177009 Reliability and validity of the Spanish RBA: Translation issues, protocol drift, and drug distribution patterns

Monday, October 27, 2008

Michele M. Wood, PhD , Department of Health Science, California State University, Fullerton, Fullerton, CA
Dennis G. Fisher, PhD , Center for Behavioral Research and Services, California State University, Long Beach, Long Beach, CA
Alexander Rainof, PhD , Department of Romance, German, Russisan Languages & Literatures, California State University, Long Beach, Long Beach, CA
Judith M. Siegel, PhD, MSHyg , School of Public Health, UCLA, Los Angeles, CA
BACKGROUND: The NIDA RBA English interview was found to be reliable and valid; however, the Spanish version had not been tested.

METHOD: Participants were 22,755 English-speaking and 1,946 Spanish-speaking active drug users who completed the RBA drug-use items. Internal consistency of self-reported items was assessed to evaluate reliability. To evaluate validity, self-reported 48-hour use was compared to urine test results.

RESULTS: For both English and Spanish RBAs, internal consistency indicated almost perfect reliability for crack (kappa=.997, .998), cocaine (kappa=.968, .990), and heroin (kappa=.995, .992) use. Self-reported 48-hour use demonstrated substantial validity for the English RBA, with 88.5% agreement (kappa=.617) for cocaine, and 91.4% agreement (kappa= .808) for opiates. For the Spanish RBA, validity of self-reported use was only slight for cocaine, but substantial for opiates, with 65.5% and 85.7% agreement, respectively (kappa=.189, .676).

DISCUSSION: The Spanish RBA was found to be as reliable as the English RBA; however, the Spanish instrument was insufficiently valid for self-reported cocaine use, possibly contributing to null findings. This study highlights the importance of testing translated versions of instruments with known psychometric properties, examining multi-site data by site, establishing procedures to minimize “protocol drift”, and also the influence of potential geographic differences in drug distribution and the effect of rapidly changing, region-specific drug terms on drug use self-report. Funding should be made available to adequately test instruments in all languages into which they have been translated. The psychometric properties of translated instruments should be documented and/or published prior to their broader use.

Learning Objectives:
1. The audience will be able to describe the internal consistency reliability of English and Spanish measures assessing crack, cocaine, and heroin use. 2. The audience will be able to describe the validity of self-reports of cocaine and heroin use. 3. The audience will be able to discuss the importance of assessing the reliability and validity of translated instruments measuring drug use in the context of HIV and STD risk.

Keywords: Evaluation, Out-of-Treatment Drug Users

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I conceived and carried out the work.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.