Happiness Keeps You Sweet,
Trials Keeps You Strong,
Sorrow Keeps You Human,
Failures Keeps You Humble,
Success Keeps You Glowing,
But Only God Keeps You Going!! - Anonymous
Friday, December 19, 2008
Monday, December 08, 2008
How to output SAS dataset in Stata readable format
How to output SAS dataset in Stata readable format
One of ways is:
LIBNAME output xport 'c:\Projects\eye.xpt';
options validvarname=v6;
proc copy in=work out=output memtype=data;
select eye;
run;
options validvarname=v7;
One of ways is:
LIBNAME output xport 'c:\Projects\eye.xpt';
options validvarname=v6;
proc copy in=work out=output memtype=data;
select eye;
run;
options validvarname=v7;
Sunday, December 07, 2008
Effects of Cold Weather on Mortality
Effects of Cold Weather on Mortality
This is not an article about diabetes, but a different way of thinking about climate change. How about a "1°C" decrease of body weight by the way?
http://aje.oxfordjournals.org/cgi/content/abstract/168/12/1397?etoc
Weather-related health effects have attracted renewed interest because of the observed and predicted climate change. The authors studied the short-term effects of cold weather on mortality in 15 European cities. The effects of minimum apparent temperature on cause- and age-specific daily mortality were assessed for the cold season (October-March) by using data from 1990-2000. For city-specific analysis, the authors used Poisson regression and distributed lag models, controlling for potential confounders. Meta-regression models summarized the results and explored heterogeneity. A 1°C decrease in temperature was associated with a 1.35% (95% confidence interval (CI): 1.16, 1.53) increase in the daily number of total natural deaths and a 1.72% (95% CI: 1.44, 2.01), 3.30% (95% CI: 2.61, 3.99), and 1.25% (95% CI: 0.77, 1.73) increase in cardiovascular, respiratory, and cerebrovascular deaths, respectively. The increase was greater for the older age groups. The cold effect was found to be greater in warmer (southern) cities and persisted up to 23 days, with no evidence of mortality displacement. Cold-related mortality is an important public health problem across Europe. It should not be underestimated by public health authorities because of the recent focus on heat-wave episodes.
Wednesday, November 26, 2008
RESEARCH AND MEDICINE
RESEARCH AND MEDICINE - JAMA November 26, 2008, 300 (20): 2435
http://jama.ama-assn.org/cgi/content/full/300/20/2435?etoc
"Research signifies effort directed toward the discovery of laws and
principles through the systematic collection of new and better
correlations of existing data. It means the utilization of hitherto
latent or wasted energy. The aims of research are not culture, not
miscellaneous information, not a mode of leisurely meditation on the
origin of things, but mainly utility and service to mankind."
These statements by Theobald Smith, while general, apply especially to
research in the field of medicine. Research is too often considered as
peculiarly difficult, requiring unusual and special qualifications and
only to be indulged in by a certain few whose sole ambition is to gain
fame by making some important discovery. This is by no means true. The
methods are straightforward, natural, simple, common-sense methods, but
complete, thorough, orderly and precise. Research is work in which
absolute honesty is demanded on every hand, for lacking this its very
purpose is defeated.
The great discoveries and generalizations in science and medicine have
been made usually after years of systematic and conscientious labor. As
a rule they evolve rather than flash into existence in a moment.
Twenty-three years elapsed from the time Darwin first published notes on
the evolutionary theory till it emerged in its complete form-"The Origin
of Species." It is said that Bacon delayed the appearance of the "Novum
Organum" for twelve years, and each year added something. Harvey
withheld the publication of his views on the circulation for twelve
years.
All research profits and is made possible by work that precedes it. This
work may be of little significance and of no practical value in itself,
but taken in relation with other facts it may help to solve the most
mysterious and difficult problems and be of the greatest practical
importance. It is never safe to predict in regard to the significance of
facts. There is only one safe method and that was used by Darwin,
namely, to note every detail carefully, feeling sure that in the final
causal interpretation of phenomena each and every one of these details
will find its place and there be of great significance. The question is
too often asked: Of what use is this or that piece of work? If the
practical side is not clearly evident the whole is considered a waste of
time and worthless. The important questions to ask are: Is it true? Are
these statements of facts? Are these true principles? If so, the work is
amply justified. Of course there is a scientific perspective. All facts
are not of equal importance. Some stand prominently in the foreground;
others are mere subsidiary detail; but in the final picture, in the
complete interpretation, all are essential.
At present many physicians look on the work in the laboratory as
scientific because certain phenomena are here more carefully analyzed
perhaps than seems possible in a clinic or at the bedside. But the
spirit of true practical medicine is scientific. Its aims are utility
and service to mankind. Facts are being observed and correlated and
their meaning determined. The apparatus may be different, but the
methods are fundamentally the same as those of the laboratory. Why
should an accurate physical examination of a patient be less scientific,
for instance, than the chemical analysis of the blood or observations on
the biology of the tubercle bacillus? The ultimate aim is the same, and
though the end in view in the former is more immediate than in the
latter the difference is not as to justify calling one scientific and
the other non-scientific. Scientific medical research must not be
confined altogether within the walls of the laboratory; a large part of
it must necessarily be done there, for medicine draws on the more
fundamental sciences for aid, and this requires more or less elaborate
laboratory facilities. What is desired is the greater use by physicians
at the beside of the general methods in vogue in scientific
laboratories, where are demanded careful observations, painstaking
analysis, logical reasoning, accurate and systematic records.
"No great discovery in science is ever without a corresponding influence
on medical thought, not always evident at first, and apt to be
characterized by the usual vagaries associated with human effort"
(Osler1). Laboratory workers and practicing physicians should come
nearer together and attempt to understand each other better. Often pure
scientists and experimenters are inclined to be radical, sometimes
impractical, and liable to be carried away by fanciful theories. And
sometimes they are justified in letting their imaginations soar to
heights which physicians perhaps dare not attain; this not infrequently
leads to valuable working hypotheses that may bring forth important
facts.
On the other hand, the scientific man, the laboratory worker, should
realize that physicians must have at least one foot on solid ground;
they must be conservative yet tolerant of new ideas, always willing to
consider and apply them in legitimate ways; they must be sympathetic
toward the new, knowing that in time the grain will be sifted from the
chaff and truth appear.
1. The Growth of Truth. Harveian Oration, London, 1906.
JAMA. 1908;51:1700
Tuesday, November 25, 2008
Good Parents, Bad Results - US News and World Report
Good Parents, Bad Results
8 ways science shows that Mom and Dad go wrong when disciplining their
kids
8 ways science shows that Mom and Dad go wrong when disciplining their
kids
http://health.usnews.com/articles/health/living-well-usn/2008/06/12/good
-parents-bad-results.html
Good Parents, Bad Results
8 ways science shows that Mom and Dad go wrong when disciplining their
kids
By Nancy Shute
Posted June 12, 2008
Does your 3-year-old throw a five-alarm tantrum every time you drop him
off at day care? Does "you're so smart!" fail to inspire your 8-year-old
to turn off Grand Theft Auto IV and tackle his math homework? Do the
clothes remain glued to your teenager's bedroom floor, along with your
antisocial teenager, no matter how much you nag or cajole? Being a
parent has never been easy-just ask your own. But in this day of
two-earner couples and single parents, when 9-year-olds have cellphones,
12-year-olds are binge drinking and having oral sex, and there is
evidence that teens are more fearful and depressed than ever, the
challenges of rearing competent and loving human beings are enough to
make a parent seek help from Supernanny. Actually, there is something
better: science.
Related News
A Good Parent's Dilemma: Is Spanking Bad?
What's Happening to the American Family
One View: A Spanking Might Beat Ritalin
Discuss Being a Parent
Researchers have spent decades studying what motivates children to
behave and can now say exactly what discipline methods work and what
don't: Call it "evidence-based parenting." Alas, many of parents'
favorite strategies are scientifically proven to fail. "It's intuitive
to scream at your child to change their behavior, even though the
research is unequivocal that it won't work," says Alan Kazdin, a
psychologist who directs the Yale Parenting Center and Child Conduct
Clinic. Other examples:
* Yelling and reasoning are equally ineffective; kids tune out both.
* Praise doesn't spoil a child; it's one of the most powerful tools that
parents can use to influence a child's actions. But most parents
squander praise by using it generically-"you're so smart" or "good
job!"-or skimping.
* Spanking and other harsh punishments ("You're grounded for a month!")
do stop bad behavior but only temporarily. Punishment works only if it's
mild, and it is far outweighed by positive reinforcement of good
behavior.
As yet, few of the bestselling books and videos that promise to turn
surly brats into little buttercups make use of this knowledge. That may
be because the research goes on in academia-at Yale, at Vermont's
Behavior Therapy and Psychotherapy Center, and at the University of
Washington's Parenting Clinic, for example. Surprisingly, many family
therapists and parenting educators aren't up to speed on the research,
either, so that parents who seek professional help won't necessarily get
the most proven advice. Case in point: Just 16 programs designed for
treating kids with disruptive behavior have been proven "well
established" in randomized clinical trials, according to a review led by
Sheila Eyberg at the University of Florida and published in the January
Journal of Clinical Child and Adolescent Psychology. Kazdin, who for
years has pushed clinical psychologists to adopt evidence-based methods,
published a book for parents earlier this year: The Kazdin Method for
Parenting the Defiant Child. Other lab-tested tomes include Parenting
the Strong-Willed Child by Rex Forehand and Nicholas Long and The
Incredible Years by Carolyn Webster-Stratton.
These discipline programs are grounded in classical behavioral
psychology-the positive reinforcement taught in Psych 101. Researchers
have run randomized controlled trials on all the nuances of typical
parent-child interactions and thus can say just how long a timeout
should last to be effective or how to praise a 13-year-old so that he
beams when he takes out the trash. Who knew that effectively praising a
child in order to motivate her has three essential steps? They are: 1)
Praise effusively, with the enthusiasm of a Powerball winner. 2) Say
exactly what the child did right. 3) Finish with a touch or hug.
What else can parents learn from the science? Researchers say these are
the biggest common boo-boos:
1. Parents fail at setting limits
It would be hard to find a parent who doesn't agree that setting and
enforcing rules are an essential part of the job description. Yet faced
with whining, pouting, and tantrums, many parents cave. "The limited
time you have with your kids, you want to make it ideal for them," says
Forehand, a professor of psychology at the University of Vermont whose
evidence-based program is outlined in his book. "As a result, we end up
overindulging our kids."
But, paradoxically, not having limits has been proven to make children
more defiant and rebellious, because they feel unsafe and push to see if
parents will respond. Research since the 1960s on parenting styles has
found that a child whose mom and dad are permissive is more likely to
have problems in school and abuse drugs and alcohol as teenagers.
"Parents ask their 1-year-olds what they want for dinner now," says Jean
Twenge, an associate professor of psychology at San Diego State
University and author of Generation Me. "No one ever said that a
generation or two ago." Using surveys dating back to the 1930s, Twenge
has found significant increases in reported symptoms of depression and
anxiety among today's children and teenagers, compared with earlier
generations. Suniya Luthar, a psychologist at Columbia University
Teachers College, reported in 2003 that children who are showered with
advantages are more likely to be depressed and anxious and to abuse
drugs and alcohol than the norm. Luthar says that's probably because
those children are under a lot of pressure to achieve at school and
think that their parents value their achievements more than themselves.
They also feel isolated from their parents.
Rule-setting works best when parents give simple, clear commands and
discuss the family rules with kids well in advance of a conflict,
according to Robert Hendren, a professor of psychiatry at the Medical
Investigation of Neurodevelopmental Disorders Institute at the
University of California-Davis and president of the American Academy of
Child and Adolescent Psychiatry. A common recommendation for parents who
fear coming off as a meanie: Let the child choose between two options
when either choice is acceptable to the parent. A half-hour of Nintendo
right after school, then homework? All homework before game time?
Consistency is also key. "I have to be very strict with myself and go
over and tell him the rules and walk away," says Lauren Jordan, a
stay-at-home mom in Essex Junction, Vt., whose 4-year-old son, Peter,
would scream and hit Jordan and her husband, Sean, then kick the wall
during timeout. "It felt out of control." Jordan signed up with
Vermont's Behavior Therapy and Psychotherapy Center to learn Forehand's
five-week process.
The first week was spent just "attending" to Peter, watching him play
and commenting without telling the preschooler what to do. "He loved
it," says Jordan, whose older son has autism and has required an outsize
share of her energy. "I realized at that point that he needs this
one-on-one attention." Jordan then had to learn to ignore Peter's minor
bad behavior (such as screaming for attention while Mom is on the phone)
and to not rush in to scold him during a timeout. "Consistency is the
key. It's not easy," Jordan says. "But it's made our home a much happier
place."
2. They're overprotective
Teachers, coaches, and psychotherapists alike have noticed that parents
today can't stand to see their children struggle or suffer a setback. So
they're stepping in to micromanage everything from playground quarrels
to baseball team positions to grades. Even bosses aren't immune. One
owner of a New York public relations firm says he has gotten E-mails
from parents telling him that's he's making their child work too much.
The child in question is in his 20s.
"Many well-meaning parents jump in too quickly," says Robert Brooks, a
clinical psychologist in Needham, Mass., and coauthor of Raising
Resilient Children. "Resilient children realize that sometimes they will
fail, make mistakes, have setbacks. They will attempt to learn from
them." When parents intercede, Brooks says, "it communicates to the kid
that 'I don't think you're capable of dealing with it.' We have to let
kids experience the consequences of their behavior."
Otherwise, they may grow afraid to try. "I see a lot of kids who seem
really unmotivated," says Kristen Gloff, 36, a clinical and school
social worker in the Chicago area. "It's not that they're lazy. They
don't want to fail."
3. They nag. Lecture. Repeat. Then yell
If one verbal nudge won't get a kid to come to dinner, 20 surely will.
Right? In fact, there's abundant evidence that humans tune out repeated
commands. "So many parents think they have to get very emotionally
upset, yell, threaten, use sarcasm," says Lynn Clark, a professor
emeritus of psychology at Western Kentucky University and author of SOS
Help for Parents. "The child imitates that behavior, and you get sassy
talk."
Nagging also gives children "negative reinforcement," or an
incentive-parental attention-to keep misbehaving. "I was kind of
ignoring the good behavior, and every time he did something wrong, I
would step in and give him attention," says Nancy Ailes, a 46-year-old
stay-at-home mom in East Haven, Conn. She was frustrated with her
9-year-old son, Nick, who would melt down and throw things if the day's
schedule changed, drag his feet about cleaning his room or doing
homework, and call her "bad Mommy" if she complained.
Parent management training this spring at the Yale Child Conduct Center
taught Ailes and her husband how to use positive reinforcement
instead-to praise Nick immediately and enthusiastically. Now, when Nick
is picking up his toys in the family room, she sits down, watches, and
says: "Wow, that looks really nice!"
Ailes and her husband, David, also learned how to set up a reward system
with points that Nick can cash in for Yu-Gi-Oh cards and Game Boy time
and to back up the system with timeouts for bad behavior. Within three
weeks, Ailes says, Nick had made a complete turnaround. "Instead of
doing things that make people unhappy," she says, "you do things that
make them happy!"
4. They praise too much-And badly
It seems like a truism that praising children would make them feel good
about themselves and motivate them to do better. But parents don't give
children attaboys as often as they think, Kazdin says. And when they do,
it's all too often either generic ("good job!") or centered on the
person, not the task ("you're so smart!"). This kind of praise actually
makes children less motivated and self-confident. In one experiment by
Carol Dweck, a psychologist now at Stanford University, fifth graders
who were praised for being intelligent, rather than making a good
effort, actually made less of an effort on tests and had a harder time
dealing with failure.
"It's so common now for parents to tell children that they're special,"
says Twenge. That fosters narcissism, she says, not self-esteem. Twenge
thinks parents tell a child "You're special" when they really mean
"You're special to me." Much better in every way, she says, to just say:
"I love you."
5. They punish too harshly
Although spanking has been deplored by child-development experts since
the days of Dr. Spock in the 1940s, as many as 90 percent of parents
think it's ok to spank young children, according to research by Murray
Straus, a professor of sociology at the University of New Hampshire.
Kazdin and other behavioral researchers say parents commonly punish far
more harshly than they need to.
After all, it's not supposed to be about payback, though that's often
what's going on, says Jamila Reid, codirector of the Parenting Clinic at
the University of Washington. The clinic's "The Incredible Years"
program has been found in seven studies to improve children's behavior.
"Often parents come looking for bigger sticks. We tell parents the word
discipline means 'teach.' It's something to teach a child that there's a
better way to respond."
Consider the fine art of the timeout. Parents often sabotage timeouts by
lecturing or by giving hugs, according to Sheila Eyberg, a professor of
psychology at the University of Florida. Her Parent-Child Interaction
Therapy is used in many mental health clinics. Forehand and other
researchers have spent many hours observing the use of timeout as a
disciplinary strategy to determine exactly what makes it effective. The
key finding: Discipline works best when it's immediate, mild, and brief,
because it's then associated with the transgression and doesn't breed
more anger and resentment. A timeout should last for just a few minutes,
usually one minute for each year of age of the child.
Teenagers who have outgrown timeouts shouldn't lose a privilege for more
than a day. Beyond that, the child's attitude shifts from regretting bad
behavior to resenting the parent. "The punishment business isn't just
ineffective," Kazdin says. "It leads to avoidance and escape. It puts a
little wedge in the relationship between parent and child." Long
groundings also make it more likely that the parents will relent after a
few days. Better, Kazdin says, to ask the child to practice good
behavior, such as fixing something he damaged, in order to win
privileges back.
6. They tell their child how to feel
Most parenting books focus on eradicating bad behavior. But in study
after study, empathy for other people leads the list of qualities that
people need to successfully handle relationships at school, at work, and
in the family. Children need to think about how their own feelings will
be affected by what they do, as well as the feelings of others, says
Myrna Shure, a developmental psychologist at Drexel University and
author of Raising a Thinking Child. "That is what will inhibit a child
from hurting others, either physically or emotionally."
And parents, by telling children "you're fine" or "don't cry," deny
children the chance to learn those lessons. "The child learns empathy
through being empathized with," says Stanley Greenspan, a child
psychiatrist in Chevy Chase, Md., whose most recent book, Great Kids,
tells parents how to help their child develop 10 essential qualities for
a happy life. Empathy, creativity, and logical thinking top the list. A
simple "We're so sorry, we know how it feels" is enough.
"Modeling empathic behavior is really very important," says James
Windell, a counselor with the juvenile court system in Oakland County,
Mich., and author of 8 Weeks to a Well-Behaved Child. "How you respond
to your children's needs sets the stage. It's really easy to be a
supportive parent when they bring home a straight-A report card. When
they get a bad grade, that's when they really need our support."
7. They put grades and SATs ahead of creativity
An overemphasis on good grades can also distort the message about how
and what children should learn. "We like kids to learn rules, and we
want them to learn facts," says Greenspan. "We're impressed when they
can read early or identify their shapes. It's much harder for us to
inspire them to come up with a creative idea." Children who can think
creatively are more likely to be able to bounce back if their first idea
doesn't work. They also know it can take time and patience to come up
with a good solution. The goal, says Greenspan, is not to have a child
who knows how to answer questions but one who will grow up to ask the
important questions.
Parents can help their children become independent thinkers by asking
open-ended questions like: Can you think of another way to solve the
problem with your teammate? Or ask a whining preschooler: Can you think
of a different way to tell me what you want?
8. They forget to have fun
"When I talk to families that aren't functioning so well, and I ask, how
often do you laugh together, they say: We haven't laughed together for a
long time," says Hendren. Those little signs of love and connection-a
laugh, a song shared in the car-are, he says, signs of health.
Wednesday, November 19, 2008
Predicting Prediabetes
Predicting Prediabetes
November 11, 2008 — An assessment tool known as Tool to Assess Likelihood of Fasting Glucose ImpairmenT (TAG-IT) is effective in screening patients for prediabetes, according to the results of a study reported in the November/December issue of the Annals of Family Medicine.
"Fifty-four million people in the United States have impaired fasting glucose (IFG); if it is identified, they may benefit from prevention strategies that can minimize progression to diabetes, morbidity, and mortality," write Richelle J. Koopman, MD, MS, from the University of Missouri in Columbia, and colleagues. "We created a tool to identify those likely to have undetected hyperglycemia....We then validated TAG-IT in a second population-based sample, and compared TAG-IT with BMI [body mass index] alone for the ability to predict IFG and undiagnosed diabetes."
Using existing data from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2004, this cross-sectional analysis examined 4045 US adults aged 20 to 64 years who were not diagnosed with diabetes but who had a fasting plasma glucose measurement. The investigators developed a logistic regression model predicting IFG and undiagnosed diabetes from characteristics that are self-reported or measured without laboratory testing. On the basis of this model, TAG-IT was developed, validated with use of NHANES III, and compared with BMI alone. Subsets based on race and ethnicity were also examined.
Factors that were most predictive of IFG and included in the final version of TAG-IT were age, sex, BMI, family history of diabetes, resting heart rate, and history of hypertension (or measured high blood pressure). Area under the curve (AUC) for TAG-IT was 0.740, which was significantly better than BMI alone (AUC, 0.644).
For an aggressive case-finding strategy, a score of 5 or higher yielded 87.0% sensitivity. If high specificity is preferred to minimize additional testing and false-positive results, a score of 8 (78.8% specificity) or 9 (87.9% specificity) could be used.
"The TAG-IT efficiently identifies those most likely to have abnormal fasting glucose and can be used as a decision aid for screening in clinical and population settings, or as a prescreening tool to help identify potential participants for research," the study authors write. "The TAG-IT represents an improvement over BMI alone or a list of risk factors in both its utility in younger adult populations and its ability to provide clinicians and researchers with a strategy to assess the risks of combinations of factors."
Limitations of TAG-IT were that it was developed from cross-sectional data and examines only the present risk for elevated fasting plasma glucose levels vs a future risk for disease, use of only fasting plasma glucose level as an outcome vs impaired glucose tolerance, and race or ethnicity not included as a predictor.
"TAG-IT can be readily and immediately applied in clinical settings, can aid in the identification of potential research participants with IFG, can be widely applied in practices using electronic health records, and can improve the efficiency of population-based screening, including community and Web-based applications," the study authors conclude.
The National Institute on Aging and the Robert Wood Johnson Foundation funded this study. The study authors have disclosed no relevant financial relationships.
Ann Fam Med. 2008;6:555-561.
Wednesday, November 05, 2008
Plastic Water Bottles
Plastic Water Bottles
http://www.thegreenguide.com/doc/101/plastic
Whether you buy bottled water or conscientiously tote some from home,
you'll want to avoid swallowing chemicals along with it. Particularly
for small children, whose bodies are developing, it's best to steer
clear of plastics that can release chemicals that could harm them in the
long term. Below, the plastics not to choose (check the recycling number
on the bottom of your bottle) and those that are safer:
Plastics to Avoid
#3 Polyvinyl Chloride (PVC) commonly contains di-2-ehtylhexyl phthalate
(DEHP), an endocrine disruptor and probable human carcinogen, as a
softener.
#6 Polystyrene (PS) may leach styrene, a possible endocrine disruptor
and human carcinogen, into water and food.
#7 Polycarbonate contains the hormone disruptor bisphenol-A, which can
leach out as bottles age, are heated or exposed to acidic solutions.
Unfortunately, #7 is used in most baby bottles and five-gallon water
jugs and in many reusable sports bottles.
Better Plastics
#1 polyethylene terephthalate (PET or PETE), the most common and easily
recycled plastic for bottled water and soft drinks, has also been
considered the most safe. However, one 2003 Italian study found that the
amount of DEHP in bottled spring water increased after 9 months of
storage in a PET bottle.
#2 High Density Polyethylene
#4 Low Density Polyethylene
#5 Polypropylene
Best Reusable Bottles: Betras USA Sports Bottles, Brita Fill & Go Water
Filtration Bottle, Arrow Canteen
Better Baby Bottles: Choose tempered glass or opaque plastic made of
polypropylene (#5) or polyethylene (#1), which do not contain
bisphenol-A.
Tips for Use:
*Sniff and Taste: If there's a hint of plastic in your water, don't
drink it.
*Keep bottled water away from heat, which promotes leaching of
chemicals.
*Use bottled water quickly, as chemicals may migrate from plastic during
storage. Ask retailers how long water has been on their shelves, and
don't buy if it's been months.
*Do not reuse bottles intended for single use. Reused water bottles also
make good breeding grounds for bacteria.
*Choose rigid, reusable containers or, for hot/acidic liquids, thermoses
with stainless steel or ceramic interiors.
For more info, see Product Reports on "bottled water" and "baby
bottles."
Friday, October 31, 2008
NHANES Tutorials
NHANES Tutorials
http://www.cdc.gov/nchs/tutorials/index.htm
Basic Tutorial
Continuous NHANES tutorial
Everything you want and need to know about analyzing continuous NHANES
data is now available in a web-based product. The Continuous NHANES
Tutorial is designed to help users navigate through the dataset. Users
can browse through different modules to gain insight into NHANES data.
Supplemental Tutorials
NHANES III Tutorial
This tutorial will orient you to NHANES III data, guide you through
preparing an analytic dataset, and explain the nuances of the survey
design. Users already familiar with Continuous NHANES data and
interested in using NHANES III data should use this tutorial. New users
of NHANES data should complete the Continuous NHANES tutorial before
beginning this tutorial.
NHANES II Tutorial
This tutorial will orient you to NHANES II data, guide you through
preparing an analytic dataset, and explain the nuances of the survey
design. Users already familiar with Continuous NHANES data and
interested in using NHANES II data should use this tutorial. New users
of NHANES data should complete the Continuous NHANES tutorial before
beginning this tutorial.
NHANES I Tutorial
This tutorial will orient you to NHANES I data, guide you through
preparing an analytic dataset, and explain the nuances of the survey
design. Users already familiar with Continuous NHANES data and
interested in using NHANES I data should use this tutorial. New users of
NHANES data should complete the Continuous NHANES tutorial before
beginning this tutorial.
Wednesday, October 29, 2008
Developmental biology: Neither fat nor flesh (Brown and white fat)
Brown and white fat
In mammals, white adipose tissue stores fat, whereas brown adipose
tissue burns fat. Brown adipocytes have a common origin with muscle
cells, which could help explain their unusual function.
http://www.nature.com/nature/journal/v454/n7207/full/454947a.html
Thursday, October 16, 2008
Web Live Cameras for Fall Foliage (Autumn Leaf) and Autumn Color, 2008
Web Live Cameras for Fall Foliage (Autumn Leaf) and Autumn Color, 2008
The Rocky Mountains Over Banff- Alberta, Canada - This view just may give you the first view of leaf color turn in aspens in North America. Canada's Banff National Park is seen here. With some luck you will get a clear day and a great view.
Acadia National Park- Maine, USA - View turning leaves on 40,000 acres of Atlantic coast shoreline. Mixed hardwood colors light up the green spruce/fir forest.
Selway-Bitterroot- Montana, USA - The Selway-Bitterroot real-time digital camera system is installed outside of the Stevensville USFS Ranger Station, Montana. The camera views Crown Point, 7 miles to the northwest and overlooks the third largest wilderness in the lower 48 .
Glacier National Park- Montana, USA - There are now six outside digital cameras located in Glacier National Park. You can curser over each link to see an updated quick shot.
Great Smoky Mountains National Park - Look Rock Cam
Great Smoky Mountains National Park - Purchase Knob Cam - North Carolina, USA - The Great Smoky Mountains National Park offers views via Look Rock Tower and Purchase Knob. These digital cameras offer some of the best autumn views of the Smoky Mountains.
Dolly Sods Wilderness- West Virginia, USA - The Dolly Sods Web camera system was installed in the USFS Bearden Knob air quality monitoring compound in November 2003. The camera views the Canaan Valley and Mt. Port Crayon, 13 miles to the south.
The Nation's Capitol- Washington D.C., USA - This web cam view is from the Netherlands Carillon looking east toward the Lincoln Memorial, the Washington Monument and the Capitol Building.
Mt. Washington- New Hampshire, USA - Web cam view of part of the Presidential Range of the White Mountains, the highest mountain in New England.
Brasstown Bald- Georgia, USA - Web cam view from Georgia's highest point near Blairsville.
Mammoth Cave National Park- Kentucky, USA - View of Green River Valley looking north-northwest. The visual range is approximately 15 miles and overlooks a massive upland hardwood forest.
Shining Rock Wilderness, Pisgah National Forest, Near Ashville, North Carolina and the Blue Ridge Parkway - North Carolina, USA - A view of Cold Mountain from the largest wilderness area in North Carolina.
Penn State Campus- Pennsylvania, USA - Great campus fall foliage cams including Mount Nittany and Alumni Gardens.
New England Leaf Peeping Cams- New England, USA - Watch forests change color with About's Go New England Guide.
Old Faithful Geyser Wyoming, Montana, Idaho, USA - View of Old Faithful Geyser in Yellowstone National Park.
Fall Foliage Cams- The Entire USA - Another destination site for fall leaf viewing in North America.
by Steve Nix http://forestry.about.com/od/fallcolor/a/fall_web_cams.htm
Friday, September 05, 2008
How to set decimal place for SUDAAN
How to set decimal place for SUDAAN
There are two ways (in italic):
1) PROC CROSSTAB DATA=EYE DESIGN =WR;
SETENV DECWIDTH=3;
NEST STRATA4 PSU4/MISSUNIT;
WEIGHT MECWGT4;
SUBPOPN POPMEC=1;
CLASS DM2 OPDURL4/NOFREQ;
TABLE DM2*OPDURL4;
PRINT NSUM /*WSUM*/ ROWPER SEROW/STYLE=NCHS WSUMFMT=F10.;
RUN;
2)
PROC CROSSTAB DATA=EYE DESIGN =WR;
NEST STRATA4 PSU4/MISSUNIT;
WEIGHT MECWGT4;
SUBPOPN POPMEC=1;
CLASS DM2 OPDURL4/NOFREQ;
TABLE DM2*OPDURL4;
PRINT NSUM WSUM ROWPER SEROW/STYLE=NCHS WSUMFMT=F10.3;
RUN;
There are two ways (in italic):
1) PROC CROSSTAB DATA=EYE DESIGN =WR;
SETENV DECWIDTH=3;
NEST STRATA4 PSU4/MISSUNIT;
WEIGHT MECWGT4;
SUBPOPN POPMEC=1;
CLASS DM2 OPDURL4/NOFREQ;
TABLE DM2*OPDURL4;
PRINT NSUM /*WSUM*/ ROWPER SEROW/STYLE=NCHS WSUMFMT=F10.;
RUN;
2)
PROC CROSSTAB DATA=EYE DESIGN =WR;
NEST STRATA4 PSU4/MISSUNIT;
WEIGHT MECWGT4;
SUBPOPN POPMEC=1;
CLASS DM2 OPDURL4/NOFREQ;
TABLE DM2*OPDURL4;
PRINT NSUM WSUM ROWPER SEROW/STYLE=NCHS WSUMFMT=F10.3;
RUN;
Friday, August 15, 2008
Translating the A1C Assay Into Estimated Average Glucose Values -- Nathan et al., 10.2337/dc08-0545 -- Diabetes Care
http://care.diabetesjournals.org/cgi/reprint/dc08-0545v1
The results of the A1C-Derived Average Glucose study (ADAG), published
in Diabetes Care, have affirmed the existence of a linear relationship
between A1C and average blood glucose levels.
In light of the study results, ADA is recommending the use of a new term
in diabetes management, estimated average glucose, eAG. Health care
providers can now report A1C results to patients using the same units
(mg/dl or mmol/l) that patients see routinely in blood glucose
measurements.
A1c and average glucose level
A1c and average glucose level
The results of the A1C-Derived Average Glucose study (ADAG), published in Diabetes Care this month, have affirmed the existence of a linear relationship between A1C and average blood glucose levels. Prior studies using limited numbers of meter glucose readings primarily in type 1 Caucasian populations had been used in the past to estimate average glucose. The international ADAG study clarified the very close linkage using about 2700 glucose readings per subject per A1C measurement, and verified that the relationship holds in people with type 1 and type 2 diabetes, of all ages, of both genders, and across ethnic/racial groups. The “new numbers” are somewhat different than those in the old tables of A1C vs. average glucose.
In light of the study results, health care providers can confidently report A1C results to patients using the same units (mg/dl or mmol/l) that patients see routinely in blood glucose measurements. For more information about the ADAG study, a table of A1C and the corresponding estimated average glucose, an eAG calculator, and other materials, go to http://professional.diabetes.org/glucosecalculator.aspx
The relationship between A1C and eAG is described by the formula 28.7 * A1C – 46.7 = eAG.
A1C eAG
% mg/dl mmol/l
6 126 7.0
6.5 140 7.8
7 154 8.6
7.5 169 9.4
8 183 10.1
8.5 197 10.9
9 212 11.8
9.5 226 12.6
10 240 13.4
Monday, August 11, 2008
Physical activity in NHIS
Physical activity in NHIS
The purpose of this site is to describe the history of NHIS adult physical activity questions and provide tools for identifying, accessing, and using NHIS physical activity data, collected since 1975.
http://www.cdc.gov/nchs/about/major/nhis/physicalactivity/physical_activity_homepage.htm
Wednesday, August 06, 2008
Pre-diabetes, offical defined on March 22, 2002
http://www.hhs.gov/news/press/2002pres/20020327.html
-----Original Message-----
In this 2002 article "The Prevention or Delay of Type 2 Diabetes", the
ADA uses IFG and IGT, but not prediabetes.
But in early 2002 the DPP came out, and during 2002 prediabetes was used
pretty widely, including in articles/lettters by Venkat, Mike, Frank.
Don't know when the first use was (possibly much earlier) or who coined
the term.
By 2003, the ADA was using "pre-diabetes" in its clinical practice
guidelines.
The 2002 or 2003 web-only position statement on prediabetes seems to
have disappeared, as you mentioned. Might have a print out somewhere.
In any case, you can say that the term prediabetes, meaning IFG or IGT,
came into wider use in 2002 after release of DPP results.
Thursday, July 31, 2008
ScienceDirect Topic Alert: Diabetes
 |
| Topic Alert: 56 New articles Available on ScienceDirect |
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| More... Access all 56 new results in ScienceDirect for: pub-date > 2004 AND KEYWORDS (diabet*) OR title (diabet*) OR srctitle (diabet*) |
| Send my e-mail in plain text format |
| Modify or Remove My Alerts |
| Access the ScienceDirect Info site if you have questions about this message or other features of this service. |
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Tuesday, July 29, 2008
Relation Between Body Mass Index, Waist Circumference, and Death After Acute Myocardial Infarction
Relation Between Body Mass Index, Waist Circumference, and Death After
Acute Myocardial Infarction -- Zeller et al. 118 (5): 482 -- Circulation
Acute Myocardial Infarction -- Zeller et al. 118 (5): 482 -- Circulation
hee-haw, this article suggests we need measure both BMI and WC. There is
no war of BMI and WC anymore. Kidding, but I enjoy the view angle of
this article.
http://circ.ahajournals.org/cgi/content/abstract/118/5/482?etoc
This article suggest we need both BMI and WC.
Conclusions- Neither BMI nor WC independently predicts death after AMI.
Much of the inverse relationship between BMI and the rate of death after
AMI is due to confounding by characteristics associated with survival.
This study emphasizes the need to measure both BMI and WC because
patients with a high WC and low BMI are at high risk of death.
Monday, July 21, 2008
Public-Use NHIS Linked Mortality Files (Lochner K. AJE 168:336-344, 2008).
Public-Use NHIS Linked Mortality Files
<<Lochner_K_08_[NHIS_Mort_Files].pdf>>
Folks,
This paper shows the similarity in findings between using the public-use version of the NHIS Linked Mortality Files (released last September?) and the restricted use data available through the NCHS Research Data Center. The former had modified information that might otherwise be used to identify individuals. The authors ran some models and revealed that results can be reasonably close for their example. However they also stated: "Moreover, caution in using the public-use files is urged for researchers requiring more detail on timing of death or age or when examining the mortality patterns of small subgroups of the population, such as numerically small racial/ethnic minority groups, very old individuals, or young adults. This is particularly the case when cause-specific analyses of such numerically small demographic subgroups are performed." So the paper offers some good (and some bad) news.
Carl
Lochner K, Hummer RA, Bartee S, Wheatcroft G, Cox C. The Public-Use National Health Interview Survey
Linked Mortality Files: Methods of Reidentification Risk Avoidance and Comparative Analysis
Am. J. Epidemiol. 2008 168: 336-344; doi:10.1093/aje/kwn123.
http://aje.oxfordjournals.org/cgi/content/abstract/168/3/336?etoc
The National Center for Health Statistics (NCHS) conducts mortality follow-up for its major population-based
surveys. In 2004, NCHS updated the mortality follow-up for the 1986–2000 National Health Interview Survey
(NHIS) years, which because of confidentiality protections was made available only through the NCHS Research
Data Center. In 2007, NCHS released a public-use version of the NHIS Linked Mortality Files that includes a limited
amount of perturbed information for decedents. The modification of the public-use version included conducting
a reidentification risk scenario to determine records at risk for reidentification and then imputing values for either
date or cause of death for a select sample of records. To demonstrate the comparability between the publicuse
and restricted-use versions of the linked mortality files, the authors estimated relative hazards for all-cause
and cause-specific mortality risk using a Cox proportional hazards model. The pooled 1986–2000 NHIS Linked
Mortality Files contain 1,576,171 records and 120,765 deaths. The sample for the comparative analyses included
897,232 records and 114,264 deaths. The comparative analyses show that the two data files yield very similar
results for both all-cause and cause-specific mortality. Analytical considerations when examining cause-specific
analyses of numerically small demographic subgroups are addressed.
confidentiality; epidemiologic methods; health surveys; longitudinal studies; mortality
Wednesday, July 09, 2008
Ankle Brachial Index
Ankle Brachial Index (ABI)
-----------------------------------------------------------------
Reviews
-----------------------------------------------------------------
Ankle Brachial Index Combined With Framingham Risk Score to Predict
Cardiovascular Events and Mortality: A Meta-analysis
Ankle Brachial Index Collaboration
JAMA 2008;300 197-208
http://jama.ama-assn.org/cgi/content/abstract/300/2/197?etoc
-----------------------------------------------------------------
Reviews
-----------------------------------------------------------------
Ankle Brachial Index Combined With Framingham Risk Score to Predict
Cardiovascular Events and Mortality: A Meta-analysis
Ankle Brachial Index Collaboration
JAMA 2008;300 197-208
http://jama.ama-assn.org/cgi/content/abstract/300/2/197?etoc
Tuesday, July 01, 2008
American Fitness Index
The inaugural data report, "Health and Community Fitness Status of 16 Large Metropolitan Areas," is a snapshot of the state of health and fitness in America's 15 most populous metropolitan areas, plus Greater Indianapolis (the headquarter city of American College of Sports Medicine and WellPoint, Inc.).
Read more about the AFI launch here or download the data report.
Read the story as it was first reported in USA Today.
AFI WEB SITE NOW ONLINE
After a successful launch during the 2008 ACSM Annual Meeting, we also launched the AFI Web site at www.AmericanFitnessIndex.org.
From the site, you can learn more about the program, the methodology for analyzing the data, download the full and metro area-specific reports, and more.
Don't see something on the site you were expecting to find? Let us know by sending an e-mail to afi@acsm.org.
Be sure to bookmark the site and check back for news and updates on the program as we move from the pilot phase to the next level.
Monday, June 23, 2008
From the May 2008 EpiMonitor: Dr. Sharon Schwartz's reading list on individual and population causes of disease
Dr. Sharon Schwartz's reading list on individual and population causes of disease (EpiMonitor May, 2008)
More Reading On The Tension Between An Individual and Population Level Focus in Epidemiology
In sharing her comments about individual and population causes of disease, Columbia University’s Sharon Schwartz kindly shared the reading list from a course she teaches and identified the most directly relevant readings in bold. These references plus a book by Rose are provided below for readers who may wish to examine these issues further.
- Beaglehole R, Bonita R. (1998) Public Health at the Crossroads: Which Way Forward? The Lancet 351: 590-592.
- Diez-Roux AV. (1998) On Genes, Individuals, Society, and Epidemiology. American Journal of Epidemiology 148:1027-1032.
- Krieger N. (1994) Epidemiology and the Web of Causation: Has Anyone Seen the Spider? Social Science and Medicine 39:887-903.
- Levins R. (1997) When Science Fails Us Forests, Trees and People Newsletter 32/33: February, p. 1-18
- Lewontin RC. (2006) The Analysis of Variance and the Analysis of Causes. International Journal of Epidemiology 35:520-525.
- McKinlay, JB. (1997) A Tale Of Three Tails. Invited paper presentation at “Prevention: Contributions from Basic and Applied Research” conference cosponsored by the Office of Behavioral and Social Sciences Research (OBSSR) of the National Institutes of Health (NIH) and the Science Directorate of the American Psychological Association (APA), Chicago, August 15-18, 1997 p.1-23.
- McMichael AJ (1999) Prisoners of the Proximate: Loosening the Constraints on Epidemiology in an Age of Change. American Journal of Epidemiology 149:887-897.
- McMichael AJ. (1995) The Health of Persons, Populations, and Planets: Epidemiology Comes Full Circle. Epidemiology 6:633-636
- Pearce N. (1996) Traditional Epidemiology, Modern Epidemiology, And Public Health. American Journal of Public Health 86: 678-683.
- Rockhill B. (2005) Theorizing about Causes at the Individual Level While Estimating Effects at the Population Level. Epidemiology 16:124-129.
- Rose G. (1985) Sick Individuals and Sick Populations. International Journal of Epidemiology 14:32-38.
- Rose G. (1992) The Strategy of Preventive Medicine. Oxford University Press.
- Schwartz S and Diez-Roux A. (2001). Causes of Incidence and Causes of Cases: A Durkheimian Perspective on Rose. International Journal of Epidemiology 30:435-439.
- Schwartz S, Susser E, Susser M. (1999) A Future For Epidemiology? Annual Review of Public Health 20: 15-33.
- Shy CM. (1997) The Failure of Academic Epidemiology: Witness for the Prosecution. American Journal of Epidemiology 145:479-484.
- Susser M, Susser E. (1996) Choosing a Future for Epidemiology: I. Eras and Paradigms. American Journal of Public Health 86:668-673.
- Susser M, Susser E. (1996) Choosing a Future for Epidemiology: II. From Black Box to Chinese Boxes and Eco-Epidemiology. American Journal of Public Health 86:674-677.
- Wing S. (1998) Whose Epidemiology, Whose Health? International Journal of Health Services 28:241-252.
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