About the CPP

The Collaborative Perinatal Project (CPP), also known as the National Collaborative Perinatal Project (NCPP), was a landmark prospective birth cohort study conducted from 1959 to 1974 under the auspices of the National Institute of Neurological Diseases and Stroke (NINDS). Twelve university-affiliated medical centers across the United States enrolled approximately 60,000 pregnancies and followed children from the prenatal period through age 7–8, producing one of the most comprehensive developmental datasets ever assembled.

The study collected detailed information on maternal health, prenatal care, labor and delivery, neonatal outcomes, and child development. Its cognitive testing battery was exceptionally thorough: children received the Stanford-Binet IQ test at age 4 (along with the ITPA Auditory-Vocal Association test) and the full Wechsler Intelligence Scale for Children (WISC) at age 7, along with the Wide Range Achievement Test (WRAT) and Bender-Gestalt test. The dataset also includes extensive family structure, with 8,772 mothers contributing two or more children, yielding 19,966 children in sibling families and 640 twin pairs suitable for behavior-genetic and within-family designs.

The CPP produced foundational publications in developmental psychology and perinatal epidemiology and has been called a “national treasure” for perinatal epidemiology (Hardy, 2003).

About This Release

Despite its extraordinary scope, the CPP has been severely underutilized in modern research because the only documentation was scanned microfiche of 1970s-era typewritten codebooks—over 5,000 pages with no digital index—and the data is stored in archaic fixed-width and punch-card formats with no variable names or metadata.

This release is a comprehensive rescue and modernization of the CPP dataset. It provides:

• Machine-readable versions of every documented variable from both source files
• Named-column CSVs for all 309 master card types (6.1 million records)
• 31 standalone datasets (1,515,805 records) parsed from the NARA/NBER Johns Hopkins collection
• Publication-quality codebooks at the variable and field level
• OCR transcriptions of all 19 documentation volumes (~5,000 pages)
• NLSYLinks-style kinship tables with twin zygosity classification
• Pre-computed derived variables for common analytical tasks
• Identification and correction of six mislabeled variables in the original data files
• Survey weights enabling nationally representative estimation

Collaborating Institutions

• Boston Lying-In Hospital (Harvard Medical School), Boston, MA
• Children's Hospital (University of Buffalo), Buffalo, NY
• Charity Hospital (Tulane & LSU), New Orleans, LA
• Columbia-Presbyterian Medical Center, New York, NY
• Johns Hopkins Hospital, Baltimore, MD
• Medical College of Virginia (Virginia Commonwealth), Richmond, VA
• University of Minnesota Hospital, Minneapolis, MN
• Metropolitan Hospital (New York Medical College), New York, NY
• University of Oregon Medical School, Portland, OR
• Pennsylvania Hospital (University of Pennsylvania), Philadelphia, PA
• Providence Lying-In Hospital (Brown University), Providence, RI
• University of Tennessee / Gailor Hospital, Memphis, TN

Key Publications

The CPP generated over 700 publications. The foundational books are:

• Niswander, K. R. & Gordon, M. (1972). The Women and Their Pregnancies. W. B. Saunders.
• Broman, S. H., Nichols, P. L., & Kennedy, W. A. (1975). Preschool IQ: Prenatal and Early Developmental Correlates. Erlbaum.
• Broman, S. H., Nichols, P. L., Shaughnessy, P., & Kennedy, W. (1987). Retardation in Young Children. Erlbaum.
• Hardy, J. B., Drage, J. S., & Jackson, E. C. (1979). The First Year of Life. Johns Hopkins University Press.
• Myrianthopoulos, N. C. (1985). Malformations in Children from One to Seven Years. Alan R. Liss.
• Hardy, J. B. (2003). The Collaborative Perinatal Project: Lessons and legacy. Annals of Epidemiology, 13(5), 303–311.

Paper & Citation

If you use this dataset, please cite:

Lasker, J. (2026). The Collaborative Perinatal Project: A Modern Data Release. OSF Preprints. https://osf.io/4tna9

OSF Project: https://osf.io/d3f9k/ — data release archive and papers
Preprint: OSF Preprints

Notable papers using CPP data include:

• Willerman, L., Naylor, A. F., & Myrianthopoulos, N. C. (1970). Intellectual development of children from interracial matings. Science, 168, 1329–1331.
• Nelson, K. B. & Ellenberg, J. H. (1986). Antecedents of cerebral palsy: Multivariate analysis of risk. New England Journal of Medicine, 315, 81–86.
• Turkheimer, E., Haley, A., Waldron, M., D’Onofrio, B., & Gottesman, I. I. (2003). Socioeconomic status modifies heritability of IQ in young children. Psychological Science, 14(6), 623–628.
• Klebanoff, M. A. (2009). The Collaborative Perinatal Project: A 50-year retrospective. Paediatric and Perinatal Epidemiology, 23(1), 2–8.
• McGrath, J. J. et al. (2014). Advanced paternal age is associated with impaired neurocognitive outcomes during infancy and childhood. PLoS Medicine, 11(3), e1001038.