Optimizing Interventions News

Factorial Power Plan Macro

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Overview

The %FactorialPowerPlan macro can be used to do sample size and power calculations for planning either a factorial or fractional factorial experiment. The calculations can be done for either posttest-only or pretest-posttest designs. Participants can either be assumed to be independent, or nested within existing clusters as discussed in Dziak, Nahum-Shani, and Collins (2012).

The macro can be used for three separate purposes:

to calculate statistical power based on an available sample size and assumed effect size,
to calculate required sample size based on a desired statistical power and an assumed effect size, or
to calculate minimum detectable effect size based on available sample size and desired statistical power.

Recommended Citations

FactorialPowerPlan (Version 1.0) [Software]. (2013). University Park: The Methodology Center, Penn State. Retrieved from http://methodology.psu.edu

Dziak, J. J., Collins, L. M. & Wagner, A. T. (2013). FactorialPowerPlan users' guide (Version 1.0). University Park: The Methodology Center, Penn State. Retrieved from http://methodology.psu.edu

Come See Us at SPR!

Society for Prevention Research (SPR) Annual Meeting

San Francisco, CA, May 28-31, 2013

The Methodology Center will be active at the upcoming annual meeting of the Society for Prevention Research (SPR). At this year's conference, The Science of Prevention: Building a Comprehensive National Strategy for Well-Being, we will be presenting symposiums, a special interest group, paper talks, and multiple posters. Also look for us at the ECPN symposiums. We hope to see you there!

NIH Program Announcements Calling for SMART or MOST

Researchers planning to write a proposal that incorporates a sequential, multiple assignment, randomized trial (SMART) or that follows the multiphase optimization strategy (MOST) should review the NIH program announcements below. Each one calls for either SMART or MOST designs.

You may also want to review Linda Collins' advice for planning a grant proposal using MOST.

PA-13-077 Behavioral and Integrative Treatment Program (R01)

Agencies

National Institute on Drug Abuse (NIDA)
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
National Center for Complementary and Alternative Medicine (NCCAM)
Office of Behavioral and Social Science Research (OBSSR)

Purpose: "to encourage behavioral intervention development research..."

Designs specified: SMART

Open PA-13-077

PA-13-160 Alcohol Use Disorders: Treatment, Services, and Recovery Research (R01)

Agency

National Institute on Alcohol Abuse and Alcoholism (NIAAA)

Purpose: "to support research on behavioral and pharmacological treatment for alcohol use disorders..."

Designs specified: "adaptive clinical trial designs and statistical analyses that allow for adjustments to treatment based on the changing disease status of the patient." This is SMART.

Open PA-13-160

PA-13-165 Innovative Research Methods: Prevention and Management of Symptoms in Chronic Illness (R01)

Agencies:

National Institute of Nursing Research (NINR)
National Cancer Institute (NCI)

Purpose: "to update the randomized control trial design using novel research methods"

Designs specified: SMART and MOST

Open PA-13-165

Video: Optimizing Behavioral Interventions

April 5, 2013

As part of the “Medicine: Mind the Gap” NIH Seminar Series, Methodology Center Director Linda Collins recently gave a talk at the National Institutes of Health (NIH) in Washington D.C. She discussed the multiphase optimization strategy (MOST) and how it can be used to optimize interventions for smoking cessation, drug abuse prevention, treatment of obesity, promotion of physical activity, and other health-related behaviors. The seminar is part of the NIH lecture series that explores issues at the intersection of research, evidence and clinical practice—areas in which conventional wisdom may be contradicted by recent evidence. The goal of the series is to engage the NIH community in thought-provoking discussions about their role in helping to guide today’s research. This high-resolution video provides an excellent introduction to MOST.

Watch the video

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Download the slides

Upcoming Talk at NIH: Developing Behavioral Interventions

March 4, 2013

As part of the “Mind the Gap NIH Seminar Series,” Methodology Center Director Linda Collins will give a talk at the National Institutes of Health (NIH) in Washington, D.C., on March 26, 2013, about using the multiphase optimization strategy (MOST) to develop behavioral interventions for smoking cessation, drug abuse prevention, treatment of obesity, promotion of physical activity, and other health-related behaviors.

The seminar is part of the NIH's lecture series, titled "Medicine: Mind the Gap," which explores issues at the intersection of research, evidence and clinical practice—areas in which conventional wisdom may be contradicted by recent evidence. The goal of the series is to engage the NIH community in thought-provoking discussions about their role in helping to guide today’s research.

Pilot Project: Reducing Drinking Through Daily Physical Activity

February 22, 2013

Methodology Center Collaborative Research Funding has been awarded to David Conroy, Professor of Kinesiology and Human Development & Family Studies at Penn State. He will work with Nilam Ram and Methodology Center Investigators Runze Li, Stephanie Lanza, and Linda Collins to design an intervention that encourages physical activity among heavy drinkers in order to reduce alcohol consumption. Researchers believe that some forms of physical activity can reduce alcohol intake by enhancing enjoyment, improving mood, occupying time, and reducing reactions to stress. This project will address several unanswered questions about the relationship between physical activity and alcohol consumption and will use cutting-edge intervention-design methods to build an effective and efficient intervention.

New Grant to Optimize a Technology-Based Obesity Intervention

body changing from overweight to thin

November 7, 2012

Methodology Center Director Linda Collins is working on a new grant with Principal Investigator Bonnie Spring of the Northwestern University. In this project, the researchers will employ the multiphase optimization strategy (MOST) to develop a resource-efficient, Internet-and-phone based, weight-loss intervention.

Featured Article: Does it Really Matter How I Code My Data?

Effect Coding Versus Dummy Coding in Analysis of Data From Factorial Experiments September 18, 2012

Although it is commonly written in textbooks, researchers sometimes forget that how a categorical variable is coded determines the interpretation of its associated beta coefficient in regression analyses. In a new technical report, “Effect Coding Versus Dummy Coding in Analysis of Data From Factorial Experiments,” Methodology Center researchers Kari Kugler, Jessica Trail, John Dziak, and Linda Collins explain the differences between effect coding and dummy coding when the multiple regression approach is used to perform an ANOVA.

Faces of Penn State Recognizes Linda Collins

Linda Collins September 7, 2012

Faces of Penn State has selected Methodology Center Director Linda Collins for its new, university-wide campaign showcasing the personal accomplishments, public contributions, and pioneering spirit among members of the Penn State community. Linda is being recognized for her contributions to research in the social, behavioral, and health sciences. Congratulations, Linda!

Read her profile

Featured Article: Curbing Dangerous Drinking and Sex During Spring Break

July 9, 2012

Multiple studies have shown that going on a trip with friends during spring break is a risk factor for behavior including dangerous drinking and sex. In a new article in the Journal of Studies on Alcohol and Drugs, Methodology Center Investigator Megan Patrick and coauthor Christine Lee examined data from 261 undergraduates and found that students had greater odds of engaging in risky sex when they possessed greater pre-spring break intentions to have sex, and when they had a stronger sense that sex on spring break is common among their peers. The authors also found that being on a trip on a given day is associated with more drinking and sex, controlling for the fact that people who go on shorter trips or no trip at all.