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

Abstract

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 National Children's Study Archive Model: A 3-Tier Framework for Dissemination of Data and Specimens for General Use and Secondary Analysis

“…Recruitment under the three ARS strategies ended in February 2012. The ARS was followed in June 2012 by another substudy, the Provider-Based Sampling (PBS) Substudy, which was conducted in three study locations ( 6 ). Overall, the PBS strategy proved most effective and cost efficient ( 7 ).…”

Comparison of Recruitment Strategy Outcomes in the National Children’s Study

“…When preliminary analysis showed that the PBR strategy achieved the greatest efficiency of operations, a provider-based sampling (PBS) strategy was designed as a fourth ARS. 24 In contrast to the first 4 strategies that relied on geographic area sampling, the PBS sampled prenatal care provider locations and birthing hospitals that were used by residents in the PSU and then further sampled women at these provider locations for recruitment. The PBS, therefore, consisted of 2 recruitment subcohorts, a prenatal cohort in which pregnant women were sampled and recruited from prenatal care provider offices at their first prenatal visit and a hospital cohort in which women and newborns were sampled and recruited at the time of delivery from hospitals.…”