Methodologic and Logistic Issues in Conducting Longitudinal Birth Cohort Studies: Lessons Learned from the Centers for Children’s Environmental Health and Disease Prevention Research

Abstract

In anticipation of the National Children’s Study, lessons can be learned from the smaller birth cohort studies conducted by five Centers for Children’s Environmental Health and Disease Prevention Research funded by the National Institute of Environmental Health Sciences and the U.S. Environmental Protection Agency. The populations studied are diverse in ethnicity and social class and reside in urban and rural environments. Although almost all of the centers chose to enroll participants through medical care facilities, they had to develop independent staffs and structures because of the overburdened medical care system. Some of the lessons learned by the centers include the importance of continuous funding, building community partnerships to conduct culturally appropriate research, hiring bilingual and bicultural staff from the community, prioritizing research goals, developing biorepositories to ensure future utility of samples, instituting quality control procedures for all aspects of specimen and data collection, maintaining frequent contact with study participants, ensuring ethical conduct of the research in a changing medical-legal climate, and communicating results in a timely and appropriate manner to participants and the wider community. All centers underestimated the necessary start-up time, staff, and costs in conducting these birth cohort studies. Despite the logistical complexity and added expenses, all centers emphasize the importance of studying the impact of environmental exposures on those children most at risk, those living in minority and low-income communities. These centers present barriers encountered, solutions found, and considerations for future research, with the hope that the lessons learned can help inform the planning and conduct of the National Children’s Study.

miRNAs Differentially Expressed by Next-Generation Sequencing in Cord Blood Buffy Coat Samples of Boys and Girls

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

“…PBR has been extensively used for pregnancy cohorts, all of which have inclusion criteria related to a specific disease process or treatment regimen. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] In this novel NCS experiment, the primary inclusion criterion was the participant's address. This article describes the recruitment and retention of NCS participants using PBR.…”

Tackling the challenges in conducting a 5‐year longitudinal study of the Healthy Beginnings Trial

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“…These retention strategies are commonly used in other studies. [4][5][6][7] We found the use of an SMS text out service 1 month before a scheduled home visit was useful in identifying changes to participants' details, identifying disconnected mobile phone numbers and allowing alternative methods of contacting participants. With the increasing use of mobile phones in the community, many participants no longer used a landline, and we found them more likely to communicate via text message.…”