Researchers are concerned about factors that influence participants’ decisions to participate and continue in longitudinal research studies, but few empirical studies have examined the role of participant motivation and study experiences. We analyzed data from 4,216 participants enrolled in the National Children’s Study Vanguard Study, a series of pilot studies for a large-scale epidemiological cohort study of children and their mothers. Findings indicated most participants joined the NCS for altruistic reasons. While our data suggest some association between reasons for joining a study and retention, they are not the strongest predictors for retention after controlling for participant demographics. Continued participation in the study was associated with demographic factors and having a positive experience in the NCS.

Aim: Among adolescents, poisoning is a leading cause of injury mortality in the United States. This study describes the epidemiology of poisonings, intoxication, and maladaptive effects of drugs among adolescents age 10-19 years in a large city.Methods: An injury surveillance system used records at seven hospitals, medical examiner records, and vital records over a two year period.Results: Of 633 cases (618 injuries/100 000/year), 6% were unintentional, 36% self-inflicted, 41% alcohol intoxication, and 15% maladaptive effects of drugs. Alcohol was involved in 45% of cases, 23% illegal drugs, 23% nonprescription drugs, 19% prescription drugs; 19% involved more than one substance. Hospitalization was required in 20%; 8% transferred to another hospital; one died from intoxication. The authors found high rates of self-inflicted poisoning, intoxication, and maladaptive effects of drugs among this urban population.Conclusion: The study highlights the need to broadly define poisonings among adolescents and the challenge of assessing intent in some cases.

Background: In the United States, infant-parent bed sharing is a controversial and poorly understood practice. Proponents site potential advantages such as increases in bonding and facilitation of breastfeeding, whereas opponents site potential increases in risks of suffocation and sudden infant death syndrome, particularly among mothers who smoke. Few studies have examined normative practices in low-income populations.Objectives: To describe sleep practices in a cohort of infants born to predominantly low-income, inner-city mothers, to examine stability in-sleep practices during the first 7 to 12 months of life, and to identify factors associated with bed sharing.Design and Setting: Prospective birth cohort study in the District of Columbia, with recruitment taking place between August 1995 and September 1996 and follow-up from November 1995 to September 1997.Participants: Maternal-infant pairs were systematically selected from 3 hospitals. We interviewed 394 mothers shortly after delivery and at 3 to 7 months post partum. Of these, 369 were interviewed again at 7 to 12 months post partum.Main Outcome Measure: Usual bed sharing.Results: At age 3 to 7 months (mean age, 129 days), 201 infants (51%) usually slept alone and 191 (48%) usually slept in a bed with a parent or other adult. Similarly, at age 7 to 12 months (mean age, 262 days), 190 infants (51%) usually slept alone and 175 (47%) usually slept in a bed with a parent or other adult. Of the infants who slept with a parent or other adult at age 3 to 7 months 75% continued to do so at age 7 to 12 months. Similarly, of infants who usually slept alone at age 3 to 7 months, only 22% were reported to be usual bed sharers at age 7 to 12 months. In multivariate analyses, factors associated with bed sharing at both follow-up interviews included single marital status of the mother (first interview: odds ratio [OR] = 1.90; 95% confidence interval [ CI 1, 1.11-3.27; second interview: OR= 1.81; 95% CI, 1.02-3.25) and I or more moves since the birth of the infant (first interview: OR= 1.82; 95% CI, 1.10-3.01; second interview: OR= 1.73; 950% CI, 1.05-2.86). Breastfeeding and household crowding were not significantly associated with bed sharing.Conclusions: Bed sharing was common in this inner-city population, and sleep practices were relatively stable during the first 7 to 12 months of life. These findings underscore the need for additional research clarifying, the benefits and risks of bed sharing.

Context. Although the proportion of US children who are appropriately immunized increased dramatically in the past decade, rates remain suboptimal among low-income, inner-city youth. Timely initiation of immunization is an important predictor of immunization status later in childhood; however, prospective studies identifying predictors of initiation are lacking.Objectives. The objectives of this study were to: 1) describe immunization patterns in a cohort of infants born to predominantly low-income, inner-city mothers; 2) identify determinants, as measured at birth, of immunization status at 3 and 7 months of age; and 3) identify determinants of continuation of immunization among those who initiate immunization by 3 months of age.Design. Prospective, birth cohort study.Methods. Maternal/infant dyads were systematically selected from 3 District of Columbia hospitals between August 1995 and September 1996. Three hundred sixty-nine mothers were interviewed shortly after delivery, at 3 to 7 months postpartum, and at 7 to 12 months postpartum. Medical records were reviewed at all reported sites of care for 324 (88%) infants. Vaccinations assessed included diphtheria, tetanus, and pertussis; polio; and Haemophilus influenzae type B. Multivariate logistic regression analyses were used to determine factors associated with immunization status of infants at 3 and 7 months of age.Results. At 3 months of age, 75% of infants were up-to-date (UTD) versus only 41% at 7 months. In adjusted analyses, baseline factors associated with being UTD at 3 months included enrollment in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) during pregnancy, intention to breastfeed, and presence of the infant's grandmother in the household. Infants were less likely to be UTD if their mothers perceived higher barriers to immunization. Baseline factors associated with being UTD at 7 months included lower birth order and maternal employment. Among the subset of infants who were UTD at 3 months, only 53% remained UTD at 7 months. Factors measured at the first follow-up interview that were associated with continuation of immunization at 7 months included maternal employment and lower perceived barriers.Conclusions. Immunization rates during the first 7 months of life were low in this inner-city population. Factors associated with immunization status that are potentially amenable to change included perceived barriers to immunization and enrollment in WIC during pregnancy.

The Epidemiology of Infant Colonization and Early-Onset Group B Streptococcal(GBS) Disease in the U.S., a Multi-Center Study from 1995-97

Antibiotic Susceptibility of Invasive Group B Streptococci from Neonates with Early-Onset Disease - A Multi Center Study 1995-97

Determinants of Early-Onset Group B Streptococcal Disease - A Multi Center Case-Control Study

Despite the profusion of promising new vaccines against illnesses prevalent in developing countries, uncertainties about the balance between costs and benefits of new vaccines have retarded their use in public health practice. Conventional prelicensure trials of vaccine protection exacerbate these uncertainties by focusing on measurement of vaccine efficacy--the performance of a vaccine under idealized conditions. Vaccine effectiveness trials provide a more pragmatic perspective by addressing the performance of a vaccine under the ordinary conditions of a public health program, by capturing direct as well as indirect effects of vaccination, and by comprehensively addressing outcomes of public health concern. The use of effectiveness trials should enable more rational triaging of new vaccines for developing countries and may accelerate the introduction of new vaccines into public health practice by resolving speculative debates about practical costs and benefits.

Annals of the New York Academy of SciencesVolume 754, Issue 1 p. 255-266 Interactions between PRP-T Vaccine against Haemophilus influenzae Type b and Conventional Infant Vaccines Lessons for Future Studies of Simultaneous Immunization and Combined Vaccines JOHN CLEMENS, JOHN CLEMENS Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this authorRUTH BRENNER, RUTH BRENNER Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this authorMALLA RAO, MALLA RAO Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this author JOHN CLEMENS, JOHN CLEMENS Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this authorRUTH BRENNER, RUTH BRENNER Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this authorMALLA RAO, MALLA RAO Division of Epidemiology, Statistics, and Prevention Research National Institute of Child Health and Human Development Bethesda, Maryland 20892Search for more papers by this author First published: May 1995 https://doi.org/10.1111/j.1749-6632.1995.tb44458.xCitations: 10AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume754, Issue1Combined Vaccines and Simultaneous Administration: Current Issues and PerspectivesMay 1995Pages 255-266 RelatedInformation