Recent Poll on Dem Race Needs More Upfront Disclosure

By Lanny Davis – 9/29/15

This weekend’s NBC-Wall Street Journal poll has been widely reported all over Sunday’s news media and on the Internet: Hillary Clinton now leads Sen. Bernie Sanders (I-Vt.) by only 42 percent to 35 percent in the race for the Democratic nomination.

At the very end of the press release, it is revealed that the poll is based on 256 Democratic primary voters nationwide, which is a margin of error of plus/minus 6 percentage points.

Is that a responsible polling sample, with such a large margin of error?

In fact, the margin of error of plus/minus 6 percentage points means the results could be either that Clinton leads by 48 percent to 29 percent (plus 19 percentage points) or that Sanders leads 41 percent to 36 percent (plus 5 percentage points). Statistically, either result could be true, according to the poll’s own data. That is a fact.

Shouldn’t the NBC-Wall Street Journal poll have disclosed that fact more prominently in the press release and warned against inaccurate headlines that ignore the small sample size and large margin of error?

Shouldn’t other journalists writing about this poll disclose that fact, that the poll shows that Clinton could lead by 19 percentage points or that Sanders could lead by 5 percentage points — and either result is equally statistically possible?

Isn’t that type of factual disclosure obligatory?

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Mr. Davis is a weekly columnist for The Hill newspaper, writing under the name, “Purple Nation. “This column appears first and weekly in The Hill and the Hill.com.

Davis served as special counsel to former President Clinton and is principal in the Washington, D.C., law firm of Lanny J. Davis & Associates, and is executive vice president of the strategic communications firm LEVICK. He is the author of a recently published book, Crisis Tales: Five Rules for Coping with Crises in Business, Politics, and Life.

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