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How to convince volunteers to care for trees

February 24, 2011 By Leave a Comment

The evidence shows that trees are an important part of our landscape – whether here in forested Ithaca, or in densely populated urban areas.

Studies have found that trees help improve focus, promote a sense of community, and deter crime. So it’s no surprise that major cities across the nation are launching initiatives to plant trees. New York City is undertaking one such project.  Called the MillionTreesNYC initiative, it aims to plant one million trees across all five city boroughs by 2017.

But urban forestry projects typically encounter a problem, explained Gretchen Ferenz, a senior extension associate at Cornell Cooperative Extension in New York City.

“Capital project funds will support planting and immediate care of trees for a couple of years, but costs for longer term care to ensure a young tree’s growth often are not included in municipal budgets,” she told the Cornell Chronicle for a story. “As a result, many urban trees do not survive into maturity.”

Ferenz’s office has joined forces with Cornell’s Department of Natural Resources to create the Urban Forestry Community Engagement Model, a program that provides workshops about the importance of trees to community members in two New York City neighborhoods. The goal is to enlist residents and organizations to become stewards of their community’s trees and, ultimately, to develop resources to help groups around the country do the same.

As part of the program, they’re collecting evidence to learn how to get more community members involved in caring for trees in their neighborhoods. They recently published a study that examines motivations and recruitment strategies for urban forestry volunteers.

Through a survey and focus groups, as well as a review of existing literature on the topic, the team found volunteer who plant and care for trees in their communities are motivated by a wide range of factors.  And most have a limited knowledge of the benefits of urban forests.

This type of work is an important first step in helping cities learn how to engage community members to help care for trees in their neighborhoods – and ultimately in making our world a bit greener.

(You can learn more about the Urban Forestry Community Engagement Model by clicking here.)

Filed Under: Cornell Cooperative Extension, Evidence-Based Living, policy Tagged With: , , , , , ,

Stroke or migraine? Serene Branson’s case makes people wonder

February 22, 2011 By 1 Comment

The video of reporter Serene Branson suddenly speaking incomprehensibly as she tried to report on the Grammy Awards brought out a fascinating – in in the digital age, typical – response. The first reaction on the part of many people was to think it was very funny. How often does one see a well-coiffed reporter saying what sounds like: “A very, very heavy birtation tonight, a very derri-derrison.”

But the public response quickly changed from laughter to deep concern. And then, the concern lightened a bit, as new information came in. Comments on these videos followed the public’s reaction. In response to one Youtube “remix” of her garbled speech, viewers wrote in this order:

“Hilarious!”

“Oh man she had a stroke…not funny.”

“She didn’t have a stroke, just a migraine.”

And in fact, the medical diagnosis turned out to be a “complex migraine,” and not a stroke.

All of this probably left many people wondering: How would I know if it’s a stroke or a complex migraine? This is a very important question, because stroke is a huge health problem in the United States: it’s the third leading cause of death and the primary cause of disability among adults. Medical treament of stroke is getting better and better, but all the experts agree that speedy treatment for stroke is extremely important.

A helpful review recently appeared in The Journal of Family Practice called “Is It Stroke, or Something Else?” Drs. Konrad Nau, Todd Corcco, Johanna Biola, and Hollyn Larrabee note that rapid response is crucial in cases of stroke, but it is complicated when people have conditions that mimic stroke.

One of these is complex migraine, which Serene Branson apparently suffered. Complex migraine can mimic stroke symptoms, including hemiparesis (weakness on one side of the body), vision loss, and aphasia (language problems). It’s the latter that was so obvious with reporter Branson. Usually a migraine comes on more slowly than a stroke and there is often a migraine “aura” that occurs prior to the episode. Age is also a factor: The average age for stroke is around 70, whereas complex migraines usually develop before age 40.

An easy-to-read article on the differences between stroke and complex migraine can be found here.

So what should we do? Fortunately, the answer is an easy one: All the experts say that if you have any of these symptoms (weakness on one side of the body, sudden trouble speaking, vision loss), seek medical attention immediately. This is one case where we can’t try to figure it out ourselves – get to your doctor or emergency room right away.

Filed Under: Evidence-Based Living, Health and Wellness, In The Media Tagged With: ,

New federal diet guidelines follow the evidence

February 17, 2011 By 2 Comments

Here at EBL, we’ve discussed how difficult it is to figure out what nutrition advice to follow, especially when there’s so much health and nutrition advice in the media that refers to anecdotes and simplistic inferences from single studies.

For those looking for real evidence about what to eat, there’s some good news.  The federal government has issued new dietary guidelines based on an extensive evidence-based review.

The U.S. Departments of Agriculture and Health and Human Services appointed 13 nationally-recognized experts in nutrition and health to review the scientific literature on how nutrition impacts health and disease prevention.

The experts worked with a new resource – USDA’s Nutrition Evidence Library, a clearinghouse of systematic reviews designed to inform federal nutrition policy. (You can read more about the process the panel used to create the new nutrition guidelines by clicking here.) The library employs post-graduate level researchers with experience in nutrition or public health to build its content.  The researchers analyze peer-reviewed articles to build bodies of evidence, develop conclusion statements and describe research recommendations.  It’s an EBL dream! 

So what do the new guidelines recommend? 

The entire report from the committee of experts is more than 400 pages long, with specific advice on everything from energy balances to food safety.  Government officials distilled this report into 112 pages of dietary guidelines, and 23 recommendations for the general population. Among them are:

  • Focus on consuming nutrient-dense foods and beverages.
  • Reduce daily sodium intake to less than 2,300 milligrams (about 1 teaspoon).
  • Limit the consumption of foods that contain refined grains, especially refined grain foods that contain solid fats, added sugars and sodium.
  • Eat a variety of vegetables, especially dark-green and red and orange vegetables, and beans and peas.
  • Consume at least half of all grains as whole grains. Increase whole-grain intake by replacing refined grains with whole grains.
  • Increase the amount and variety of seafood consumed by choosing seafood in place of some meat and poultry.

As you can imagine, the EBL team is thrilled that the government is using systematic reviews to make national diet recommendations.  They’re worth reading to see if you can improve your own diet.  Even small changes can make a big difference when you consider the evidence.

Filed Under: Evidence-Based Living, Health and Wellness, policy, The Learning Center Tagged With: , , , , , , , ,

New evidence on how the flu spreads

February 14, 2011 By Leave a Comment

We’re deep into flu season in the U.S. The federal Centers for Disease Control, which tracks the flu virus nationally, found a significant increase in flu-related hospitalizations and deaths in January.

I should admit to you that I was one of those patients.  I came down with a cough mid-January that quickly turned into body aches and fever.  Being pregnant, I went into the doctor for a check-up.  They immediately sent me to the hospital where I tested positive for the flu.  I was treated with IV fluids, fever-reducers and an antiviral medicine that has been shown to reduce the duration of the flu. Thankfully, I was much better within a week.  While I was sick, I did find myself wondering more than once, “Where did I pick this virus up?”  (My husband and son never got sick.)

So when I came across a new study in the Proceedings of the National Institutes of Science about how the flu spread, I was personally intrigued.

Researchers studied an outbreak of H1N1 flu virus at an elementary school in Pennsylvania in the spring 2009. They collected data in real time while the epidemic was going on, a unique method for studying the flu. In total, they collected information on 370 students from 295 households. Nearly 35 percent of the students and 15 percent of their family members came down with flu.

The interesting aspect of the study is that researchers collected data on exactly who got sick and when, plus information from seating charts, activities and social networks at the school.  They then used statistical methods to trace the spread of the disease from one child to the next.

Their findings were surprising:

  • Sitting next to a classmate with the flu did not significantly increase the risk of infection, but the social networks and the structure of classes certainly did.
  • Transmission was 25 times as intensive among classmates as between children in different grades. Boys were more likely to catch the flu from other boys, and girls from other girls. From May 7 to 9, the illness spread mostly among boys. From May 10 to 13, it spread mostly among girls.
  • Administrators closed the school from May 14 to 18, but there was no indication that this slowed transmission.  
  • Only 1 in 5 adults caught the illness from their own children.

The researchers did point out some limitations of the study. Survey data was reported by the main caregiver in each household and focused on symptoms only. And the study did not take into account how the flu spread outside of the school environment, at gatherings like play dates or sports practice.

But the study does provide a unique snapshot at how a virus can spread, revealing definite patterns of what the researchers call “back-and-forth waves of transmission” between the school, the community, and the households. It is one, detailed piece in the complex puzzle of understanding how disease spreads.

Filed Under: Evidence-Based Living, Health and Wellness Tagged With: , ,

Does diet soda cause strokes? Nope!

February 10, 2011 By 8 Comments

I am guessing that many families reading the paper at breakfast today had this happen: Somebody said to someone else: “See, I told you drinking diet soda was bad for you!”

And that is because of a study reported widely in the media regarding the relationship between consumption of diet soda and stroke. Strokes are very bad things, often devastating the person to whom they occur, so a finding about anything that might increase our risk for stroke is worthy of notice.

 At Evidence-Based Living, one of the most fun things we do is to track back from the media coverage to the actual research findings. In so doing, we hope to help people figure out the nature of the evidence and whether we should immediately change our behavior. This was an unusually big story, and so we ask: Believe it or not?

First, let me say that media coverage was a little more measured than usual. Some news outlets did use headlines like that from Fox News: “Diet Soda Drinkers at Increased Risk for Stroke” which make it sound like a firm finding (and probably led to some of the heated breakfast-table conversations). But many other outlets included the all-important “may” in the headline, and the articles themselves included qualifications about the study. 

So let’s take a look at this finding, using some of the key questions EBL recommends you always employ when you are trying to figure out whether a scientific finding should change the way you live. 

1. What kind of a study was this? Was it a good one?

 This is what scientists call an observational study. It was not a randomized, controlled experiment in which some people were asked to drink diet soda and others were not. It uses a longitudinal study called the Northern Manhattan study (or NOMAS). And yes, it is a very good study of its kind. It looks at stroke risk factors across white, black, and Hispanic populations living in the same community (northern Manhattan). It is a large and representative sample, followed up annually to determine if people suffered a stroke (verified by doctors on the research team). Many publications in top referred scientific journals have been published from the study (some of which are available for free on the website). 

2. Where did the information in the media come from? 

Here, in EBL’s opinion, is the first problem. The results were presented at a scientific conference this week (the American Stroke Association). This is not the same as being published in a referred scientific journal. In addition, we cannot follow an EBL cardinal rule: Go to the original article. The only information that is available on the study is from a press release issued by the association and subsequent interviews with the study’s lead author and other experts. So we need to wait until the results are published before we even think of changing our behavior in response to them. 

3. Are the results definitive?

No, no, and again no. There are some good reasons not to drink diet soda (including possible increased risk of diabetes and osteoporosis), but these findings do not “prove” that diet soda leads to strokes.  

Some reasons why this is a very tentative and preliminary finding include the following: 

  • All the data are self-report, so we are dependent on people remembering their diet soda consumption. 

  • It’s the first study to show this association. EBL readers know that we need multiple studies before we even begin to think about recommending behavior change.

  • It’s not all diet soda drinking: It looks like only people drinking diet soda every day show the association with stroke, suggesting that lower consumption may not increase risk. 

  • The study is not representative of the U. S. population. First of all, you had to be over 39 years old in 1990 to get in the study and the average age of the sample now is in the late 60s, so the results can’t be generalized to younger people. Further, the sample for this study included 63% women, 21 % whites, 24 % blacks and 53 % Hispanics. In the U.S as a whole, 51% of the population are women, 77% are white, 23% black, and 16% Hispanic. So it’s a very different group from what a random sample of Americans would get you.

  • We don’t know the reason for the association. The lead author, Hannah Gardener, is open about this: “It’s reasonable to have doubts, because we don’t have a clear mechanism. This needs to be viewed as a preliminary study,” By “clear mechanism,” she means that even if this relationship exists between diet soda and stroke, we don’t know why. 

There’s more we could say, but our main point is this: It doesn’t take very long for you to “deconstruct” what the actual evidence is behind a news story. With a basic understanding of how studies are done and access to the Web, you can often find out as much as you need to know. In this case, the media have reported the first highly tentative findings of an association between two things. Now other scientists need to test it again and again to see if it holds up, as well as finding out why the association exists.

 I go for sparkling water instead of diet soda because of other problems mentioned earlier with diet beverages.  But regarding stroke risk, the data just aren’t there yet. 

   

Filed Under: Evidence-Based Living, In The Media, The Learning Center Tagged With: , , ,

What we know about gay teenagers

February 9, 2011 By Leave a Comment

Over the past year, the news has been filled with stories of the suicide among gay teenagers who’ve suffered bullying from their peers.  The stories are tragic. And there’s no doubt that some gay teenagers suffer more emotional distress than straight ones. But what do we really know about their lives?  Is the discrimination overplayed in the news media?

Ritch Savin-Williams, professor of Human Development at the College of Human Ecology and director of Cornell’s Sex and Gender Lab, has written a book that covers these topics called The New Gay Teenager.

In the book, Savin-Williams makes the point that it is much easier to get grants to study clinical problems and treatment, meaning that gay teenagers without health or emotional problems have fallen under the radar of most academic studies.

“We hear only the negative aspects from research. We don’t hear about normal gay teens,” he told the New York Times for an article earlier this year.  “It’s hard to get studies published when researchers don’t find differences. A large number of studies found no group differences between gay and straight youth, but these have not been published.”

Hi main concern is that the media presents a negative picture to teenagers who are questioning their sexuality.

“I’m concerned about the message being given to gay youth by adults who say they are destined to be depressed, abuse drugs or perhaps commit suicide,” he said. “I believe the message may create more suicides, more depression and more substance abuse. I worry about suicide contagion. About 10 to 15 percent are fragile gay kids, and they’re susceptible to messages of gay-youth suicide.”

More recent studies have found that straight youths are just as much at risk of being bullied if they exhibit atypical behavior.

“Bullying is less about sexuality than about gender nonconformity,” Dr. Savin-Williams said. “There are straight youth who are gender-atypical and they suffer as much as gay kids. But whether there’s a direct link between bullying and suicide among gay teens has not been shown.”

Filed Under: Evidence-Based Living, In The Media, Youth Development

How do I know if a program works? A “CAREful” approach

February 6, 2011 By 1 Comment

I was recently giving a talk on intervention research and I was asked: “How do I tell whether the evidence for a particular program is good or not?” I often talk with practitioners in various fields who are struggling with exactly what “evidence-based” means. They will read “evidence” about a program that relies only on whether participants liked it, or they will see an article in the media that recommends a treatment based on a single study. What should you look for when you are deciding: Is the evidence on this program good or not?

I came across a very helpful way of thinking about this issue in the work of educational psychologist Joel R. Levin. He developed the acronym “CAREful research,” which sums up what needs to be done when drawing conclusions from intervention research.

In Levin’s “CAREful” scheme, he identifies four basic components of sound intervention studies.

Comparison – choosing the right comparison group for the test of the intervention. Usually, there needs to be a group that does not receive the program being studied, so one can see if the program works relative to a group that does not receive it. A program description should explain how the comparison was done and why it is appropriate.

Again and again – The intervention program needs to be replicated across multiple studies; one positive finding isn’t enough.

Relationship – There has to be a relationship between the intervention and the outcome. That is, the intervention has to affect the outcome variables. That may seem simple, but it’s important; the program has to have a positive effect on important outcomes, or why should you use it?

Eliminate – The other possible explanations for an effect have to be eliminated, usually through random assignment to experimental and control groups and sound statistical analysis.

 Levin and colleauges sum up the CAREful scheme:

“If an appropriate Comparison reveals Again and again evidence of a direct Relationship between an intervention and a speciried outcome, while Eliminating all other competing explanations for the outcome, then the research yields scientifically confincing evidence of the intervention’s effectiveness.”

To see a good example of an evidence-based approach to intervention that reflects this kind of CAREful research, take a look at the PROSPER program, which takes a similar approach to youth development progams.

So when you are looking at intervention programs, “Be CAREful”: Applying these four criteria for good research can help you decide what works and what doesn’t.

Filed Under: Evidence-Based Living, The Learning Center Tagged With: , , ,

Weird science reporting: My Saturdays with USA Weekend

February 5, 2011 By 3 Comments

On Saturday mornings, my wife and I take turns getting the paper and the morning coffee, and we relax with it for a half hour before starting the weekend routine. My spouse has become used to my reaction when I turn to the magazine that comes with our paper: USA Weekend. Or more accurately, she has become used to covering her ears. When I put my Evidence-Based Living hat on, I believe that USA Weekend’s science reporting could at least enter any “worst of the year” contest.

But then I realized: This may be a “teachable moment” for me and others! On the positive side, it’s nice that relatively heavy coverage is given in USA Weekend to scientific findings. Their health and lifestyle articles are filled with “a recent study shows…” And they make many recommendations regarding nutrition, much of it supposedly based on science. There is even a celebrity panel called “The Doctors” who purport to answer your health questions.

Ah, but the road to you-know-where is paved with good intentions. And what you get from USA Weekend is almost the opposite of good evidence-based advice: It’s a mish-mash of simplistic inferences from individual studies mixed in with folk wisdom and anecdote – and it’s nearly impossible for the lay reader to tell the difference. As such, it’s a great example of exactly the kind of “science journalism” you should avoid taking too seriously. Let me give you a few examples of where the scientific advice provided in USA Weekend should have the label “Let the Reader Beware.”

1. No access to the original research. I am willing to be corrected on this, but nowhere on the USA Weekend site could I find any citations to the original studies. Evidence-Based Living always recommends you go back to the original scientific articles before believing the media, but so little information is given in a typical USA Weekend story that I couldn’t even determine what research was being referred to. If you can’t find the article, how do you know if the finding is real or not?

2. Reliance on a single study (or two). Regular readers of Evidence-Based Living know one cardinal rule: Never believe a single study (or a couple studies). Very often, articles in USA Weekend state: “Swedish scientists have found…” “New Research Shows…” “Two studies found,” “According to research presented at the American Chemical Society.”

What do we really need? All together now, EBL-ers: Systematic reviews of all available research leading to evidence-based practice recommendations. We need to see a finding replicated over and over, using rigorous scientific methods. We want those findings peer-reviewed by other scientists. And we want to know that they work outside of a controlled study. A couple of studies never prove a point, so we should not base our health-related behavior on the findings of a single study (and that’s what almost all scientists tell you at the end of their articles).

Just to give one example, USA Weekend reports that snoring is related to metabolic syndrome. In the closest article to this assertion I could find, the scientists qualify the finding extensively, including that the study is limited by the measures it used, by a small subsample, and by the cross-sectional (one-time) nature of part of the study. Where’s that information, USA Weekend?

3. Quick and confusing generalizations. The Doctors in USA Weekend make the somewhat astonishing recommendation: “Stop counting the calories (if you’re a woman over 65)” and they go on to suggest that it may be better for you stay at your current weight, because “Older women who lose weight can double their risk of hip fracture.” Now try as I might, I couldn’t find the exact reference, although there is research suggesting that weight loss can affect bone density negatively. But this says nothing about the total picture. Should a morbidly obese, diabetic person not lose weight because of a potential increase in hip fracture? Probably not, because the other obesity-related health problems can trump the increase in hip fracture risk.

Here’s a study idea for you: I wonder how many women read that comforting advice and dropped their diet, even if they are very overweight and at no particular risk of hip fracture. That’s why simple generalizations about studies do more harm than good usually.

What’s the lesson here? These snippets of information won’t necessarily do you any good unless you know where they come from, how the study was done, and how it applies to you. Does it fit with other scientific research? We’re told in this week’s issue that we should “sprinkle on the cumin” because “In a scientific study from India, cumin was found to be just as effective as an anti-diabetes drug in controlling diabetes in lab rats.” Does that apply to you? Who knows?

So go to the source whenever you can, and take your Saturday paper’s science reporting with a grain of salt!

Filed Under: Evidence-Based Living, Health and Wellness, In The Media Tagged With: , , , ,

Another evidence-based diet tip: Keep a diary

February 3, 2011 By 4 Comments

Are you still working on that New Year’s resolution to lose weight?  If so, there is some newly published evidence that might give you the boost that you need.

A systematic review published last month in the Journal of the American Dietetic Association concluded that there is a “consistent and significant positive relationship between self-monitoring diet, physical activity or weight and successful outcomes related to weight management.”  (You remember how much we love systematic reviews, right?)

The article reviewed 22 studies that looked at self-monitoring during weight loss programs.  Fifteen of the studies focused on keeping a food journal, one looked at keeping an exercise journal, and six tracked subjects who recorded their weight at least once a week. 

Researchers found that both written and electronic journals helped with weight loss.  They also found that that people kept a weekly record of their weight lost more than those who weighed themselves less frequently. 

Despite the conclusive evidence, the review identified limitations in the methods of many of the studies included. In all but two studies, participants were predominantly white and women. And most of them used self-reporting instead of researchers collecting the data themselves.

Still, the evidence is pretty clear:  If you want to lose weight, keep a journal of your diet, weight and exercise.  Just this simple task can make all the difference.

Filed Under: Evidence-Based Living, Health and Wellness, The Learning Center Tagged With: , , , ,

Energy drinks and alcohol: A terrible combination

February 2, 2011 By 2 Comments

Drinking and college have gone hand in hand for a long time. The fight song of Cornell University (my employer) actually tells the story of an undergraduate who is expelled for drinking

Tell them just how I busted

Lapping up the high highball.

We’ll all have drinks at Theodore Zinck’s

When I get back next fall!

 One thing about drinking is that it is often self-limiting: People reach a point where they fall asleep or feel disinclined to drink anymore. But in our ever-innovative society, businesses keep coming up with new ways to alter one’s consciousness, and students tend to be the innovators. One of the most pernicious new developments turns out to be energy drinks.

A new article in the Journal of the American Medical Association is a call to arms against mixing energy drinks and alcohol. Drs. Amelia Arria and Mary Claire O’Brien, experts on adolescent health, demonstrate why this combination is so dangerous. They note that “energy drinks have become enmeshed in the subculture of partying on US college campuses because of the simultaneous consumption of energy drinks with alcoholic beverages.”

You may recall that a few years ago, the beverage industry decided that adding caffeine to alcoholic drinks would be a good idea. The Food and Drug Administration disagreed last November, ruling that caffeine is an unsafe additive to alcoholic beverages. Studies suggest that this warning has not reached the ears of many undergraduates, who create their own energy cocktails by mixing alcohol with energy drinks.

The authors point out that energy drinks themselves are probably not very good for you. In particular, they typically include much larger amounts of caffeine than is found in coffee or cola beverages. And coffee and cola are usually consumed slowly, rather than in a “shot” that concentrates the caffeine. Studies have found negative effects of such intense caffeine consumption, like raising blood pressure and disturbing sleep.

But the problems are much worse when you combine something that intoxicates you with something that makes you more energetic. The dangers include:

  • Drinking high volumes of alcohol per drinking session
  • Increases serious alcohol-related consequences like sexual assault and drunk driving
  • People who mix alcohol and energy drinks underestimate how drunk they really are, because the caffeine might reduce sleepiness but doesn’t change any other effects of alcohol, leading to “wide-awake drunkenness.”
  • Caffeine can prolong the drinking bout by keeping people awake, and may thereby lead to greater risk of alcohol poisoning.

We at Evidence-Based Living are not in the business of making moral judgments, and if undergraduates are like we were back in my day, they won’t listen anyway. But many students we know do take scientific evidence seriously. So take a look at the article (and the studies they cite). We bet you will decide that caffeine is for the morning after, not the night before.

Filed Under: Evidence-Based Living
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