Gestational Age Assessment in the Ghana Randomized Air Pollution and Health Study (GRAPHS): Ultrasound Capacity Building, Fetal Biometry Protocol Development, and Ongoing Quality Control

Clinicaltrials.gov NCT01335490; http://clinicaltrials.gov/ct2/show/NCT01335490 (Archived by WebCite at http://www.webcitation.org/6UbERJNO6).