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Saliva test for Alzheimer’s? Bare-bones report misses a host of concerns

Rating

1 Star

Categories

Alzheimer’s May Show Up in Saliva

Our Review Summary

Alzheimer'sThis nugget of a story, while nicely written and easy to read, puts too much emphasis on the promise of new findings and not enough on the actual data involved in the study. Research by the University of Alberta in Canada looked at the composition of saliva from three groups of people — Alzheimer’s patients, people with mild cognitive impairment, and those whose mental skills were normal for their age. An analysis of the saliva from these three distinct groups showed specific differences in certain compounds present. The story suggests that the findings could form the basis of “a relatively easy and non-invasive way to determine which people are at higher risk of developing more serious degenerative brain conditions.”

But the story offers few if any specifics about the size or design of the study, its limitations, or the actual results of the investigation. While a competing HealthDay story took pains to point out the tentative nature of the study, this Time piece gives readers a cursory and overly optimistic view of its potential.

 

Why This Matters

Alzheimer’s dementia is a debilitating and increasingly prevalent condition in our aging society. If the described simple, non-invasive screening test is truly effective (which will take much more testing to find out), it could have an enormous impact that is potentially positive if we develop better treatments for Alzheimer’s patients and can take action based on the results. There is also potential for negative impact resulting from false positive and false negative results, and from knowing about a frightening diagnosis without having the ability to do anything about it.

Criteria

Does the story adequately discuss the costs of the intervention?

Not Satisfactory

There is no mention in this short story about the potential costs of such a test, if it proved to be viable. Of course, it’s too early to say anything definitive about cost, and offering a specific number might mislead readers by implying that the test is anywhere near ready to be used. But we think the story could have offered some sense of the technology behind the test and whether it’s advanced/expensive or cheap/widely available. Other tests using saliva are in use today and could offer a general comparison point to suggest the costs of a new test.

Does the story adequately quantify the benefits of the treatment/test/product/procedure?

Not Satisfactory

While the story outlines the potential benefits of such a test in general terms, it does not quantify the results of the study or tell readers how accurate the test was found to be. We think any story about diagnostic testing or screening should discuss the sensitivity and specificity of the test — numbers which tell us about how well the test finds people who actually have the disease and rules out people who don’t have it.

Does the story adequately explain/quantify the harms of the intervention?

Not Satisfactory

Direct harms from a simple saliva test seem improbable at best, given its non-invasive nature.  But the competing HealthDay story pointed out that even a saliva test could produce false positives that could cause real anxiety in patients, something that clearly could harm them. There is also the potential for false negative results, which would falsely reassure patients about their status. Even an accurate positive finding could cause harm, since it would inform people about their risk of a future condition without giving them the ability to do much about it.

Does the story seem to grasp the quality of the evidence?

Not Satisfactory

This story focuses on the findings of a very early study using a small number of participants. But the shortness of this offering — four paragraphs — isn’t sufficient to convey the preliminary nature of the research. A competing HealthDay story offers a lengthy paragraph outlining all the factors that might explain differences in the saliva makeup of the three groups and thereby negate the test’s use for determining Alzheimer’s. That story also emphasizes the tentative nature of the work numerous times. In cases like this, where the research is preliminary and the reporting is cursory, it’s worth questioning whether doing a story at all is worth it.

Does the story commit disease-mongering?

Not Applicable

The story doesn’t engage in disease mongering, but there’s really not enough context about the disease or its impact to justify a Satisfactory rating. We’ll call it Not Applicable.

Does the story use independent sources and identify conflicts of interest?

Not Satisfactory

The story doesn’t offer independent sources and only paraphrases information from the graduate student/principal investigator.

Does the story compare the new approach with existing alternatives?

Not Satisfactory

This story focuses solely on research suggesting that a simple saliva test might one day gauge the risk of developing the disease. It doesn’t discuss how Alzheimer’s is currently diagnosed or what risk factors might increase one’s likelihood of developing the disease.

Does the story establish the availability of the treatment/test/product/procedure?

Satisfactory

We give credit here for this acknowledgment: “The results aren’t conclusive enough yet for doctors to start using them to distinguish people who are more likely to develop Alzheimer’s.” However, readers overall may get the impression that the test’s clinical usage is coming soon, when that’s not likely the case. We’d be much more comfortable if the story included more information accurately portraying the tentative nature of the findings, findings that might be actually caused by other factors not studied.

Does the story establish the true novelty of the approach?

Not Satisfactory

The research discussed here is novel in a general sense, but the story doesn’t establish this to a satisfactory degree. A number of previous studies have looked at saliva markers of Alzheimer’s, and there are probably dozens of other blood tests, scans, and other approaches currently in development to address the diagnosis of Alzheimer’s disease. The story does not allude to this research.

Does the story appear to rely solely or largely on a news release?

Not Applicable

We didn’t see evidence that the story relied on this news release about the presentation. However, since it contains such limited information, it’s hard to determine how it was produced. We’ll rule it Not Applicable.

Total Score: 1 of 8 Satisfactory

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