"studies"

[BAU3]

I was just on the npr website reading about a"study" that was done (details not pertinent right now..) it cited that there was a 23 % increase risk of pertussis in children 0-16 whoo's parents refused vaxes.

So why can studies take this data and come out with this statistic, yet when they look at the # of children vaxed and the # of cases of autism etc and come up with absolutely NO corrolation?

Now, i know we're loking at diffrent kinds of studies, and I know that the link between,say in this case pertussis andvax/no vax and looking at cases of autism etc and vax are vastly different...it just strikes me that these studies can be so definative when they want to convince vaxes and so absolute when they want to dispute links between vaxes and adverse affects.

I guess my real question is: Is there anywhere that i can learn more about scientific studies and how they're conducted and how %'s etc. are calculated .. how the studies on, say vaxes and autism are done?

Sorry if this is rambl-y.. trying to nak and swat bugs and keep my mind in one place...

[lisalou]

Originally Posted by BAU3

I was just on the npr website reading about a"study" that was done (details not pertinent right now..) it cited that there was a 23 % increase risk of pertussis in children 0-16 whoo's parents refused vaxes.

So why can studies take this data and come out with this statistic, yet when they look at the # of children vaxed and the # of cases of autism etc and come up with absolutely NO corrolation?

Probably b/c there is no correlation or direct causal effect. You're sort of doing a huge leap of logic here and assuming that no vaccine studies show any negative effects. Kind of like if a (lack of vaccines) then b (increases risks of pertussis) therefore m (vaxes) then p (causes autism).

Originally Posted by BAU3

I guess my real question is: Is there anywhere that i can learn more about scientific studies and how they're conducted and how %'s etc. are calculated .. how the studies on, say vaxes and autism are done?

Yes you can start here

http://en.wikipedia.org/wiki/Scientific_method

Scientific method refers to bodies of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering observable, empirical and measurable evidence subject to specific principles of reasoning.[1] A scientific method consists of the collection of data through observation and experimentation, and the formulation and testing of hypotheses.[2]

Then once you understand the scientific method you can find the studies for whatever it is you want to know about and have a better understand of how to read the methodology, hypothesis and outcomes. You'll want a course in statistics if you really want to understand all of the numbers.

[carriebft]

Statistics is big, IMO. Things to really think about are stuff like statistical significance, risk ratio, etc.

So, if you look at the Generation Rescue phone survey which seems to be coming up a lot here and on blogs recently, you can see that there is some statistical issues with their conclusions, some very serious.

You can also see an issue with statistical significance in a new HPV study that came out saying it works for older women; I haven't pulled it apart yet but I did read a blog that demonstrated some pretty big errors.

[Ruthla]

I had a math teacher once tell me "statistics lie." You can usually bend and twist the numbers so that they're technically correct, but imply something that isn't really there. What's "definative" about these various studies isn't the studies themselves, but the tone in which the conclusions are written. Just look at the word choice, and the way it sounds, when you talk about parents "refusing" vaxes vs "declining" them.

Just from looking at the few details you've posted- why are they studying children up to age 16? Pertusses is usually little more than a bad cold in adults and older kids- it's only dangerous in infants. So what if more teens and preteens are getting pertussis when they're not vaxed? A much more relevent study would be pertusses rates in children 2-24 months old who's parents declined vax.

[lisalou]

Originally Posted by Ruthla

I had a math teacher once tell me "statistics lie." You can usually bend and twist the numbers so that they're technically correct, but imply something that isn't really there. What's "definative" about these various studies isn't the studies themselves, but the tone in which the conclusions are written. Just look at the word choice, and the way it sounds, when you talk about parents "refusing" vaxes vs "declining" them.

Just from looking at the few details you've posted- why are they studying children up to age 16? Pertusses is usually little more than a bad cold in adults and older kids- it's only dangerous in infants. So what if more teens and preteens are getting pertussis when they're not vaxed? A much more relevent study would be pertusses rates in children 2-24 months old who's parents declined vax.

And your post illustrates why it's always a good idea to go to source material before passing judgment on a text or study or whatever.

http://www.npr.org/templates/story/s...ryId=104523437

[Deborah]

Yes, whenever possible read the actual study. Sometimes the conclusions don't actually agree with the data--I remember one study where the data clearly indicated that one thing was happening and the conclusions slid right past it and came to a different conclusion.

Where can you get actual full-text studies? Some are free online, most are not. However, if you go to your local public library you can request full-text journal articles on interlibrary loan. It may take a few days, but you'll either get a paper copy or an online copy. Sometimes there is a small fee.

Have fun!

[carriebft]

Also a good resource are the clinical trials which you can find online a lot at sites like www.clinicaltrials.gov even when you can't get the whole thing there, you can get the information you need to then go to a library/university to get the rest.

[ccohenou]

Here is a great resource that describes different research methods in medicine, and explains their advantages and disadvantages:
http://library.downstate.edu/EBM2/2100.htm

[BAU3]

Originally Posted by ccohenou

Here is a great resource that describes different research methods in medicine, and explains their advantages and disadvantages:
http://library.downstate.edu/EBM2/2100.htm

aha.. thanks..thats what I was looking for..

And As ruthla pointed out the choice of words is huge... in this particular study "highly contagious" "deadly" "huge increase" "scary""common misconceptions"etc...

Anyway.. thanks for the replys. I'll do some reading now.

[ammiga]

Originally Posted by Ruthla

I had a math teacher once tell me "statistics lie." You can usually bend and twist the numbers so that they're technically correct, but imply something that isn't really there. What's "definative" about these various studies isn't the studies themselves, but the tone in which the conclusions are written. Just look at the word choice, and the way it sounds, when you talk about parents "refusing" vaxes vs "declining" them.

Just from looking at the few details you've posted- why are they studying children up to age 16? Pertusses is usually little more than a bad cold in adults and older kids- it's only dangerous in infants. So what if more teens and preteens are getting pertussis when they're not vaxed? A much more relevent study would be pertusses rates in children 2-24 months old who's parents declined vax.

Along these lines, I'd also want to know how everyone was diagnosed. It is pretty well known that if a non-vaxed kid comes in with a cough, doctors jump on the WC wagon. But, if a vaxed kid does, they will say bronchitis, croup, or other things. I would only be interested in a study where every person was actually tested for WC.

[BAU3]

This particular study was done looking at records of kids who were patients at a particular hospital. First they looked at those who had whooping cough.. then at their vax records..

But I think your absolutely right in that they would say "well, johnny has a bad cough... but oh, he's been vaxed for pertussis so its probably not that.."