A question about placebos in clincal trials

[Cairber]

A big argument of the anti vaccination movement is that the vaccine trials are not conducted "with a true placebo." The placebo group is usually given the vaccine without the virus in it. So, an example would be this trial:

rotavirus vaccine study

The 'placebo' group was given the following mixture:

sucrose, dextran 40, sorbitol, amino acids, Dulbecco's Modified Eagle Medium (DMEM), calcium carbonate, xanthan gum and water for injections.

(this is the vaccine minus the attenuated virus)

My question is, why is this done? Are there specific reasons why the placebo group is injected with more than sugar water or something?

[Rye]

I think it'll be to show the attenuated virus is the active ingredient. The mixture will also look just like the vaccine if it's got a slight colour or something. If the true vaccines only get equal to placebo effects, the false vaccines should get the same results without virus samples.

[Larz]

All the rest of those ingredients are a starters pack for the virus so as it has a better chance of taking hold in the subject. Essentially what Zuul said is right though, its all the ingredients except for the active part that is being tested so as you when you get the your data you know that it was the active part that caused a change and not just a "mind over body thing" or some strange phenomenon regarding the supposedly dependent variables of the serum.

[Cairber]

So their argument becomes that the trials that use this method and are testing the safety of the vaccine are flawed because the mixture is 'unsafe' (they usually point to studies of vaccines that have aluminum in them, so when they are tested, the aluminum remains in the placebo).

Not being too educated on research practices, I don't 100% understand the argument. But I guess they are saying that the placebo group could experience true reactions from the aluminum and that reactions in the vaccine group would be written off because the placebo group had the same reactions.

[Nova Andromeda]

So their argument becomes that the trials that use this method and are testing the safety of the vaccine are flawed because the mixture is 'unsafe' (they usually point to studies of vaccines that have aluminum in them, so when they are tested, the aluminum remains in the placebo).

Not being too educated on research practices, I don't 100% understand the argument. But I guess they are saying that the placebo group could experience true reactions from the aluminum and that reactions in the vaccine group would be written off because the placebo group had the same reactions.

-Testing the effect of the attenuated virus is entirely separate from testing the other components of a vaccine shot. Without reading the the study you cited in detail and just scanning it quickly they appear to addressed both concerns. First, their double blind study looked for differences between the placebo group (just the vaccine cocktail w/ no virus) and the real vaccine. It looks like they didn't find any significant adverse affects. Second, they added the new vaccine to the normal set of vaccines given to infants and found no increased adverse affects. Presumably, there is a large body of work detailing the effects of various standard vaccine cocktails, these effects would show up when the normal set of vaccines is given, and these affects have been shown to be safe (this last point has some complications such as problems with doing studies over several decades). I hope this helps.