Brevia

Explaining the Relation Between Birth Order and Intelligence

See allHide authors and affiliations

Science  22 Jun 2007:
Vol. 316, Issue 5832, pp. 1717
DOI: 10.1126/science.1141493
  • Fig. 1.

    Relation between birth order and IQ score. Mean IQ scores for male conscripts, first-, second-, and thirdborn in Norway to mothers with single births only and first birth from 1967 through 1976, according to birth order and number of elder siblings who died in infancy (age < 1 year). Scores are adjusted for parental education level, maternal age at birth, sibship size, birth weight, and year of conscription. Error bars show 95% confidence intervals (CIs). Reference: birth order one.

Additional Files


  • Explaining the Relation Between Birth Order and Intelligence
    Petter Kristensen, Tor Bjerkedal

    Supporting Online Material

    This supplement contains:
    Materials and Methods
    SOM Text
    Fig. S1
    References

    This file is in Adobe Acrobat PDF format.

Stay Connected to Science

Navigate This Article