Forum

Clinical Trials

Hi there, been lookin into a number of clinical trials that have taken place over the years on http://clinicaltrials.gov and i would like to know if anybody can tell me why quite a lot of the trials have no results? Im talking about the trials that are said to be completed. I cant figure out why they would bother to do the trial if people cant see the results. Help appreciated thanks

It takes a long time to collate and analyse the data. I suspect that’s the main reason. Plus you have to write the thing up. There are a lot of 'i’s to dot and 't’s to cross. I used to work in the lab of a company that developed new ways of delivering drugs into patiens and learned a bit about clinical trials then and during my degree studies. I’ve probably forgotten more than I remember, and things may have speeded up over the years. The people who set up the company I worked for sold the company and set up a new one which created Sativex.

I looked at the website you mentioned and noticed that there is one that says ‘has results’. I don’t know how long it takes to get from that stage to the results being published.

It may be that, as with everything else to do with clinical trials, it just takes a long time. I’m not sure where the completed and published trial information is, and haven’t done too much searching. I know at least some published clinical trial results are posted on the MS Trust website.

It’s an interesting question, though! I hope we find out the answer.

Yeah it does take a long time, too long if im honest. I think there has to be a better system in place with these trials

On top of the time factor (see the post from EllenC, above), there could be another reason.

To a scientist, there are three types of result:
Highly Significant
Significant
Non-significant

Without a long boring lecture on Inferential Statistics, “Non-significant” means that the whatever-it-is on trial cannot be claimed to do whatever-it -was-supposed-to-do. Quite often that means a long hard look at the whole trial to see if there was any point at which something from outside could have messed up the figures. This could mean that the whatever-it-was needs to be run again, or that the statistical analysis need to be re-done from scratch, or that the whatever-it-was just plain did not wotk the way it was expected to.

There might be enough evidence that the procedure was flawed - and the trial needs to be run again. The evidence might suggest that the whatever-it-was has an effect, but not quite the one that the experimenters expected to find - and it now needs a different decision on what to publish, and where to publish it.

As a sort-of example, remember that the “Post-It Note” (yes, those sticky bits of yellow paper) is the result of a failed experiment.

Geoff

Doctor Geoff, your comment regarding post-it notes was so interesting I had to google… anyone else curious? Here’s a link that explains:

http://www.xperimania.net/ww/en/pub/xperimania/news/world_of_materials/accidental_discoveries.htm

Pat x

Yes, Pat, the Post-it note story is fascinating, isn’t it?

In Psychology, there is a general practice of discarding results that fall more than 3 Standard Deviations outside the group mean, One researcher did this and published a theory. Some years later, he got to thinking that he had discarded rather a lot of data, analysed all the discards, and totally revised his theory - and the revision is now the accepted theory.

Some years ago, I worked in a Government owned research facility (and it does not exist now) which had an “Ethics Committee”. Said committee was not concerned with the ethics of any experiment, but only with the Statistical Analysis - and they would not give their approval to any experiment which was not likely to produce a statistically significant result. I never submitted any proposal for my experiments to them (yes, I found a loopholethat related to the object of the experiments).

That is science for you.

Geoff

i know these clinical trials are a complex process however, i am wondering why the immediate results cannot be posted anyway? For talking sake, the clinical trial for stem cells as a way of repairing myelin in the brain and spinal chord. When this trial finishes the results should be pretty obvious in my opinion. Did people get better? how many people improved? etc. Can anyone briefly explain why this is not possible, if there is any reason.

There is a further possibility. If the trials are being funded by (shall we say) a major drug or biochemical company, they may have imposed a condition of secrecy on the trials. This would be required (from their point of view) so that they had time to see if the successful research could be translated into a viable product.

Yet another thing to consider is that researchers usually want to get a publication or two out of their work. On average, it takes about 18 months from submitting the paper until the journal is published. If the researchers go down the route of a peer-reviewed and published conference, this can quite easily be 6 to 9 months lead time. Once the results have been published, then the academic credit can be taken. The research establishments themselves may have a view as to how the results (if any) are published, as this can influence subsequent government funding.

Geoff