The Protective Behavioral Strategies for Marijuana Scale: Further examination using item response theory.

Abstract

Given recent state legislation legalizing marijuana for recreational purposes and majority popular opinion favoring these laws, we developed the Protective Behavioral Strategies for Marijuana scale (PBSM) to identify strategies that may mitigate the harms related to marijuana use among those young people who choose to use the drug. In the current study, we expand on the initial exploratory study of the PBSM to further validate the measure with a large and geographically diverse sample (N = 2,117; 60% women, 30% non-White) of college students from 11 different universities across the United States. We sought to develop a psychometrically sound item bank for the PBSM and to create a short assessment form that minimizes respondent burden and time. Quantitative item analyses, including exploratory and confirmatory factor analyses with item response theory (IRT) and evaluation of differential item functioning (DIF), revealed an item bank of 36 items that was examined for unidimensionality and good content coverage, as well as a short form of 17 items that is free of bias in terms of gender (men versus women), race (White versus non-White), ethnicity (Hispanic versus non-Hispanic), and recreational marijuana use legal status (state recreational marijuana was legal for 25.5% of participants). We also provide a scoring table for easy transformation from sum scores to IRT scale scores. The PBSM item bank and short form associated strongly and negatively with past month marijuana use and consequences. The measure may be useful to researchers and clinicians conducting intervention and prevention programs with young adults.

The Relationship Between Risk Factors and Alcohol and Marijuana Use Outcomes Among Concurrent Users: A Comprehensive Examination of Protective Behavioral Strategies

“…Although Treloar et al (2015) dropped a manner of drinking item ("drink shots of liquor") from the original measure (Martens et al, 2005) for psychometric reasons, we found that this item can be maintained by modifying the item to be consistent with the remaining items ("avoid drinking shots of liquor"). Marijuana PBS use was assessed using the 17-item version (Pedersen et al, 2017) of the Protective Behavioral Strategies-Marijuana Scale (Pedersen et al, 2016).…”

Use of Protective Behavioral Strategies among Young Adult Veteran Marijuana Users

“…The PBSM was developed and validated in our prior work (Pedersen et al, 2016a; 2017a). We utilized the brief version of the scale (the PBSM-17), which contains 17 items from the larger 36 item bank that were determined with item response theory analyses to be free from bias regarding gender (male/female), race (White/non-White), ethnicity (Hispanic or Latino(a)/non-Hispanic or Latino(a), and state legalization status (i.e., whether respondents lived in states that had laws regarding legal recreational marijuana or not) in a large young adult college sample.…”

“…The scale displayed adequate internal reliability (α = 0.95). Scores on the PBSM were computed as a continuous value by summing responses and converting raw scores to T-scores as advised by Pedersen and colleagues (2017a).…”

“…Marijuana protective behavioral strategies are behaviors used before, during, after, or instead of using marijuana, such as taking periodic breaks if one feels like they are using marijuana too frequently, limiting the amount of marijuana one uses in one sitting, and avoiding using marijuana before work or school (Pedersen et al, 2017a; Pedersen, Hummer, Rinker, Traylor, & Neighbors, 2016a). Recent work has identified that use of these strategies by young adult college students are associated with fewer consequences and less frequent use (Bravo, Anthenien, Prince, Pearson, & the Marijuana Outcomes Study Team, 2017a; Bravo, Prince, Pearson, & the Marijuana Outcomes Study Team, 2017b; Pedersen et al, 2017a; 2016a) but no study to date has looked at use of marijuana protective strategies among veterans or among those with mental health symptoms. Use of these strategies may be particularly important for marijuana users who report symptoms of PTSD and depression as use of strategies may help protect them from further distressing consequences in their life as well as from exacerbation of symptoms.…”

Does the Combination Matter? Examining the Influence of Alcohol and Cannabis Product Combinations on Simultaneous Use and Consequences in Daily Life

“…These consistent findings underscore the importance of understanding manners of drinking beyond quantity and frequency, particularly considering that some protective behavioral strategies, such as stopping/limiting drinking, have demonstrated equivocal relations to alcohol‐related outcomes (see Pearson, 2013). Similar harm‐reduction strategies exist for manner of cannabis use, including avoiding mixing with alcohol and avoiding cannabis concentrates (Pedersen et al, 2017). Thus, some manners of SAM use may lead to more negative outcomes than others, and this may depend on the use of a specific product (e.g., liquor vs. beer) and/or the use of multiple products.…”