PhenX Toolkit Provides Standard Measures for Research

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NIDA researchers working with human subjects now have a new resource at their fingertips: the PhenX Toolkit’s new Substance Abuse and Addiction (SAA) collection. The Toolkit—a collaboration between NIDA, RTI International, the National Human Genome Research Institute, and the Office of Behavioral and Social Sciences Research—is designed to provide standardized measures, vetted and approved by the field, to help researchers compare and combine data from multiple studies.

Recently, NIDA teamed up with RTI to identify specific sets of SAA measures for NIDA investigators. This yielded first- and second-tier core measures—applicable to all NIDA studies involving human subjects—and six specialty sets of measures for researchers working in specific areas, such as psychosocial risk and neurocognition. The first-tier core includes essential, low-burden measures that all NIDA human-subject studies should use, such as current use status for alcohol, tobacco, and other addictive substances; age of first use; and 30-day quantity and frequency. The second-tier core includes important but more time-consuming measures, such as family history of substance abuse, social networks, and socioeconomic status.

With these new measures (, NIDA researchers are now able to more readily compare and combine their data with those from other studies, increasing statistical power and advancing scientific discovery through integrative data analyses. The use of standardized data across studies also helps researchers recognize previously unsuspected relationships and generate new hypotheses.

Currently, the Toolkit has more than 330 measures, all of which are well-established and easy to use, including the more than 40 measures of the SAA collection. The Toolkit’s Web site provides a brief description of each measure, the rationale for its inclusion, the standard protocols for collecting the data, and related references. A tutorial on the Web site demonstrates the use of the Toolkit to design a genetic epidemiology study of cardiovascular disease.

Overall, the PhenX Toolkit with the new SAA measures will make it easier for drug abuse researchers to include a uniform set of core measures in their study design, collect common data, and contribute to the addiction sciences. NIDA urges all of its researchers involved in human-subject studies to utilize this new resource; through investigator participation, NIDA will be able to leverage individual studies for a collective outcome, helping to create a more thorough understanding of addiction and how it can be stopped.

Accompanying the PhenX logo is a simplified illustration of a strand of DNA and a photograph of a baby holding the stethoscope of a young female doctor.