Efficacy and Mechanisms of Technology-based Behavioral Interventions

Hazardous alcohol use among college students is a significant public health concern that has resulted in the development of numerous interventions. Although motivational interviewing components are effective at reducing problematic alcohol consumption among college students via reductions in descriptive norms (i.e., the perceived drinking by peers), the effects of single-session brief motivational interventions (BMIs) on alcohol use and consequences are relatively short-lived (i.e., 3 months). Guided by a harm-reduction perspective, researchers have become increasingly interested in how protective behavioral strategies (PBS) can impact alcohol consequences beyond the effects of reduced alcohol consumption. PBS have been found to be a robust predictor of alcohol-related problems controlling for consumption, and multiple intervention studies have found that PBS mediates intervention effects. Few studies, however, have examined the efficacy of PBS-related intervention components.

Specific Aim 1a: The researchers will augment and improve extant college alcohol interventions by developing and rigorously evaluating an added PBS component to an existing BMI with demonstrated efficacy to further reduce alcohol-related consequences beyond what is explained by reduced consumption.

An additional goal of this research is to deliver PBS in a way that capitalizes on newer technologies that allow for the repeated in vivo delivery of alcohol interventions. Given the widespread use of handheld devices among the college population, ecological momentary intervention (EMI) shows great promise in producing lasting behavior for a modest cost.

Specific Aim 1b: The researchers will develop a technology-based, college-drinking ecological momentary intervention (EMI; a newer, less explored methodology) that is disseminated using mobile, hand-held devices, which can be used in vivo with every drinking episode.

Characterizing Intervention Efficacy. The researchers intend to demonstrate that adding a PBS-focused component can increase efficacy beyond standard single-session BMIs while keeping costs minimal. Although the researchers predict that the PBS-based EMI will effect greater and more lasting decreases in alcohol consequences beyond standard intervention, it is important to verify that cheaper, single-session alternatives are not as effective (i.e., PBS-based BMI). Therefore, the researchers intend to implement a 2 (EMI, Ecological Momentary Assessment only [EMA]) by 3 (no single-session intervention control, standard BMI, BMI plus PBS component) factorial design. The researchers will characterize the efficacy of the BMI+PBS and EMI over traditional, single-session BMIs in several ways:

Specific Aim 2a: The researchers will examine whether the EMI methodology effects greater and more lasting behavior change as compared to the EMA assessment conditions.

To accomplish Specific Aim 2a, the researchers will examine the main effect of assessment (EMI vs. EMA) to demonstrate that the EMI conditions yield better longitudinal outcomes regardless of the single-session intervention.

Specific Aim 2b: The researchers will examine whether the PBS intervention component leads to reduced alcohol related consequences as compared to a standard BMI, even with a single-session intervention.

To accomplish Specific Aim 2b, the researchers will examine the main effect of the single-session intervention to demonstrate that a single-session BMI that has been enhanced by the PBS component will yield superior longitudinal effects relative to a BMI without the PBS component regardless of assessment style (EMA or EMI); the researchers further expect both BMI groups to be superior to the no-intervention control.

Specific Aim 2c: The researchers expect the EMI to moderate the single-session intervention, such that the PBS-BMI coupled with EMI will yield superior longitudinal outcomes on drinking consequences.

The researchers expect the PBS intervention component to be most efficacious when delivered in vivo during high-risk, alcohol use situations (i.e., EMI), where student motivation and perceived norms about drinking are most challenged. By using a 2X3 design, the researchers will be able to verify the synergistic interaction and characterize the effect size of the relative superiority of the PBS single-session component coupled with the PBS-based EMI.

Mechanisms of Behavior Change. Unlike the BMI, which relies upon motivation and descriptive norm changes, the researchers expect the PBS intervention component to have different mechanisms of behavior change. Specifically, the PBS component is an intervention that emphasizes skill use rather than motivation. Further, when coupled with EMI, which is a direct behavioral intervention, the PBS component will effect change by targeting specific behaviors as opposed to drinking motivation.

Specific Aim 3: To characterize the differential mechanisms of behavior change across the single-session and EMI interventions.

The researchers expect key differences in the mediating variables across interventions conditions. The researchers will examine PBS norms, PBS perceived effectiveness, and motivation to change PBS to ascertain how the researchers can best effect increases in PBS use in college populations.