Which of These Statements About Biological Differences Between Blacks and Whites Are True?

Research published in the Proceedings of the National Academy of Sciences finds a correlation between medically trained individuals underprescribing pain medication to hypothetical black patients, and false beliefs those individuals hold about biological differences between black and white people. (Read the story here.)

In the study, 222 medical students and residents believed 12 percent of the statements below that are false. (Eleven are false; four are true.) Half of these students and residents believed at least one of the false statements.

Here are the statements the participants were given. The answer key is below.

1. On average, Blacks age more slowly than Whites.
2. Black people's nerve-endings are less sensitive than White people's nerve-endings.
3. Black people's blood coagulates more quickly -- because of that, Blacks have a lower rate of hemophilia than Whites.
4. Whites, on average, have larger brains than Blacks.
5. Whites are less susceptible to heart disease like hypertension than Blacks.
6. Blacks are less likely to contract spinal cord diseases like multiple sclerosis.
7. Whites have a better sense of hearing compared with Blacks.
8. Black people's skin has more collagen (i.e. it's thicker) than White people's skin.
9. Blacks, on average, have denser, stronger bones than Whites.
10. Blacks have a more sensitive sense of smell than Whites; they can differentiate odors and detect faint smells better than Whites.
11. Whites have more efficient respiratory systems than Blacks.
12. Black couples are significantly more fertile than White couples.
13. Whites are less likely to have a stroke than Blacks.
14. Blacks are better at detecting movement than Whites.
15. Blacks have stronger immune systems than Whites and are less likely to contract colds.

False beliefs: 1, 2, 3, 4, 7, 8, 10, 11, 12, 14, 15
True statements: 5, 6, 9, 13