pittsburgh, PA MANNING FEINLEIB, Bethesda, MD W. DANA FLANDERS, Atlanta, GA AARON FOLSOM, Minneapolis, MN LINDA P. FRIED, Baltimore, MD PETER J. GERGEN, Hyattsville, MD W. PAUL GLEZEN, Houston, TX ROBERT J. GOLDBERG, Worcester, MA MARC T. GOODMAN, Honolulu, HI SAXON GRAHAM, Buffalo, NY RAYMOND S. GREENBERG, Atlanta, GA SANDER GREENLAND, LOS Angeles, CA STEPHEN C. HADLER, Atlanta, GA ROBERT W. HALEY, Dallas, TX M. ELIZABETH HALLORAN, Atlanta, GA JEAN H. HANKIN, Honolulu, HI

ROBERT A. HIATT, Oakland, CA THEODORE R. HOLFORD, New Haven, CT WALTER W. HOLLAND, London,

England DONALD R. HOOVER, Baltimore, MD HAROLD W. JAFFE, Atlanta, GA ULRICH KEIL, Bochum, Germany MUIN J. KHOURY, Atlanta, GA ALLYN W. KIMBALL, Baltimore, MD LAURENCE N. KOLONEL, Honolulu, HI LEWIS KULLER, Pittsburgh, PA CARLO LA VECCHIA, Milan, Italy FRANK E. LUNDIN, Rockville, MD JACK S. MANDEL, Minneapolis, MN JAMES R. MARSHALL, Buffalo, NY JAMES E. MAYNARD, Atlanta, GA JOSEPH K. MCLAUGHLIN, Bethesda, MD L. JOSEPH MELTON III, Rochester, MN DAVID L. MILLER, London, England PATRICIA P. MOLL, Ann Arbor, MI ARNOLD S. MONTO, Ann Arbor, MI HAL MORGENSTERN, LOS Angeles, CA EVE K. MOSCICKI, Rockville, MD JAMES W. MOSLEY, LOS Angeles, CA NANCY ELSA MUELLER, Boston, MA

C. S. Mum, Lyon, France KENRAD E. NELSON, Baltimore, MD F. JAVIER NIETO, Baltimore, MD ABRAHAM M. Y. NOMURA, Honolulu, HI RALPH S. PAFFENBARGER, JR.,

Stanford, CA PAOLO PASQUINI, Rome, Italy NEIL PEARCE, Wellington, New Zealand MARVIN J. PODGOR, Bethesda, MD CHARLES POOLE, Cambridge, MA

Ross PRENTICE, Seattle, WA WILLIAM C. REEVES, Atlanta, GA ARTHUR L. REINGOLD, Berkeley, CA JAMES M. ROBINS, Boston, MA ELAINE RON, Bethesda, MD LYNN ROSENBERG, Brookline, MA BERNARD ROSNER, Boston, MA JUKKA T. SALONEN, Kuopio, Finland DALE P. SANDLER, Research Triangle

Park, NC RODOLFO SARACCI, Lyon, France WILLIAM SCHAFFNER, Nashville, TN MARK H. SCHIFFMAN, Bethesda, MD WILLIAM J. SCHULL, Houston, TX CHRISTOPHER T. SEMPOS, Hyattsville, MD A. RICHEY SHARRETT, Bethesda, MD RICHARD B. SHEKELLE, Houston, TX STEPHEN SIDNEY, Oakland, CA JACK SIEMIATYCKI, Laval, QU, Canada DAVID SISCOVICK, Seattle, WA PAUL D. SORLIE, Bethesda, MD J. MICHAEL SPRAFKA, Minneapolis, MN JANET L. STANFORD, Seattle, WA CLADD E. STEVENS, New York, NY JAMES M. TIELSCH, Baltimore, MD HERMAN A. TYROLER, Chapel Hill, NC CESAR VICTORA, Pebtas, Brazil ROBERT B. WALLACE, Iowa City, IA ALLEN J. WILCOX, Research Triangle

Park, NC WALTER WILLETT, Boston, MA WARREN WINKELSTEIN, JR., Berkeley, CA ROBERT F. WOOLSON, Iowa City, IA

AMERICAN JOURNAL OF EPIDEMIOLOGY (ISSN 0002-9262) is published twice monthly for $190.00 (Domestic) and $198.00 (Foreign) per year by The Johns Hopkins University School of Hygiene and Public Health, 615 N. Wolfe St., Baltimore, MD 21205. Second-class postage paid at Baltimore, MD, and additional mailing offices. Postmaster Send address changes to: AMERICAN JOURNAL OF EPIDEMIOLOGY, 2007 E. Monument St, Baltimore, MD 21205-2216. Sponsored by the Society for Epidemioiogic Research. Supported in part by a bequest from the DeLamar Fund. Editorial Office telephone no.: 410-955-3441; fax: 410-9550344. Printed by Waverly Press, 1314 Guilford Ave., Baltimore, MD 21202-3995.