Volunteer for studies? Unscientific?

Dave!

Hey folks,

I'm just wondering here...

Is it unscientific if an experiment were to be carried out on a group of people who were particularly interested in science, research, etc.?

For example, if a group/society were created where people could join if they were interested in being subjects, and researchers could pick (at random maybe) from the pool, would that in some way bias the results? The fact that they are keen on science, etc.

For example if it were coordinated through the internet, then you would probably have a generally young population, and so the results obtained may be unapplicable (word?) to older people.

I suppose it would depend on the research/experiment though wouldn't it! If someone were surveying the people on their positions on certain things (drugs, abortion, etc), they would get more liberal responses, so it wouldn't be a good cross-section of the population. But if you are testing say responses to stimuli in different environments, the test could still be legit.

Thanks for any thoughts

AtomicHorror

I've personally volunteered for about 4 or 5 biology and psychology experiments. There was just a call for volunteers at the university. They needed people. They had some designated exclusion criteria I think but they weren't that formal. It all depends on the study of course. A clinical trial for example has to pass FDA criteria which has huge implications for study design and participant exclusion criteria.

r3nu4l

It would probably depend on the type of experiment.

Psychological or neurological experiments might become very biased towards a certain set of results because scientists, researchers and even those excited by science may have very similar logical thought processes or neurological wiring.

I'm not saying it would be biased but that there may be a potential there.

For clinical trials and general surveys I'd say it wouldn't be too biased

genegenie

It depends on how "generalisable" you want your results to be to the actual population. Unless you're picking people at random from the population, your measure of effect will always be biased away from the true value. Any method other than true random sampling will always introduce what's known as selection bias into your statistical analysis. Scientists volunteering for a study would be a highly selected group, unrepresentative of the general population. It wouldn't be unscientific to do this, epidemiological studies look at particular groups of people all the time. It just means that your results aren't generalisable to the whole population as they only reflect what's going on within the group you studied.

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

r3nu4l wrote: »

For clinical trials and general surveys I'd say it wouldn't be too biased

I disagree with this... The randomised controlled trial is the gold standard in clinical trials so that the results are more likely to be generalisable (how many times have I said that word now? :rolleyes:) to the entire population at risk, e.g. for a new drug/treatment.

As for general surveys, again you'd be taking the opinions of a highly selected group who are likely to differ from the general population in their socio-economic status, education, beliefs and attitudes etc. For example, I believe (correct me if I'm wrong) that a higher proportion of scientists are atheist than in the general population.

r3nu4l

genegenie wrote: »

I disagree with this... The randomised controlled trial is the gold standard in clinical trials so that the results are more likely to be generalisable (how many times have I said that word now? :rolleyes:) to the entire population at risk, e.g. for a new drug/treatment.

What I mean is that if you take a group of scientists who wish to volunteer for a randomised clinical trial they are no more or less likely than the general population to have different baseline values for things such as hypertension, diabetes, previous exposure to certain viruses...

Their basic biology is just the same as anyone else. However, no clinical trial will ever solely recruit scientists (for fear of any bias) so it's safe to assume that this would not be an issue. I see nothing wrong with the idea of gathering in one place, people interested in participating as subjects in research. Certain pharma companies would love to use a resource such as that.

As for general surveys, again you'd be taking the opinions of a highly selected group who are likely to differ from the general population in their socio-economic status, education, beliefs and attitudes etc. For example, I believe (correct me if I'm wrong) that a higher proportion of scientists are atheist than in the general population.

I see where you are coming from and there is a potential for bias. However, if you have a survey relating to "investment opportunities" and you go to Cabra when looking for results they will be very different to the ones you would get if you went to Ballsbridge! Market research agencies know this and therefore very carefully select participants for inclusion in the final analysis.

so once again, the OP asks whether it would be useful to have such a database of persons interested in participating in research. Again, I say yes. Market research agencies would love to have this sort of database available.


Also, socio-demographics are becoming less important in science in Ireland, imo. There are huge numbers of working and middle-class people in science. Where a bias would be indicated would be in specific surveys related to science in Ireland. A survey on preferred brand of baked beans is unlikely to be affected.

So while I take your point, I say that the people conducting trials (CRO's etc) and surveys (MRO's) are unlikely to simply use one population for their study. They would be happy however to use some of these people as part of a pool for studies.

We should also consider that quite often the Government do seek out the opinions of scientists and what better place would there be than from a database of scientists who are gathered solely to participate in surveys etc?

I myself participated in a Government sponsored survey investigating why Irish scientists left Ireland to work in other countries and what could be done to attract us back.

genegenie

r3nu4l wrote: »

What I mean is that if you take a group of scientists who wish to volunteer for a randomised clinical trial they are no more or less likely than the general population to have different baseline values for things such as hypertension, diabetes, previous exposure to certain viruses...

But it's entirely possible that people (especially scientists) who choose to volunteer for a RCT or other epidemiological study (particularly one examining a certain health outcome) are better educated and more health conscious than the general population. Thus they may make different lifestyle choices such as exercising more, smoking and drinking alcohol less, eating more healthily, taking vitamin supplements etc. Their baseline levels of hypertension and type II diabetes could certainly differ from the general population because of this.

Previous exposure to certain viruses may not be hugely different in scientists, but perhaps they're more likely to be vaccinated? (Actually, as an aside, I'd say scientists would certainly have a different exposure to viruses and other microbes. Some scientists travel more, to conferences etc., or do more field work, or work with animals. A microbiologist would certainly be exposed to different types of microbes than would be typical of the general population. I for example worked in a probiotics lab, so the composition of my intestinal microflora would likely be different to that of someone who didn't. But this is all just my own speculation, I'm just throwing out ideas here!)

Of course through sampling and stratification it's possible to control for confounders such as these during analysis. The point I was trying to make is that results of a study will always be subject to a certain amount of selection bias if a true random sample from the general population isn't taken. Random sampling for the win!

r3nu4l wrote: »

However, no clinical trial will ever solely recruit scientists (for fear of any bias) so it's safe to assume that this would not be an issue. I see nothing wrong with the idea of gathering in one place, people interested in participating as subjects in research.

I see where you are coming from and there is a potential for bias. However, if you have a survey relating to "investment opportunities" and you go to Cabra when looking for results they will be very different to the ones you would get if you went to Ballsbridge! Market research agencies know this and therefore very carefully select participants for inclusion in the final analysis.

so once again, the OP asks whether it would be useful to have such a database of persons interested in participating in research. Again, I say yes. Market research agencies would love to have this sort of database available.

Also, socio-demographics are becoming less important in science in Ireland, imo. There are huge numbers of working and middle-class people in science. Where a bias would be indicated would be in specific surveys related to science in Ireland. A survey on preferred brand of baked beans is unlikely to be affected.

So while I take your point, I say that the people conducting trials (CRO's etc) and surveys (MRO's) are unlikely to simply use one population for their study. They would be happy however to use some of these people as part of a pool for studies.

Absolutely, excellent points and very well made! I didn't mean to imply that the OPs idea wasn't a good one, certainly it would be a very useful resource. Again I was just pointing out that you couldn't generalise the results gained from a study of only volunteer scientists to the general population.

r3nu4l

genegenie wrote: »

Thus they may make different lifestyle choices such as exercising more, smoking and drinking alcohol less, eating more healthily, taking vitamin supplements etc. Their baseline levels of hypertension and type II diabetes could certainly differ from the general population because of this.

As would an athlete, soldier...in theory (Steve Redgrave, olympic medallist has type II diabetes!). A certain science professor at Trinity College has a huge pot belly However, I see what you are driving at.

Some scientists travel more, to conferences etc.,

Travel reps travel too, so do business development officers (our own are in the Far East right now!).

or do more field work, or work with animals.

Farmers, vets, DSPCA officers...

A microbiologist would certainly be exposed to different types of microbes than would be typical of the general population.

Bakers, brewery workers and farmers are all exposed to pathogenic yeast and fungi...

But this is all just my own speculation, I'm just throwing out ideas here!)

I know, so don't take my points above too seriously. My own point is very similar to yours. There are plenty of career groups out there that are exposed to many different threats and therefore to conduct a trial on any one group of people without proper random sampling is madness

The point I was trying to make is that results of a study will always be subject to a certain amount of selection bias if a true random sample from the general population isn't taken. Random sampling for the win!

Absolutely

Absolutely, excellent points and very well made! I didn't mean to imply that the OPs idea wasn't a good one, certainly it would be a very useful resource. Again I was just pointing out that you couldn't generalise the results gained from a study of only volunteer scientists to the general population.

Agreed, Dave! It's no harm gathering such a group to discuss and participate in research but I would open such an effort to all people. Perhaps there could be discussion forums for scientists but the actual volunteering database would be much more valuable to research groups if it were open to everyone and was more representative of the general population.

I don't actually think genegenie and I disagree on anything we're just arguing semantics and pedantics