Issue: September 2011

The Methodology Center
Penn State Lion Shrine


New Software Estimates the Effect of Latent Class Membership on a Distal Outcome

%LCA_Distal macroLatent class analysis divides research subjects into unobserved subgroups based on empirical data. The %LCA_Distal SAS macro uses a model-based approach to estimate the impact of belonging to a specific subgroup on an outcome at a later time. The macro works with PROC LCA, also developed by The Methodology Center. The macro accommodates binary, count, continuous, and categorical distal outcomes. All Methodology Center software is available as a free download.

Read more or download the macro.


New Video: How to Run a SAS Macro

How to Run a SAS MacroMany researchers use SAS to explore and process their data. The Methodology Center develops and distributes SAS procs and macros that make cutting-edge methods accessible to applied researchers. Although all SAS users are familiar with procedures (or procs), many users may not be familiar with macros. We created a four-minute video on how to run a macro. We use the new %LCA_Distal macro as an example, but the steps are generally applicable to any macro, whether or not it was created by The Methodology Center.

Watch the video


Featured Article: The Impact of Data Collection Frequency

Xianming Tan and Lisa DierkerRecent technological advances allow behavioral data to be collected with greater frequency than was possible in the past. The improved feasibility of frequent measurement has raised the question of how decisions regarding the spacing of observations may affect classification of behavioral trajectories. Xianming Tan, Lisa Dierker, and their collaborators explored this question using data on smoking patterns of first-year college students. They found that using snapshot data caused substantial misclassification of individual participants compared to the more frequently collected contiguous data, especially for those with the most variable behavior. Despite the increase in subject burden of contiguous measurement, in studies whose primary aim is to characterize substance use trajectories, more is better.

Read more.



Summer Institute Podcast

2011 Summer InstituteEarlier this month, The Methodology Center held our 16th annual Summer Institute. Center Director, Linda Collins, presented a two-day workshop on the Multiphase Optimization Strategy (MOST), a framework for optimizing and evaluating behavioral interventions. During the workshop, we sat down with some of the participants to discuss MOST, the Summer Institute, and applying new methods in their research. Arthur Blank, Mildred Moldonado-Molina, Kelvin Choi, and Linda Collins are interviewed.

Download the podcast.



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The Methodology Center
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State College, PA 16801

Phone: 814-865-3253
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