This is a great article on the Melbye study in which Brind comprehensively demolishes it.

http://abortion-not.org/brindmelbye.htm

You still don't get it Gadfly, I and many others don't care what Brind thinks, because he is quite obviously biased on this subject.
When I had a look at his websites, all the so-called medical experts, board members etc were not-for-profit organizations of pro-life, far-right, conservative, religious people....who are all just as biased as Brind, no doubt.

http://discovermagazine.com/2003/feb/feathated
" The vast majority of epidemiologists say Brind's conclusions are dead wrong. They say he conducted an unsound analysis based on incomplete data and drew conclusions that meshed with his own pro-life views. They say that epidemiology, the study of diseases in populations, is an inexact science that requires practitioners to look critically at their own work, searching for factors that might corrupt the results and drawing conclusions only when they see strong and consistent evidence. "Circumspection, unfortunately, is what you have to do to practice epidemiology," says Polly Newcomb, a researcher at the Fred Hutchinson Cancer Research Center in Seattle. "That's something Brind is incapable of doing. He has such a strong prior belief in the association [between abortion and cancer] that he just can't evaluate the data critically."

Hmmmm....who to believe?
Pro-life organizations , or Cancer Research Centres?

OK Suseonline. If these people are so sure of themselves let them debate him in public? They are like Al Gore on global warming who refuses to debate opposition experts in public.

These folks are the same. They have good jobs in the public service or academia and would probably be forced to resign if they backed Brind.

Before World War II nobody wanted to side with Winston Churchill because it meant conscription, rationing, compulsory labour. Most creature comforts were limited. It was easier to live in a fantasy world in which Hitler was not such a bad guy and you could reason with him. But two years later German bombs were falling on London.

Eventually the chickens will come home to roost here. Thousands of women will be on chemotherapy or having mastectomies or even dying. The people in these cancer organizations will take early retirement to escape the retribution that they deserve.

This debate is typical of any scientific discussion with contradicting evidence regaring scientific question (i.e. almost all science) but also politicized for some reason or another.

As Suseonline points out above, epidemiology is an inexact science, and requires a critical evaluation of ones own studies to accurately account for bias and other conflicting factors. The fact that Dr. Brind admits that he first came to the "belief" that abortion increases breast cancer risk, and then performed studies to "prove" this belief, shows that Dr. Brind's studies may be flawed, and especially that as a scientist, Dr. Brind has some serious shortcomings. That said, none of this means that his is necessarily incorrect (or correct).

However, as any real scientist should know, one study does not automatically invalidate another study, and there is never any way to really "prove something" in epidemiology or even other scientific fields (other than mathematics). One must look at the entire set of data and studies as a whole and evaluate whether there is a consistent, believable association.

So lets look at other epidemiological studies that show a consistent, believable association between a specific factor and disease and compare the the odds ratio claimed in the Huang study (OD=1.44).

Smoking and lung cancer OD=44
High cumulative life-time exposure to sunlight and skin cancer OD=47.6
Obesity and cardiovascular disease OD=20-59
Human papilloma virus infection and cervical cancer OD=45-150

Continued.

So what I am trying to show here are examples of factors that are generally accepted in the scientific community of significantly increasing the risk of disease. These studies have been performed by many, many groups and have shown a consistent and obvious effect in the vast majority of studies. Now compare to the claims made by Dr. Brind, where we have many studies, each showing small positive or negative effects, the vast majority not statistically significant. What does this mean? Well I believe that it means that currently there is no compelling evidence of the abortion-breast cancer link. This is what almost every reputable cancer, medical and scientific organization is also saying. If there is a real link, it is so small that even a minor additional factor not accounted for can completely change the outcome of the study.

The fact that Dr. Brind has an admitted predetermined bias, has selectively ignored data that disagrees with him and promoted data that agrees, and is knowing politicizing and misrepresenting scientific method to the general public shows that Dr. Brind has no absolutely no scientific integrity. Others with political ideologies will continue to point to studies that support their opinions, and their opponents will point to studies that support their own. A real scientist is able to objectively review all the data and say "I don't know". This wont win any public debates, but is how science works. Time to get back to basics Dr. Brind.

P.S. I wouldn't necessarily call a journal with an impact factor of 2.9 a "prestigious international journal". Perhaps just another example of Dr. Brind the political activist rather than an objective scientist.

Stezza, thanks for that. A useful summary.

R0bert