Beyond income: Material resources among drug users in economically-disadvantaged New York City neighborhoods

Background: Little is known about material resources among drug users beyond income. Income measures can be insensitive to variation among the poor, do not account for variation in cost-of-living, and are subject to non-response bias and underreporting. Further, most do not include illegal income sources that may be relevant to drug-using populations. Methods: We explored the reliability and validity of an 18-item material resource scale and describe correlates of adequate resources among 1593 current, former and non-drug users recruited in New York City. Reliability was determined using coefficient α, ω _h, and factor analysis. Criterion validity was explored by comparing item and mean scores by income and income source using ANOVA; content validity analyses compared scores by drug use. Multiple linear regression was used to describe correlates of adequate resources. Results: The coefficient α and ω _h for the overall scale were 0.91 and 0.68, respectively, suggesting reliability was at least adequate. Legal income >$5000 (vs. ≤$5000) and formal (vs. informal) income sources were associated with more resources, supporting criterion validity. We observed decreasing resources with increasing drug use severity, supporting construct validity. Three factors were identified: basic needs, economic resources and services. Many did not have their basic needs met and few had adequate economic resources. Correlates of adequate material resources included race/ethnicity, income, income source, and homelessness. Conclusions: The 18-item material resource scale demonstrated reliability and validity among drug users. These data provide a different view of poverty, one that details specific challenges faced by low-income communities.