Measurement and data analysis in research addressing health disparities in substance abuse.

This article describes concrete strategies for conducting substance abuse research with ethnic minorities. Two issues associated with valid analysis, measurement and data analysis, are included. Both empirical (e.g., confirmatory factor analysis, item response theory, and regression) and nonempirical (e.g., focus groups, expert panels, pilot studies, and translation equivalence) approaches to improve measures are described. A discussion of the use of norms and cutoff scores derived from a different ethnic group along with the effects of the ethnicity of the interviewer or coder on measurement is included. The section on data analysis describes why the use of race-comparison designs may lead to misleading conclusions. Alternatives to race-comparison analysis including within-group and between-group analyses are described. The shortcomings of combining ethnic groups for analyses are discussed. The article ends with a list of recommendations for research with ethnic minorities.