Medicine by the numbers: Cornell professor on how we make health care decisions

These days, a routine trip to the doctor’s office can easily morph into a complicated calculation of risks and benefits. With the advent of pharmaceutical advertising and the plethora of medical information on the Internet, patients have more choices and responsibility to make decisions than ever before.

Enter Cornell professor Valerie Reyna, a faculty member in human development and expert in judgment and decision-making.

Her ground-breaking research has shown that medical information is difficult to understand for people of all education levels. In laboratory studies and analyses of real-world data, Reyna has found that adults tends to make all decisions – including medical decisions – based on the overall meaning or gist of situation, instead of using statistics and details. So there is a disconnect between the way medical information is presented and the way people make decisions. 

For example, the risk of dying on the table during carotid endarterectomy (a vascular surgery procedure that removes plaque from the lining of your carotid artery) is 2 percent. In one of Reyna’s studies, some patients undergoing the surgery estimated their chance of dying as 10 percent, while others estimated as little 0 percent or no risk at all. Even though zero is numerically closer to two than ten is, someone who estimates 10 percent has made a more informed choice because that person grasps the important bottom-line: the surgery involves some risk.

But Reyna has found that gists are only as good as a person’s level of knowledge or understanding. For instance, the gist that “condoms block the exchange of bodily fluids” leads people to overestimate condoms’ effectiveness against sexually transmitted diseases, because it does not take into account infections that are transmitted by skin-to-skin contact, such as human papilloma virus. In this case, the bottom line is that some infections are transmitted skin to skin, not via exchange of fluids.

Reyna wants to help bridge this disconnect and make sure patients have the kind of information they need to make solid, informed choices. She has created a web page that explains how her basic research can help patients and their physicians map our health care choices.

She also offers some tips:

  • Health providers should explain options qualitatively. Instead of relying solely on numbers, it’s helpful to explain probabilities verbally, stressing the bottom-line meaning of information.
  • Display information visually. Simple bar graphs and pie charts help patients extract important information without getting hung up on memorizing the details.
  • Tailor the format to trigger the appropriate gist. Frame messages and choose the most suitable visual formats to convey the bottom line.

Your flu vaccine will help…a little

It’s the time of year when everyone is lining up for the annual flu vaccine.  Doctor’s offices and employers are holding special clinics, and even many drug stores are offering a poke in the arm to prevent influenza this winter.  But do these vaccines actually work?

A systematic review of the literature says they do, a little bit.

The Cochrane Collaboration (one of our favorite resources here at EBL) reviewed 50 reports of the benefits of the influenza vaccine, including 40 randomized-controlled trials involving more than 70,000 people.

Before I explain the results, here’s a little background on the flu:  There are more than 200 different viruses that cause influenza with similar symptoms including fever, headache, cough and body aches.  It is difficult for vaccine-manufacturers to know which of these viruses will be active in any given year.  The World Health Organization does its best to predict what type of flu will be prevalent in a given season, and then recommends which viral strains should be included in vaccinations each year.

Under ideal conditions – meaning that the vaccine completely matches the active flu viruses – 33 healthy adults need to be vaccinated to avoid one person coming down with the flu. But the vaccine rarely matches the active flu viruses entirely. In more realistic conditions where the vaccine partially matches the active flu viruses, 100 people need to be vaccinated to avoid one set of influenza symptoms.

None of the studies showed that vaccines reduced the number of people hospitalized for the flu.  Also, studies show the vaccine caused one case of Guillian-Barré syndrome, a neurological condition leading to paralysis, for every one million vaccinations.

The bottom line:  The flu vaccine will reduce your chances of getting sick this winter, but provides no guarantees of completely avoiding the flu.

How children remember their worlds…and why

We all have early childhood memories – of a favorite relative, a special toy or an event that made a big impression.  They are fixtures we will carry throughout our lives. But how those early experiences become sealed into our minds? 

Research by Human Ecology faculty member Qi Wang helps explain this phenomenon. Wang, an associate professor of human development, runs the Social Cognition Development Laboratory, where she studies how people develop autobiographical memory and their sense of self.

We know from prior research that the process of sharing memories begins early in life. As soon as children become capable of using language, they begin to discuss past events with caregivers. But initially, they make very few spontaneous references to past events. Instead, their recollections are directed by caregivers’ questions about the past. It is not until children are 3 to 5 years old that they can engage in more detailed conversations about the past. Even then, they rely on adults to direct the conversation.

Wang’s research has delved into how parents’ conversations shape children’s memories. She has found children from different cultural backgrounds recall events differently based on their parents’ conversational style.

For example, American mothers tend to elaborate more on children’s own narratives, asking questions that focus on the child and providing additional details about past events. This values children’s participation and emphasizes the importance of individual experience. Hence, American preschool and grade school children provide more elaborate and detailed memory accounts that refer to their own roles and preferences.

By comparison, Chinese and Korean mothers are less likely to elaborate when talking about past events with their children. Instead, they are more likely to ask factual questions and refer to other people. This approach emphasizes interpersonal relations, moral rules and behavioral expectations. As a result, Asian children talk more about other people than themselves when remembering something, and they are more likely to remember daily routines.

These early memories are important because they shape children’s sense of self and the way they recollect events over their entire lives. (Wang has found these cultural differences appear to extend to adulthood.)

A few take-home messages for parents are caregivers are:

  • Consider your goals before starting a discussion with your child. What aspects of the event do you think is important for your child to remember?
  • Consider the type of events you wish to discuss with your child and their implications. Selecting social events would allow you to reflect on your child in relation with others, social norms, and behavioral expectations. Choosing a personal event would allow you to focus on your child’s experiences, thoughts, and feelings relating to the event.
  • Ask a lot of “wh” questions (e.g., who, what, where, when, why). Provide answers when the child does not remember. Avoid repeating questions, or “looking” for a right answer. Try not to create a test-like atmosphere.

You can find Wang’s work summarized in a paper created by Human Ecology’s Department of Human Development.

When every drop counts: The facts on public health during a drought

Throughout the history of the Earth, droughts spanning seasons or even years have taken their toll on plant and animal life.  In more recent U.S. history, a series of major droughts every 20 to 30 years have devastated farms, sparked wildfires and led to adverse health effects.

Although the literature contains well-researched articles on the aspects and implications of drought itself, there have been few fact-based inquiries into how drought affects public health in the United States. Until recently.

Last month, the Centers for Disease Control and Prevention National Center for Environmental Health published a guide to assist public health officials to prepare for and cope with drought in their communities. The document includes information about how drought affects public health, recommends steps to help mitigate the health effects of drought and identifies future needs for research and other drought-related activities.

Among the CDC’s recommendations is to identify the populations that are most affected by a particular adverse condition. For instance, immune-compromised people drinking contaminated well water are most at risk of contracting infectious diseases. Once the affected populations have been identified, public health departments should actively collect and analyze quantitative and qualitative data to help determine the extent of the public health threat and the best steps to mitigate it.

The publication also suggests additional research in numerous areas including identifying the health effects of reusing water, using surveillance data to determine which chronic disease are more frequently reported during a drought, and identifying pathogens that can be used as drought indicators.

Intrigued?  You can find the entire publication by clicking here.

Youth development and the 4-H program: A gateway to the evidence (and more)

When people hear the words “4-H program” they often think of the signature clover, the “head, heart, hands, and health” motto, and kids raising animals to show at the state fair. In fact, the 4-H program is one of the most extensive youth development programs in the world, involving millions of young people in a vast range of activities, including science and technology education, promotion of positive youth development, and community engagement. It also has a rich and interesting history over the past century.

Many studies have been conducted of the 4-H program. However, some of the research has been in unpublished form, including doctoral dissertations and master’s theses, which provide some very good research information but are hard to find. In addition, evaluations have taken place at the state or county level that may not be widely known.

Dr. Jan Scholl, Penn State University, has created two on-line searchable databases of 4-H studies. The first database, “Making the Best Even Better: Searchable Database of Over 800 4-H Research Studies, Agricultural Experiment Station Projects, Journal Articles and Proceedings and Other Papers,” is available at the following link: http://apps.libraries.psu.edu/agnic/state_national_search.cfm

The second database, “Making the Best Better: Searchable Database of 1700 4-H Graduate Studies,” is available at the following link: http://apps.libraries.psu.edu/agnic/thesis_studies_search.cfm

So if you are looking for the research base on the 4-H program, take a look at these sites. They are also looking for more studies to include, so if you’ve done one, submit your own!

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