Literature on neighborhood effects on health largely employs
non-experimental study designs and does not typically test specific neighborhood
mediators that influence health. We address these gaps using the Moving to
Opportunity (MTO) housing voucher experiment. Research has documented both
beneficial and adverse effects on health in MTO, but mediating mechanisms have
not been tested explicitly. We tested mediation of MTO effects on youth asthma
(n = 2829). MTO randomized families living in
public housing to an experimental group receiving a voucher to subsidize rental
housing, or a control group receiving no voucher, and measured outcomes
4–7 years following randomization. MTO had a harmful main effect vs.
controls for self-reported asthma diagnosis (b = 0.24,
p = 0.06), past-year asthma attack
(b = 0.44, p = 0.02), and
past-year wheezing (b = 0.17, p
= 0.17). Using Inverse Odds Weighting mediation we tested mental health,
smoking, and four housing dimensions as potential mediators of the
MTO–asthma relationship. We found no significant mediation overall, but
mediation may be gender-specific. Gender-stratified models displayed
countervailing mediation effects among girls for asthma diagnosis by smoking
(p = 0.05) and adult-reported housing quality
(p = 0.06), which reduced total effects by
35% and 42% respectively. MTO treatment worsened boys’
mental health and mental health reduced treatment effects on asthma diagnosis by
27%. Future research should explore other potential mediators and
gender-specific mediators of MTO effects on asthma. Improving measurement of
housing conditions and other potential mediators may help elucidate the
“black box” of neighborhood effects.