The real world is a messy place to collect data and draw conclusions, and The Daily Iowan’s June 27 editorial, “Drinking stats encouraging, not proof of programs’ efficacy,” did a good job of pointing out some of the challenges in interpreting data from the spring administration of the National College Health Assessment. Those data indicate that University of Iowa students have reduced their high-risk drinking rate by 8 percent.

The DI editorial suggests that the way in which the data were collected means that the results might not generalize to the undergraduate students as a whole. Both the 2009 and 2011 data were collected from students enrolled in Health and Physical Activity Skills courses. As noted in the fact sheet referenced in our press release, these students are similar to undergraduate students at large in terms of major, year in school, sex, GPA, membership in the Honors Program, and other characteristics. This convenience sample, with its 98 percent response rate, is actually a good deal more representative than the typical random survey on our campus, because those surveys usually get very low response rates and those nonresponders are systematically different from the responders. So, the national-assessment results are a pretty good description of the drinking behaviors of undergraduate students.

Tom Rocklin is the University of Iowa vice president for Student Life.