Ever wonder why you may be groggy in the morning starting school ridiculously early in the morning. This may be because adolescents begin a a delayed sleep phase. Researchers convinced a school to meet 30 minutes later in the mornings than usual. Class attendance improved and there were less visits to the health center for 'fatigue-related complaints'. Students were surveyed for mood prior to the study and after the 30 minute change and after the 30 min change, fewer students reported feeling depressed or irritable.
Let's criticize this study. The problems with self-report are numerous, the largest one that House (yea from the tv show) would agree with is prevarication (=lying). If you were a student and your school started at 9 instead of 8.30 don't you think you'd circle whatever you needed to to ensure they kept the newly instated rule? Of course you would. There is also research showing that people are very bad at judging the amount of sleep they get, so if students report that they sleep 8 hours, well they could just be wrong.
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