Misleading Claim on Teenage Marijuana Use

Federal Report Cited By Office Contradicts Claims That Young People Are Using Marijuana At Younger Ages

On Thursday the Office of National Drug Control Policy (ONDCP), headed by drug czar Gil Kerlikowske, issued a startling press release with the capitalized title “TEENS USING MARIJUANA AT YOUNGER AGES.” Citing the government's most recent National Survey on Drug Use and Health for 2009, the Office claimed that for marijuana, “the average age of initiation – first-time use of the drug − dropped from 17.8 in 2008 to 17.0 in 2009.”

After a closer look of the data cited by the ONDCP, the claim that teens today are currently using marijuana at younger ages is misleading. In fact, the same data shows that young people who recently tried marijuana are doing so at older ages.

The statistic used by the ONDCP comes from this sentence in the survey:

In 2009, the average age of marijuana initiates among persons aged 12 to 49 was 17.0 years, significantly lower than the average age of marijuana initiates in 2008 (17.8 years), but similar to that in 2002 (17.0 years).

The Office fails to mention in its press release that the .8 percentage drop in age among first time marijuana users was not based on a survey of teenagers, but came from an older demographic of those aged 12-49 years. There is no indication of when such behavior occurred, or that teens today are in fact trying marijuana at young ages.

When the demographic is narrowed down, to examine behavior in those who recently tried marijuana before turning 21, the age actually increases according to the survey. This is not mentioned by the ONDCP in its press release:

Among recent initiates aged 12 or older who initiated use prior to the age of 21, the mean age at first use was 16.3 years in 2009, which was significantly higher than the estimate (16.1 years) in 2008.

Considering that the national survey was released last month, the timing and purpose of the press release is interesting. Could this have to do with California's ballot question to legalize marijuana this November, an issue that the ONDCP has already worked to oppose? Or could this have anything to do with the Office's need to fund its National Youth Anti-Drug Media Campaign, which according to the Drug Policy Alliance, was recently defended by House of Representatives?

Whatever the reason, in this case that the federal data used in the press release is not in sync with the Office's claim on teenage marijuana use.

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Honkytonk said:

How are 17.8 compared to 17.0 and 16.3 compared to 16.1 SIGNIFICANTLY different ages? Aren't those marginally different ages at best?

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Mr Pengra said:

I don't mean to sound blunt about this; but why should anyone even care what age kids are finding out about it? they gotta learn about it sometime sooner or later.

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Tony Aroma said:

"Significant" is probably used here as a statistical term. It just means that a statistical analysis indicates that the difference is most likely real and not the result of variability in the data. In statistics, it's not meant to imply a large or meaningful difference. It just means that they are somewhere between 95% and 99.9% certain, depending on the level of significance, the change is not a fluke.

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Mr Pengra said:

I don't mean to sound blunt about this; but why should anyone even care what age kids are finding out about it? they gotta learn about it sometime sooner or later.

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