This forum is about wrong numbers in science, politics and the media. It respects good science and good English.
Well, I found the pressure group involved, its the department of health. I also found the full text of the report, at:
I am not an expert on statistics. I can't fault the methods here, except to observe that the text admits they picked the best-fit methods to get the best result for them, and when the result was 'wrong', as in when the heavy drinkers seemed to be at less risk of obesity than those under the govt limit, they discarded it. Smokers seemed to be in less danger too, from my reading of the report. Am I the only person to actually read it, as opposed to the headline figures from the press release, which seem to have been enough for the BBC and the papers?
They seem to be basing a seven-year prediction, 2003-2010, on data from 2001-2003, if I read it correctly. Is that a good thing to do? Why don't they check a sample in 2006 to see where they are? Why do they give numbers of obese people in exact 7 digit numbers, when they worked from a 4-digit sample?
This link to a bbc report about denying fertility treatement to obese women smacks of eugenics. It horrifies me that it is coming to this and yet not a whimper of outcry in the blogosphere that I can see.
Reverse Eugenics surely - improving the human race by NOT breeding?
I'm no expert but one aspect of fertility that seem to be unchallenged is that being overweight at the time of attempted conception may have an adverse effect on fertility for some women. Presumably there is a good biological reason for this. The problem has presumably been identified because women who subsequently lose weight are more likely to become pregnant.
Now on that basis it seems that a first reasonable step to pregnanace would be to become as fit as necessary to initiate conception, carry and deliver at term. Preferably without abnormal (unaffordable) costs of interventions.
After that there may be something to debate, but whether that debate be about not offering IVF treatment to women whose physical state suggests, according to their own bodies perhaps, that pregnancy should be contra-indicated is another matter.
More logically, in my opinion, the debate should be about whether IVF treatment should be offered free on the NHS with its implied cost to society. Is it really justifiable as a human right for females? Does it not suggest interference with natural selection principles that may ultimately be damaging to the human cause?
And on a national level any fears about declining populations (which might justify fertility intervention) have surely been defrayed by the recent rapid immigration growth.
So can IVF treatment be justified at all, let alone for free?
I will now don my tin helmet and retreat to the nearest trench to await the incoming barrage for those comments. But in summary I cannot see how this could be considered to be eugenics unless there is some state intervention stipulating how the sperm donor is to be selected to improve the breeding stock.
I can't comment on the statistical methods in the "Forecasting Obesity to 2010" report but I notice that it's based on the "Health Survey for England 2003" study. This study was strongly criticised for its exaggeration of the childhood obesity problem last year by an organisation called SIRC ("Social Issues Research Centre", website http://www.sirc.org/). The criticism is detailed in a report which can be downloaded from SIRC's website :
Summary of report:
Obesity and the facts
New Study Questions True Prevalence of Childhood Obesity
Claims of obesity 'epidemic' are not supported by evidence ... 'Hype and exaggeration' of data may result in inappropriate health interventions
Beliefs that childhood obesity is at epidemic levels and is rising exponentially are no more than unsupported speculation, according to recent data from the annual Health Survey for England 2003, published by the Department of Health on December 14th 2004, and analysed by the Oxford-based Social Issues Research Centre.
The new analysis shows that
* BMI trends have been broadly flat for both boys and girls aged under 16 years in the period 1995 - 2003, with very modest increases in average BMI of around 0.5 for boys and 0.6 for girls.
* The UK National standard for assessing child obesity used by the Government's recent Public Health White Paper overstates the scale of the child obesity problem - 15.5% obese - compared to the less arbitrary International Standard - 6.75% obese.
* Although the rates of increase of obesity under both measures are broadly similar (60-70%), the difference between the numbers of children defined as obese is likely to have a significant impact on the appropriateness and scale of the measures to tackle the problem of obesity.
* There is no indication of any significant change in the number of children with chronic illnesses, including type II diabetes, over the past 9 years. The absence of any evident deterioration in the health status of children supports the conclusion that children are not becoming fatter as fast as is widely believed.
* The prevalence of obesity is strongly related to age. The 16-24 year age group - both males and females - is substantially less at risk of becoming obese than older age groups, and the incidence of obesity for males in this age range has declined very slightly in recent years. Those aged between 25 and 34 have the second lowest rates of obesity. Middle aged people and those of retirement age are the most 'at-risk' groups.
* More young men and women in the 16-24 age group have a 'desirable' BMI of between 20 and 25 than any other BMI category. Men of this age are twice as likely to be underweight as they are to be obese.
SIRC's report concludes: "We do no service to the people at risk of obesity-related morbidities in our society by 'hyping' their plight, exaggerating their numbers or diverting limited educational, medical and financial resources away from where the problems really lie. Banning advertising of 'junk food' to children and similar measures may be popular in some quarters, but they are unlikely to impact much on the generation of people in their 50s and 60s - those with vastly higher rates of overweight and obesity than children and young people."
"The Health Survey for England provides grounds for a serious re-think."
The impression I get with the obesity scare lobby is that they're borrowing a trick they've learned from the Green lobby: if you want political action on some issue that you're lobbying over, you exaggerate it as a problem that will affect todays children.
Thanks, Dave. Your information goes to confirm my suspicions (or support my prejudices, depending on how you look at it). I think one shouldn't accept scares like the obesity figures without having a look around. In this case, I don't see the obese kids in the numbers claimed. I DO see children who are far taller and fitter-looking than when I was their age, and I truly doubt how a coarse measure such as BMI can be applied to such a disparate range of shapes and sizes. I recall how my no. 1 son was above the 100th percentile(???) for height on the NHS growth charts when he was young. He's 6'5" now. He has never been the tallest in his class. His friends at school have had various growth rates, some were small until 15 or so, then shot up to over 6ft. I don't think small sample trend analysis over short periods can work here.
It amazes me continually that BMI is considered a reasonable measure of anything. What amazes me more is that reasonable people (even Jeb) will give it credance even though they should know better. Jeb has argued that "he felt better when he had a lower BMI". Although your height may vary a little over the course of your life, it is not likely to be that much. What that statement really means is "he felt better when he weighed less".
BMI is effectively Kg/m^2. This almost looks like a pressure, but has no relavance to a persons appropriate size. Density my be a useful number to use, but even that is a little iffy when it comes to people. The fact that this number is useless is becoming more clear now that kids are growing up with adequate resources. The reason childhood BMI is going up is because they do not lack for calories to feed growth. Even my parents generation (born 1944) scrounged a little for calories. We don't have to. People aren't evolving taller, they are just maximizing their potential through access to resources.
We can argue if that is a bad thing. If calories suddenly become scarce, people like me are going to be the ones in trouble. At the very least I will probably lose a lot of weight.