Advancing the Health of Populations Across the Life Course: 50 Years of Discoveries in the Division of Intramural Population Health Research.

In 2017, the Division of Intramural Population Health Research (DIPHR), within the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), reached a significant milestone: 50 years in existence. DIPHR celebrated this anniversary with a scientific program that reviewed past accomplishments and reflected on future directions in support of promoting the health of populations across the life course. Extending from the scientific program, the impetus of this article is to contribute to archiving and consolidating the legacy of intramural population health research at NICHD over the past 50 years. We present a brief history of the origin and evolution of intramural population health research at NICHD. Next, we conduct an empirical assessment of the scientific impact and evolving scope of this research over the past five decades and present specific key discoveries emerging from topics spanning the life course: (1) reproductive health, (2) the health of pregnant women and fetuses, (3) the health of children, and (4) associated methodologies. We also explore the Division's service to the profession in the form of mentorship of the next generation of scientists in population health research. Finally, we conclude with thoughts about future directions of population health research and reaffirm the DIPHR's commitment to promoting the health and well-being of the many populations we serve, both locally and globally.

Research Gaps in Primary Pediatric Hypertension.

Hypertension affects >40% of the US population and is a major contributor to cardiovascular-related morbidity and mortality. Although less common among children and adolescents, hypertension affects 1% to 5% of all youth. The 2017 Clinical Practice Guideline for the Diagnosis and Management of High Blood Pressure in Children and Adolescents provided updates and strategies regarding the diagnosis and management of hypertension in youth. Despite this important information, many gaps in knowledge remain, such as the etiology, prevalence, and trends of hypertension; the utility and practicality of ambulatory blood pressure monitoring; practical goals for lifestyle modification that are generalizable; the long-term end-organ impacts of hypertension in youth; and the long-term safety and efficacy of antihypertensive therapy in youth. The Eunice Kennedy Shriver National Institute of Child Health and Human Development, in collaboration with the National Heart, Lung, and Blood Institute and the US Food and Drug Administration, sponsored a workshop of experts to discuss the current state of childhood primary hypertension. We highlight the results of that workshop and aim to (1) provide an overview of current practices related to the diagnosis, management, and treatment of primary pediatric hypertension; (2) identify related research gaps; and (3) propose ways to address existing research gaps.

The National Children's Study: An Introduction and Historical Overview.

The National Children's Study (NCS) was an ambitious attempt to map children's health and development in a large representative group of children in the United States. In this introduction, we briefly review the background of the NCS and the history of the multiple strategies that were tested to recruit women and children. Subsequent articles then detail the protocols and outcomes of 4 of the recruitment strategies. It is hoped that lessons learned from these attempts to define a study protocol that could achieve the initial aims of the NCS will inform future efforts to conceptualize and execute strategies to provide generalizable insights on the longitudinal health of our nation's children.

The National Children's Study: Recruitment Outcomes Using an Enhanced Household-Based Approach.

OBJECTIVES: Ten National Children's Study (NCS) study locations with diverse demographic characteristics used an enhanced household-based recruitment (EHBR) approach to enroll preconceptional and pregnant women. Study centers used different types and dosages of community outreach and engagement (COE) activities and supplemental strategies. The goal of the study was to determine whether variability in enumeration and recruitment outcomes correlated with study location characteristics or types and dosages of COE activities (number of COE events, number of advance household mailings, total media expenditures, and total COE expenditures). METHODS: Each of the sites provided data on COE activities, protocol implementation, supplemental recruitment activities, location demographic characteristics, and enumeration/recruitment outcomes. RESULTS: COE activities varied across sites in breadth and scope. Numerous strategies were used, including media advertising, social media, participation in community-wide events, presentations to stakeholders, and creation of advisory boards. Some sites included supplemental recruitment efforts. EHBR sites enrolled 1404 women at the initial pregnancy screening. No significant relationships were found between study location demographic characteristics or between the types and dosages of COE activities and recruitment outcomes. CONCLUSIONS: Probability sampling for a long-term study requires a positive image with stakeholders and within communities; this requirement may be especially true for door-to-door recruitment. EHBR sites successfully recruited a representative sample of preconceptional and pregnant women. Sites reported implementing similar COE activities but with varying dosage and cost; however, analyses did not support a benefit of COE strategies on study recruitment.

The National Children's Study: Early Recruitment Outcomes Using the Direct Outreach Approach.

OBJECTIVE: In 2009, the National Children's Study (NCS) Vanguard Study tested the feasibility of household-based recruitment and participant enrollment by using a birth rate probability sample. In 2010, the NCS Program Office launched 3 alternative recruitment methods. We tested whether direct outreach (DO) recruitment could be a more efficient strategy to recruit women of child-bearing age. METHODS: The NCS DO recruitment approach recruited women, 18 to 49 years, who were pregnant or trying to conceive using passive recruitment methods emphasizing broad community outreach and engagement to create study awareness. Study mailings to listed households included a pregnancy screening questionnaire to identify potentially eligible women from selected neighborhoods to contact the study center. Unique features of this recruitment approach included the following: (1) expansion of selected neighborhoods to maximize potential participant recruitment and enrollment while minimizing in-person participant contact and (2) offering 2 levels of study participation distinguished by data collection intensity. RESULTS: Ten study centers listed 255 475 geographically eligible households for contact representing, on average, 3.3% of households per Primary Sampling Unit. A total of 19 354 women were identified for screening, and 17 421 completed a pregnancy screener representing 6.8% of eligible households. Study-eligible pregnant women were older, more educated, and less likely to be Hispanic than the general population. Only 16% (2786) of 17 421 screened women were study-eligible, and 81.1% of these 2786 women consented to participate. CONCLUSIONS: Although feasible, the DO approach recruited a sample of study-eligible pregnant women significantly different from the population. This recruitment approach was labor intensive for the yield of enrolled women.

The National Children's Study: Recruitment Outcomes Using the Provider-Based Recruitment Approach.

OBJECTIVE: In 2009, the National Children's Study (NCS) Vanguard Study tested the feasibility of household-based recruitment and participant enrollment using a birth-rate probability sample. In 2010, the NCS Program Office launched 3 additional recruitment approaches. We tested whether provider-based recruitment could improve recruitment outcomes compared with household-based recruitment. METHODS: The NCS aimed to recruit 18- to 49-year-old women who were pregnant or at risk for becoming pregnant who lived in designated geographic segments within primary sampling units, generally counties. Using provider-based recruitment, 10 study centers engaged providers to enroll eligible participants at their practice. Recruitment models used different levels of provider engagement (full, intermediate, information-only). RESULTS: The percentage of eligible women per county ranged from 1.5% to 57.3%. Across the centers, 3371 potential participants were approached for screening, 3459 (92%) were screened and 1479 were eligible (43%). Of those 1181 (80.0%) gave consent and 1008 (94%) were retained until delivery. Recruited participants were generally representative of the county population. CONCLUSIONS: Provider-based recruitment was successful in recruiting NCS participants. Challenges included time-intensity of engaging the clinical practices, differential willingness of providers to participate, and necessary reliance on providers for participant identification. The vast majority of practices cooperated to some degree. Recruitment from obstetric practices is an effective means of obtaining a representative sample.

Multilevel Provider-Based Sampling for Recruitment of Pregnant Women and Mother-Newborn Dyads.

OBJECTIVE: In 2010, the National Children's Study launched 3 alternative recruitment methods to test possible improvements in efficiency compared with traditional household-based recruitment and participant enrollment. In 2012, a fourth method, provider-based sampling (PBS), tested a probability-based sampling of prenatal provider locations supplemented by a second cohort of neonates born at a convenience sample of maternity hospitals. METHODS: From a sampling frame of 472 prenatal care provider locations and 59 maternity hospitals, 49 provider and 7 hospital locations within or just outside 3 counties participated in study recruitment. During first prenatal care visits or immediately postdelivery at these locations, face-to-face contact was used to screen and recruit eligible women. RESULTS: Of 1450 screened women, 1270 were eligible. Consent rates at prenatal provider locations (62%-74% by county) were similar to those at birth locations (64%-77% by county). During 6 field months, 3 study centers enrolled a total prenatal cohort of 530 women (the majority in the first trimester) and during 2 months enrolled a birth cohort of an additional 320 mother-newborn dyads. As personnel became experienced in the field, the time required to enroll a woman in the prenatal cohort declined from up to 200 hours to 50 to 100 hours per woman recruited. CONCLUSIONS: We demonstrated that PBS was feasible and operationally efficient in recruiting a representative cohort of newborns from 3 diverse US counties. Our findings suggest that PBS is a practical approach to recruit large pregnancy and birth cohorts across the United States.

The Experience of Direct Outreach Recruitment in the National Children's Study.

OBJECTIVE: Few studies have reported the outcome of direct outreach methods for recruitment of research participants in population-based samples. We describe the relationship of outreach strategies that are tailored to specific community factors to recruitment and consent outcomes in 10 National Children's Study direct outreach study locations (all were single counties). METHODS: Each study center collected data from a target population of women who resided in selected county segments that were sampled based on a geographic area probability sampling design. Based on county characteristics of the 10 study locations, each study center used site-specific marketing approaches (direct mail, mass media, provider referrals, social networking) to recruit study participants. Recruitment success was measured by the number of recruited women as well as by a qualitative assessment of the effectiveness of various recruitment methods. RESULTS: The number of women who consented varied from 67 to 792. The majority of women were pregnant at the time of consent. Community awareness varied from <1% to 70%. Although no significant associations were found between community characteristics and recruitment success, we found that certain types of outreach strategies enhanced recruitment. CONCLUSIONS: In a small sample of 10 US counties, recruitment success was not associated with community characteristics. It was, however, associated with certain types of outreach strategies that may be more effective in close-knit communities.

Why should there be an NICHD?

In its nearly 5 decades of existence, the Eunice Kennedy Shriver National Institute of Child Health and Human Development has expended $23 billion in conducting and supporting research and translating discoveries to practice. The resulting dramatic impact on peoples' lives and improved health for children and families, chronicled herein, are a testament to the benefits of having this institute at the National Institutes of Health.