The Moving to Opportunity (MTO) experiment manipulated neighborhood context by randomly assigning housing vouchers to volunteers living in public housing to use to move to lower poverty neighborhoods in five US cities. This random assignment overcomes confounding limitations that challenge other neighborhood studies. However, differences in MTO’s effects across the five cities have been largely ignored. Such differences could be due to population composition (e.g., differences in the racial/ethnic distribution) and/or to context (e.g., differences in the economy).
Using a nonparametric omnibus test and a multiply robust, semiparametric estimator for transportability, we assessed the extent to which differences in individual-level compositional characteristics that may act as effect modifiers can account for differences in MTO’s effects across sites. We examined MTO’s effects on marijuana use, behavioral problems, major depressive disorder, and generalized anxiety disorder among black and Latino adolescent males, where housing voucher receipt was harmful for health in some sites but beneficial in others.
Comparing point estimates, differences in composition partially explained site differences in MTO effects on marijuana use and behavioral problems but did not explain site differences for major depressive disorder or generalized anxiety disorder.
Our findings provide quantitative, rigorous evidence for the importance of context or unmeasured individual-level compositional variables in modifying MTO’s effects.
Conflicts of interest: None
Sources of financial support: This work was supported in part by the National Institute on Drug Abuse (K99DA042127-01; PI: Rudolph). TLO, MMG, and NMS were supported by R01 MD006064.
Data and analysis code: Researchers may apply for data access through ICPSR: http://www.icpsr.umich.edu/icpsrweb/ICPSR/studies/31661. Computing code required to replicate the results will be made available on the first author’s github page: https://github.com/cherrygarcia/MTO-site-transportability-paper-code/blob/master/submissioncode1.R.
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