A social science researcher claims that later school start times improve student mental health. The researcher notes that after a district moved start times from 7:20 a.m. to 8:30 a.m., counseling visits for stress declined by 15% over the next semester. The researcher concludes that the schedule change caused the improvement and urges all districts to adopt later start times.
Which statement, if true, would most strengthen the researcher's argument?
- The district’s counseling office changed its appointment scheduling software during the semester.
- A comparable nearby district that did not change start times showed no similar decline in stress-related counseling visits. (correct answer)
- Some students reported disliking the later dismissal time because it interfered with after-school activities.
- During the same semester, the district also reduced homework requirements in several core classes.
Explanation: The researcher claims that later school start times improve student mental health based on a 15% decline in stress-related counseling visits after moving start times from 7:20 to 8:30 a.m. This argument establishes correlation and temporal sequence but needs additional evidence to support causation. The strongest support would be comparative evidence showing that districts without schedule changes didn't experience similar declines, ruling out alternative explanations like seasonal effects or broader mental health trends. Choice B provides exactly this control group evidence—if a comparable district with unchanged start times showed no similar decline, this would strongly suggest the schedule change caused the improvement. Choice D mentions reduced homework, which could be a confounding factor rather than support. Choice C about student preferences and Choice A about software changes don't strengthen the causal claim. Strong causal arguments require ruling out alternative explanations through controlled comparisons.