Correlation Olympics

I was going to do this earlier but had important things to do and needed to be sane for a while.
Last night I put on my hazmat suit and waded into the articles presented at the Sleep 2011 conference.

Update: here's my favorite:

Timing, Extent, and Incidence of Sleepiness during College Lectures

Introduction: College students are reported to have excessive daytime sleepiness (EDS) attributable to suboptimal duration, timing, or quality sleep. EDS is associated with poor academic performance and under­standing of the underlying causal pathways is needed. The present study investigates fluctuations in level of sleepiness among college students during lectures. Attending a lecture is a ubiquitous college student ex­perience that often involves sitting quietly in a comfortable setting with the lecture as the predominant source of stimulation. This circumstance likely unmasks sleepiness. The aim of this report is to describe the tim­ing of sleepiness changes across lectures as well as the extent and inci­dence of increased sleepiness.

Methods: Data were collected from students during lectures presented in 5 different classes taught by different instructors. Starting at the begin­ning of a > 50 min lecture, students were signaled at 10-min intervals to rate their level of sleepiness (using clickers) with the Stanford Sleepi­ness Scale (SSS). The Epworth Sleepiness Scale was used to create low, medium, and high Epworth-Sleepiness groups.

Results: Data from two classes were dropped because of lecture inter­ruptions (exam reviews, etc). ANOVA of data for 104 students revealed that SSS sleepiness was lowest at the beginning of the lecture and high­est 30 minutes into the lecture (p < .001). This same quadratic function was observed for all 3 classes and all 3 Epworth-Sleepiness groups (all ps < .05). At the 30-min time point, 40%, 33%, and 23% of the high, moderate, and low Epworth-Sleepiness groups were very sleepy.

Conclusion: Sleepiness may substantially impair ability to benefit from a lecture. This exploratory study suggests that sleepiness among college students is unmasked by lectures and consistently reaches a peak about 30 min into a lecture.