#13 - A six-month public health campaign sought to limit

[T.B.Justin]

Hey PS,

I have this as a causal argument which my be a stretch.

Health Campaign Lower Incidence

Answer Choice A:

Part of the health campaign (frequent hand washing) Lower incidence of some other illness


I missed this question my first pass through because of "food-borne illnesses" I thought that made this answer choice irrelevant since that has nothing to do with influenza, then I realized the way it best strengthens by showing that if this illness has a lower incidence was lower possibly due to frequent hand washing then its very likely the public is applying the advice of the public health campaign.

Also, I am just realizing how important understanding passage of time is on this test.

[tgold1]

Hoping someone can help me to understand why my thinking for B is incorrect. I can see why A strengthens but doesn't B also strengthen by eliminating alternate causes?

The argument purports to be a cause/effect case by identifying a correlation between the campaign and the incidence of influenza during those months. If the incidence of other illness also decreased during those months it could be that something else reduced the incidences of illnesses in general, ie. seasonal illness period ending. Thus, showing the cold incidence remained constant removes that possibility... Am I stretching it too far here?

[KelseyWoods]

Hi tgold1!

Yes, this is a causal argument in which the cause is the public heeding the health campaign and the effect is the lower incidence of influenza. As Rachel stated in an earlier post, answer choice (B) does not impact either the cause or the effect in this conclusion because we don't know what effect hand-washing has on the common cold. Also, the incidence of other illnesses decreasing during the same time period does not necessarily attack the conclusion that people heeded the campaign because these other illnesses could also be curbed by hand-washing, as we see in answer choice (A).

Hope this helps!

Best,
Kelsey

[Catallus]

You are correct that "fewer large public gatherings" could be related to "avoiding public places." However, you are also correct that there is enough of a conceptual gap between these ideas to make answer choice (C) less helpful than answer choice (A).

Answer choice (C) does give some evidence that could corroborate avoiding public places, but the connection is more tenuous. Just because large gatherings occurred less frequently we do not know whether people avoided public places in general.

Here you have to make a judgment call: which answer provides more direct evidence that the purported causes did indeed occur. There is little doubt that (A) is the better choice, even if you can make a case for (C).

Though I was ultimately more persuaded by (A), it was only because (A) said "markedly lower" rather than "fewer," suggesting a slightly stronger effect. I remain unconvinced that there is not a clear connection between the campaign's advice—stay home if you have flu symptoms—and the effect noted in (C)—fewer large public gatherings. The word "large" makes (C) especially attractive to me. Fewer "large" public gatherings than usual could be a direct effect of more people staying home when they have symptoms, i.e., heeding the campaign's advice. Public gatherings that normally would be "large" could become small or medium-sized, or canceled altogether, because people are avoiding public places due to flu symptoms.

I've seen it noted the lower incidence of public gatherings could be considered an alternative cause, but for the reasons noted above, it seems to me like it is (or could be) tied to the campaign rather than an unrelated factor.

Sure, there's speculation involved there; the phenomenon noted in (C) could be an effect of the campaign (via people staying home when sick), but isn't definitively so. However, it's no more speculative than (A). Lower rates of food-borne illnesses could likewise be an effect of the campaign (via more hand-washing), but this isn't definitive, either. Both answer choices give us a phenomenon that could either be explained by the campaign or, alternatively, could be explained by something else. They thus seem to have equal weakening force.

Any help in further distinguishing these answers would be appreciated!

[Catallus]

They thus seem to have equal weakening force.

Meant to say "strengthening" here—my bad.

[Adam Tyson]

The advice in the campaign had nothing to do with how many large public gatherings (sporting events, rallys, concerts, etc.) would occur, Catallus. It was only about avoiding public places (banks, grocery stores, busy sidewalks, etc.) when one shows symptoms. Fewer large public gatherings actually weakens the argument by suggesting an alternate cause for there being a lower incidence of influenza. Maybe nobody paid any attention at all to the campaign, and there were just fewer opportunities for influenza to spread?

Meanwhile, answer A strengthens the argument by showing another effect that one would expect if people were to heed the advice in the campaign and wash their hands more often.