Overview of National Children’s Study -Goals, Study Design, Progress

Dean Baker, MD, MPHMary CogginsUniversity of California, Irvine

November 19, 2009Orange County Vanguard Center

Topics

• National Children’s Study overview

• Rationale and key concepts

• Priority exposures and outcomes

• Benefits of the NCS

• Study design and data collection

• Neighborhood (segment) sampling in Orange County

• Data collection milestones

• Community Outreach and Engagement

Facts about the NCS

• National in scope; the study group will be representative of all US families•100,000 children & parents from 105 US counties

• Families followed from before conception or in early pregnancy until child is age 21 years

• Comprehensive study with priority exposures and outcomes

• Specimens (e.g., household dust, mother’s blood) will be stored, to answer questions in the future

Rationale for the National Children’s Study

President’s Task Force on Environmental Health and Safety Risks to Children, 2000

• Compared to adults, children may be especially vulnerable to environmental exposures – metabolism, behavior

• Exposures to some agents demonstrate potential for serious developmental effects – lead, prenatal alcohol

• Known exposures of high frequency: pesticides, violence, media

• Numerous high burden conditions with suspected environmental contribution – learning disabilities, autism, diabetes, asthma, birth defects, premature birth

• Existing research too limited in size and scope to answer these questions

• Life-course (longitudinal) design needed to correctly link multiple exposures and multiple outcomes

PL 106-310: Children’s Health Act of 2000

(a) PURPOSE — … to authorize NICHD to conduct a national longitudinal study of environmental influences (including physical, chemical, biological, and psychosocial) on children's health and development.

(b) The Director of NICHD shall establish a consortium of representatives from appropriate Federal agencies to:

(1) plan, develop, and implement a prospective cohort study, from birth to adulthood, to evaluate the effects of both chronic and intermittent exposures on child health and human development; and

(2) investigate basic mechanisms of developmental disorders and environmental factors, both risk and protective, that influence health and developmental processes…

Study Concepts

• Study high priority and burdensome conditions

• Large study population to address complex causation of important conditions (n~100,000)

• Hypothesis driven

• Exposure period begins with pregnancy

• Study environment and genetic interactions

• State-of-the-art technology

• National resource for future studies

Conceptual Model: Exposures, Interactions, Mediators, and Outcomes

Obesity and GrowthObesity and Growth

AsthmaAsthma

Neurodevelopment and BehaviorNeurodevelopment and Behavior

Pregnancy OutcomesPregnancy Outcomes

Child Health and DevelopmentChild Health and Development

InjuryInjury

Reproductive DevelopmentReproductive Development

Gene Expression

Gene Expression

HealthCare

HealthCare

Chemical ExposuresChemical Exposures

Physical ExposuresPhysical Exposures

Psychosocial ExposuresPsychosocial Exposures

Biological ExposuresBiological Exposures

GeneticsGenetics

Exposures Mediator Examples

Outcomes

Priority Exposures and Health Outcomes

Priority Exposures

Examples

Physical EnvironmentHousing quality, neighborhood

Chemical ExposuresPesticides, phthalates, heavy metals

Biologic EnvironmentInfectious agents, endotoxins, diet

GeneticsInteraction between genes and environment

Psychosocial milieu

Family structure, socio-economic status, parenting style, social networks, exposure to media and violence

Priority Health Outcomes

Examples

Pregnancy Outcomes Preterm, birth defects

Neurodevelopment and Behavior

Autism, learning disabilities, schizophrenia, conduct and behavior problems

InjuryHead trauma, injuries requiring hospitalizations

AsthmaAsthma incidence and exacerbation

Obesity and Physical Development

Obesity, diabetes, altered puberty

Potential Impact of NCS on Our Children’s Well-Being

• Identify social and environmental factors which cause or contribute to health, development, and behavior problems

• Understand the biology and genetics of health, development, and behavior

• Information on which to base decisions about policies regarding children’s health

• Economic benefits: cost avoidance

• Resource for future research

Potential Cost-Benefit Impact of NCS on Selected Health Outcomes

• Estimated annual disease burden from 10 health outcomes is approximately $395 billion• Includes direct medical spending and indirect costs from

reduced productivity

• Estimated annual reduction of $4.0–9.7 billion (1.0 –2.5%) attributable to the NCS

• Estimated annual cost of study: $0.1 billion - represents a 40:1 to 97:1 return on investment

Pivetz T et al., Battelle, April 2004

National Children’s Study - Sample Design

All Births in the Nation

Sample of Study Locations

Sample of Study Segments

Sample of Study Households

Sample of Study Women

105 Locations(counties)

Selection of neighborhoods

All eligible women in the household

~4 million births in 3,141

counties

All or a sample of households within

neighborhoods

NCS Study Locations

OrangeCounty

Selection of Segments in County

• Orange County has 45,000 births per year. The target enrollment is 250 births per year.

• Multi-stage sampling plan:

•Strata: 15 geographical strata with equal number of births

•Segment: 1,850 segments with ~ 25 births/year each

• Segments consist of contiguous US census blocks that are aggregated to have equal number of births

• The NCS Coordinating Center randomly selected one segment from each Strata

Orange County – Strata

Orange County – Sampled Segments

Single family and multi-household dwellings – some behind gates

Dense apartments – many with gates

Household Screening and Recruitment (EPSC)

• Door-to-door recruitment in segments

•Contact ~ 10,500 households

•Enroll women 18 to 49 years of age (~ 7,000)

• Follow-up of women for 5 years for pregnancy

•Intensity of follow-up depends on likelihood of pregnancy

• Women in sampled neighborhoods who become pregnant will be enrolled in study

• Household recruitment will be supplemented:

•Prenatal care providers

Schedule of Participant Visits

• 14 face-to-face contacts over 21 year study period

• Contacts most frequent early in the study

• Between visits: ongoing data collection by phone, PDA, etc.

Enrollment 3 years

1st Trimester 5 years

2nd Trimester 7 years

3rd Trimester 9 years

Delivery 12 years

6 months 16 years

12 months 20 yearsWhite = homeBlue = clinicRed = hospital

Data Collection

• Questionnaires and Interviews•Face to face

•Remote (computer, telephone, mail)

•Diaries

• Examinations •Clinical and behavioral assessments

• Biologic samples •blood, urine, cord blood, placenta, breast milk

• Environmental samples and observations •Air, dust, soil, water, home observations

T1 Home Visit – Data Collection Equipment and Supplies

Birth Visit – Data Collection at Birthing Hospitals

> 3,000 births/yr

OCVC Milestones - EPSC

• Enumeration – 10,503 dwelling units- Completed enumeration – 8,524 (82%)

• Refusal/ineligible DU – 174• With eligible female – 3,654 (37%) of DU

• Pregnancy Screen - 4,449 eligible females- Completed pregnancy screen – 3,946

• Refusal/ineligible females – 226• Eligible non-pregnant females – 2,931• Eligible Pregnant females – 70

• Pregnant Women Informed Consent• Refused – 6• Agreed to Participate – 48

OCVC Milestones – Data Collection

• T1/T2/T3 Pregnancy Visits- 27 completed & partially completed T1 visits

- 4 T2 ultrasounds

- 6 completed & partially completed T3 visits

• Father Visits- Beginning November 2009

• Birth Visits- First birth - September 17, 2009

- More in October and November

Orange County – Special Characteristics for Recruitment

• Highly populous county with many births

•45,000 births per year with NCS target of 250/year

•Births in segments are < 0.5% of births in county

• Highly diverse population with multiple primary languages and cultures

•English, Spanish, Chinese, Korean, Vietnamese, Persian

• Many restricted access communities

•Home owner associations, gated communities,locked apartment buildings

Community Outreach & Engagement Strategies

• Multi-prong approach

• Multi-level media outreach

• Neighborhood Advisory Committee (NAC) for each segment•Community group representatives and residents in

segments

• Formed or facilitated additional support groups•e.g., Korean Leadership Forum

• Monthly newsletter distributed via e-mail

Multi-Pronged Outreach Strategy

Multi-level Media Outreach

Events

Neighborhood Advisory Committees (NAC’s)

•gather unique segment characteristics

•share segment contacts

•tap into existing community networks

•help to identify key segment informants

•support continuous segment surveillance throughout recruitment

NAC - Breakfast of Champions