Separating a Stated Number from a Causal Claim
Amara is reviewing a practice passage for the reading section. The passage reads: 'In a 2021 trial, 48 college students were randomly assigned to chew mint gum or a placebo for 10 minutes before a 20-minute reaction-time test. The gum group's median response time was 312 ms; the placebo group's was 329 ms. The authors reported p = 0.04 but noted that participants who chewed gum also reported feeling more alert. The trial did not measure sleep duration the night before.' Amara must answer items that ask what is explicitly stated and what is only implied. She notices one answer choice says 'chewing gum causes faster reactions' and another says 'the gum group's median response time was 312 ms.' She has 90 seconds per item and cannot use outside knowledge. She wants a reliable way to separate stated facts from interpretations, especially when the passage includes statistics and a possible confound.
1. Which of these is explicitly stated in the passage: 'chewing gum causes faster reactions' or 'the gum group's median response time was 312 ms'? Explain how you would defend your choice to a skeptical test-taker.
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The explicitly stated choice is 'the gum group's median response time was 312 ms.' The passage gives that exact group label, measure, and number. The causal claim is not stated: the passage reports a difference between groups, but it does not say gum caused the difference.
To defend the choice, point to the verb. 'Was 312 ms' is a report of a measured result; 'causes' is a causal relationship that would require ruling out alternatives. The passage itself flags one alternative: gum chewers 'also reported feeling more alert.' It also says sleep was not measured. Those details do not disprove causation, but they mean causation is an interpretation, not an explicit statement. A p-value of 0.04 supports a statistical difference in this sample; it does not by itself establish cause.
2. An item asks whether 'alertness may have influenced the results' is explicit or inferred. What is the best answer, and what wording in the passage supports it?
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It is inferred, not explicit. The passage explicitly says participants who chewed gum 'also reported feeling more alert.' That is a stated association. The passage does not explicitly say alertness influenced reaction time.
The inference is reasonable because alertness is a plausible link between gum chewing and faster responses, and the word 'also' invites the reader to notice that the gum group differed in more than one way. But the wording 'may have' is the clue that the test is asking for a bridge the passage permits, not a sentence it states. A strong answer should quote the explicit detail and then label the extra step as inference.
3. A choice says 'sleep was not a factor.' Is that supported by the passage? Explain.
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No. The passage says the trial did not measure sleep duration the night before. That is an explicit statement about a missing measurement, not evidence that sleep had no effect.
This is a classic scope error: absence of measurement is not measurement of absence. If sleep was not recorded, the passage cannot establish that sleep was irrelevant. A careful reader should keep the explicit fact ('did not measure sleep') separate from the stronger conclusion ('sleep was not a factor'). The latter would require data the passage says were not collected.