To examine occupational heritability in medicine and changes in heritability over time, with Swedish population wide administrative data that allowed mapping family trees of physicians spanning up to three generations.
Retrospective observational study.
Individual level administrative registry data from Sweden.
Physicians born in 1950-90 and living in Sweden at some time during 2001-16 (n=47 400).
Main outcome measures
The proportion of individuals with a completed medical degree with at least one parent who also trained in medicine, and the change in this proportion across birth cohorts. Additional analyses were conducted among other relatives (grandparents, aunts and uncles, and siblings) and for individuals with a law degree.
For 27,788 physicians, where the educational background for both parents was known, 14% had a parent who was also a physician and 2% had two parents who were physicians. The proportion of physicians with at least one physician parent increased significantly over time, from 6% for physicians born in 1950-59 to 20% for physicians born in 1980-90 (P<0.001). The same pattern of increasing occupational heritability was not seen for individuals with law degrees.
In recent cohorts of physicians in Sweden, one in five had a parent who was also a physician, more than triple the proportion seen for physicians born three decades earlier. A similar pattern was not seen in lawyers, suggesting that increasing occupational heritability in medicine does not reflect intergenerational persistence of high paying degrees alone. Rather, for physicians in Sweden, medicine might increasingly run in families.