Research of Note for February 2004

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Drug use is down, soft drink consumption is up, and Child Protective Services agencies don’t reach most abused kids. Here is the research behind the recent headlines.

Drug Use Down – What Does it Mean?

Monitoring the Future Study 2003
By Lloyd Johnston, Patrick O’Malley, Jerald Bachman and
John Schulenberg
Dec. 19, 2003
News release at; 44-page summary at or contact Johnston at University of Michigan, (734) 763-5043; data tables at

When a new release about a government-sponsored study credits the president of the United States for a decline in teen substance abuse, it makes me wonder if politics is getting in the way of science. If you read that “the 2003 Monitoring the Future Study confirms that President Bush’s goal to reduce drug use [by 10 percent in two years] has been exceeded,” you might wonder what to think. Let’s look at the numbers.

The study indicates that “current use (past 30 days) of any illicit drug between 2001 and 2003 among students declined 11 percent.” That sounds impressive. It doesn’t sound nearly as impressive, though, when you keep reading and learn that the decline in use is from 19 percent of the youth surveyed to 17 percent. Drug use in the past year also declined 11 percent (from 32 to 28 percent of youth surveyed), while “lifetime use” (having ever used drugs) declined 9 percent (from 41 to 37 percent).

Lifetime use of LSD “plummeted” by 43 percent – from 7 percent to 4 percent. (Research Watch has rounded all percentages to the nearest whole number.)

The Monitoring the Future study is a solid survey of more than 48,000 youths in the 8th, 10th and 12th grades at 392 public and private schools. It is a nationally representative sample that has been conducted for almost 30 years, and there is every reason to believe the survey analysis showing that drug use is decreasing.

However, an 11 percent decrease sounds much more impressive than a decrease from 19 to 17 percent. That’s the difference between stating the decline in the actual numbers (2 percentage points) and the decline as a percentage of the original statistic (the 11 percent). Both are correct, which brings to mind Mark Twain’s adage, “There are three kinds of lies: lies, damned lies and statistics.”

Making small changes seem larger is a common strategy for pharmaceutical companies: For example, “Wonder drug reduces risk of disease by 50 percent!” might mean the decrease is from 1 percent to one-half of 1 percent. Journalists like the more impressive numbers because they sound more newsworthy. For politicians, using the larger number makes good news sound even better.

In this case, the decreases in drug use were statistically significant, because the survey is huge. If the sample size had been 100 kids, these differences would not have been statistically significant, because such small changes could have occurred by chance in a smaller sample. Larger samples give us more confidence that the change is real – that is, it’s not a statistical fluke – but a statistically significant change is not necessarily a large change.

The press release from the Department of Health and Human Services touting the study found a ready explanation for the decline in drug use, saying, “This survey shows that when we push back against the drug problem, it gets smaller. Fewer teens are using drugs because of the deliberate and serious messages they have received about the dangers of drugs from their parents, leaders, and prevention efforts like our National Youth Anti-Drug Media Campaign.”

Let’s look at some of the details in the declines.

Use of marijuana, the most commonly used illicit drug among youth, declined significantly, with current and past year use reduced by 11 percent (from 17 to 15 percent and from 28 to 25 percent, respectively).

The government press release says that “the National Youth Anti-Drug Media Campaign, a comprehensive federal effort to provide drug prevention messages to America’s children, was reworked in 2002 to produce harder-hitting ads that have focused on the harms of marijuana. … Students say the ads they have seen make them less likely to use drugs in the future.” These kinds of statements by youths don’t necessarily mean much; the youths may say what they think researchers want to hear, and what youths say they will do and what they eventually do are often not the same.

What is really going on here? One possibility is that the use of some kinds of drugs declined while others increased. However, use of most kinds of drugs declined, as did lifetime and current use of cigarettes and lifetime use of alcohol. This indicates that teens are not trading one intoxicating substance for another.

It is also possible that teens are being less honest about their drug use because the media campaigns make drug use less socially acceptable. There have also been declines in recent years in abuse of prescription drugs, such as Ritalin and tranquilizers. This suggests that there could be a reduction in all kinds of drug use that has nothing to do with reductions in illegal drugs.

It is not possible to say whether the declines are due to specific programs or changes in attitudes, changes in reporting or other factors. Lloyd Johnston, the report’s principal investigator and a professor at the University of Michigan, says it is “quite possible” that the media campaign “has had its intended effect.” However, the report points out that marijuana use has been declining since its peak in 1996 – well before the new media campaign began in 2002.

The report is not finished, but the University of Michigan press release is extensive, and the data are presented in tables on the Monitoring the Future website.

Reading, Writing and Soft Drinks

Soft Drinks in Schools
American Academy of Pediatrics Policy Statement
Pediatrics, Vol. 113, January 2004, pgs. 152-154
Available free at, or contact American Academy of Pediatrics,
601 13th St. NW, Suite 400 North, Washington, DC 20005;
(202) 347-8600

The sale of soft drinks from vending machines in schools has been a controversial topic for years, as more schools have come to rely on the income from these machines for activities such as field trips and sports. Although less controversial, soft drinks are also available at or near recreation centers, after-school and summer youth programs, schools where athletic events are held, treatment centers and other places where youth spend their time.

In January 2004, the American Academy of Pediatrics published a policy statement on soft drinks in schools, which includes a summary of research that is relevant to all youth workers.

The pediatricians point out that there are three major health reasons for concern about soft drinks: impact on obesity, calcium deficiency because youth who drink soft drinks will drink less milk, and tooth decay and possible erosion of tooth enamel.

The research summary points out that soft drink consumption has tripled over the past 20 years, and that between 56 and 85 percent of school-age children drink at least one soft drink every day. Drinking an average of one more 12-ounce soft drink per day translates into a 60 percent increase in the risk of obesity.

Children and youth drink less milk as they drink more soft drinks, a transition that typically occurs between third and eighth grades. In addition to calcium, milk contains other important nutrients that are important for kids’ health. The decline in milk consumption can be harmful to kids, regardless of whether they are substituting bottled water, diet drinks, juices or regular colas. Unless the soft drinks contain calcium (as some juices and smoothies do), this threatens the development of bone mass, 40 percent of which occurs in adolescence. If bone mass isn’t fully developed during adolescence, it can’t develop later.

The policy statement points out that some superintendents, school board members and principals claim that selling soft drinks in schools is good for schools and taxpayers, but the decisions tend to be made by business offices, without input from health care professionals. The health care professionals say these decisions need input from others, not just those concerned with finances.
The policy statement is focused on pediatricians but is equally relevant to most youth workers. Its recommendations:

Work to eliminate sweetened drinks in schools.

Advocate the creation of school nutrition advisory councils of parents, community and school officials, food service representatives, physicians, school nurses, dieticians, dentists and other health care professionals.

School districts should invite public discussion before making decisions about vending machine contracts.

Make efforts to reduce the use of soft drinks in schools that already have soft drink contracts by, for example, not selling them in competition with or as part of a school lunch program; turning them off during lunch hours; not providing financial bonuses to schools based on the amount of soft drinks sold; or installing vending machines that sell real fruit and vegetable juices, water, low-fat milk and drinks that are sugar-free or low in sugar.

The statement provides excellent research resources on the topic, including 34 references, mostly from medical and journal articles on topics such as the link between colas and bone fractures, the nutritional consequences of diet and regular soft drink consumption, and cola wars in schools.

Child Protective Services Miss Most Abused Kids

Reported Contact With Child Protection Services Among Those Reporting Child Physical and Sexual Abuse
By Harriet MacMillan, Ellen Jamieson and Christine Walsh
Child Abuse & Neglect, Vol. 27, December 2003, pgs. 1397-1408
Available from MacMillan, Canadian Centre for Studies of Children at Risk, McMaster University, Patterson Building, Chedoke Division, Box 2000, Hamilton, Ontario, Canada L8N 3Z5

Child Protective Services (CPS) agencies are overloaded with cases of child abuse and neglect, but this new study supports the conclusion everyone fears: Those cases are barely the tip of the iceberg.

The study was based on interviews with a random sample of almost 10,000 residents over the age of 15 in Ontario, Canada. They were asked a wide range of health questions, including questions about physical or sexual abuse. Twenty-nine percent reported some kind of abuse when they were growing up, but only 5 percent of those who reported a history of physical abuse as children had contact with CPS, along with only 9 percent of those with a history of sexual abuse. There was no difference among those with severe sexual abuse and those with abuse that was not rated as severe.

Those who had contact with CPS tended to be younger when interviewed (not necessarily when abused) and to be female. The younger ages might indicate that the CPS agencies have done better in recent years at contacting abused children, or that the interview subjects may be more likely to remember such contact. Sexually abused children were more likely to have had contact with CPS if their parents worked in lower socioeconomic jobs.

Contact with CPS was evaluated by the response to the question: “Before age 16, did you ever see or talk to anyone from the Children’s Aid Society about difficulties at home?” Although only 3 percent of all the respondents said they had any contact with CPS, not all of that 3 percent reported being abused when they were growing up.

The large number of men and women who say they were abused growing up is worrisome, and it is unclear whether the results would vary greatly if the study was conducted in the United States. Even so, this study has clear implications for youth workers in Canada, the United States and elsewhere, because it indicates that most abused youth do not come to the attention of protective services.

Diana Zuckerman, Ph.D., is president of the National Center for Policy Research for Women and Families. Contact: Information about many Research Watch columns is available at