Impact of a Water Balloon

When an Impact Does Not Cause an Effect

The language of cause cause and effect is slippery. That’s what we’ve learned this week from the American Journal of Preventive Medicine. “The Impact of U.S. Free Trade Agreements on Calorie Availability and Obesity: A Natural Experiment in Canada” appeared last May in that journal. This week, the authors of that article explained that “impact” is a word that “cautiously” evokes the “language of association.”

In other words, by writing that free trade has an has an impact on obesity, they are in no way suggesting it is the cause of anything. At least that’s what they say. “We never use the word ’cause’ or any variant thereof.”

Testing Causal Assumptions in Obesity Research

If not for Jameson Voss, we never would have gained this nugget of wisdom. He wrote to the editors of AJPM to caution against “unwarranted speculation” about causes of obesity prevalence in that May publication. His letter suggested that the authors were making false assumptions about the relationship between food availability and obesity prevalence. Researchers should not assume such relationships are untestable, says Voss. More rigorous testing of free trade effects on obesity is feasible.

However, the authors of the original paper do not agree. It might be “ideal” to do more testing, they say, but they can’t see how it would be “realistic.” And from there, they jump into their explanation that the word impact does not invoke the idea of cause and effect. Uh huh.

NB: Oxford defines impact as “a marked effect or influence.”

Relative Frequency of 'Impact' in English Language BooksThe I-Word Has Become Irritating Jargon

Here at ConscienHealth, this absurd rationalization offers some validation. For some time, our editorial director has cautioned against overuse of the i-word. It seems we have an epidemic of it, as data from Google shows. Furthermore, she absolutely bans verb and adjective forms of this overused word. It’s irritating jargon. She’s right and vindication is sweet.

When does an impact not cause an effect? Apparently, that happens when one is writing about obesity and public health.

Click here for the original publication, here and here for the letters about it.

Impact of a Water Balloon, photograph © Derek Raugh / flickr

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January 26, 2019