IPHY 3700: Practice identifying ERs
Learning goals: Evaluate strengths and limitations of conflicting, competing, or incomplete
evidence, in order to reach an evidence-based conclusion about an unresolved scientific issue.
Argue the case for the best possible conclusion about an issue, when the evidence is imperfect.
Read the question sentence, position sentence, and paragraph below. Identify the ER sentence in
the paragraph. Then identify its CDE components (from ABCDE).
NQ: Does a vegetarian, vegan, or omnivore diet have a different effect on a woman’s risk of
osteoporosis? [an issue with conflicting evidence]
NP: Based on current research, it is most likely that there is no difference in the effect of these
diets on a woman’s risk of osteoporosis.
First ER paragraph:
First, measuring BMD is a more reliable way to detect osteoporosis risk than recording
incidence of fractures. All of the studies that found no difference in effect of the diets on
osteoporosis risk used BMD measurement, whereas half of those that found vegetarians or
vegans to have a higher risk used fracture rate as their determinant (Table 1). Fracture rate is a
less adequate measure of osteoporosis risk because fractures can occur regardless of bone
density, for instance from a car accident. In addition, a person with thin bones might just be
lucky enough to not fall and therefore not have any fractures. In an analysis of the effects of the
diets, such an individual would be listed in the low-risk column when in fact their low bone
mineral density might put them at high risk. BMD is more directly related to osteoporosis.
Table 1. Assessment Methods of Each Study
Vegan gives highest risk
Vegetarian gives highest risk
1: BMD
3: BMD
2: Fracture rate
4: Fracture rate
ERfind.docx
No difference
5: BMD
6: BMD and fracture rate
7: BMD
8: BMD
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