A new study finds that girls and boys have very different psychological reactions when families move out of high-poverty neighborhoods.

Previous studies have found high rates of emotional problems in youth living in high-poverty neighborhoods, even after controlling for factors that might influence the psychological development of each individual.

But these have mostly been observational studies, which are prone to selection bias and what researchers call “reverse causality.”

An example of reverse causality in this context would be if a study claimed that a poor neighborhood caused families living there to develop emotional problems, when really the families with emotional problems end up living in poorer neighborhoods.

To assess what impact quality of neighborhood really has on emotional well-being, the US Department of Housing and Urban Development enacted a housing mobility experiment from 1994 to 1998 called “the Moving to Opportunity for Fair Housing Demonstration.”

This experiment selected random families from a group of 4,604 volunteer low-income families to receive vouchers to move to lower-poverty neighborhoods.

A second group received geographically unrestricted vouchers, and a third group – who were used as a control group – received no vouchers.

The researchers behind the new study, published in JAMA, followed up with the families 4 to 7 years after randomization. They found that the intervention prompted families to increase social ties with more affluent people and move to better neighborhoods that had lower poverty and crime rates.

The researchers interviewed 2,872 adolescents as part of their investigation. The adolescents had been between 0 and 8 years at the beginning of the study, and they were between 13 and 19 at the time of the follow-up.

Significant reductions in psychological distress and depression were recorded among adolescent girls in the intervention groups, compared with girls in the control group. But increased behavior problems were found in boys in the intervention groups.

The study records the following differences in incidence of psychological disorders between the boys in the low-poverty intervention group and boys in the control group:

  • Major depression: 7.1% of boys in the low-poverty intervention group and 3.5% of boys in the control group
  • Post-traumatic stress disorder (PTSD): 6.2% intervention and 1.9% control
  • Conduct disorder: 6.4% intervention and 2.1% control.

In the geographically unrestricted voucher group, 4.9% of boys had PTSD, compared with just 1.9% in the control group.

But girls in this voucher group fared much better, with 6.5% having major depression and 0.3% having conduct disorder, compared with 10.9% and 2.9% of girls in the control group.

Why did the girls in the experiment thrive in their new surroundings while the boys struggled?

The authors suggest the differences “were due to girls profiting more than boys from moving to better neighborhoods because of sex differences in both neighborhood experiences and in the social skills needed to capitalize on the new opportunities presented by their improved neighborhoods.”

The authors say that it is difficult to see from their results what the implications for policy should be, “because the findings suggest that the interventions might have had harmful effects on boys but protective effects on girls.”

They add:

Future governmental decisions regarding widespread implementation of changes in public housing policy will have to grapple with this complexity based on the realization that no policy decision will have benign effects on both boys and girls. Better understanding of interactions among individual, family, and neighborhood risk factors is needed to guide future public housing policy changes in light of these sex differences.”