Question
Question: Two shots (Shotl and Shot2) were given to zebrafish with antibiotic levels measured (in mmoLL) after giving the shots. Shot was given at a low dose and at a mid-range dose; Shot2 was either given O not: The experimental design was balanced and included every combination of the two shots. We want to determine if giving these shots together is safe Or unsafe.What kind of experimental design is this? Explain.
Question: Two shots (Shotl and Shot2) were given to zebrafish with antibiotic levels measured (in mmoLL) after giving the shots. Shot was given at a low dose and at a mid-range dose; Shot2 was either given O not: The experimental design was balanced and included every combination of the two shots. We want to determine if giving these shots together is safe Or unsafe. What kind of experimental design is this? Explain.
Answers
Identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized block design, or matched pairs design. Currently, there is no approved vaccine for the prevention of infection by West Nile virus. A clinical trial of a possible vaccine is being planned to include subjects treated with the vaccine while other subjects are given a placebo.
So we have a population with the West Nile virus. Currently there is no vaccine, but that's why they're working to make one. So the best way to go about this would be to assign one group a vaccine And one group a placebo effect. Um, This would be a um, not a matched pairs design, not a randomized black design, since we're in blocking parts, but this would be a completely randomized design. Since we would know that the vaccine does work. And the best way to do this would actually be to implement a double blind procedure where neither the person given the vaccine or is it the vaccine and the person receiving the vaccine knows if it is the real vaccine.
So a prospective study means that we have a study on subjects over a like period of time. And you know these things can be like 10, 20 years or even like 50 years long or even as short as just a year. But anything that follows a subject throughout time is going to be a prospect of study um Randomized means that there are going to be a random designation of people to the treatments. Um In the example that we're looking at, that's going to be The group with try whole tried authority 30 year on me. I can't say it. And then a group with some sort of normal saline and dopamine and complete placebo group with normal saline. So we've got three different groups and you'll have people that are randomly assigned to those three groups out of a larger pool. And you split it up like that. That's how it's gonna be randomized now for a double blind study. Um This would mean that the experimenter and the person receiving at the patient the recipients. So the guy with the clipboard in the glasses and then you got the patients, they don't know what the patient looks like. Maybe we'll have a robe on there because they're getting injected with a needle. And the double blind part is that we don't know if this is going to have the placebo or the treatment or the sailing with dopamine. We don't we don't know what's in there, but that way they can make sure that the treatment is the only variable being evaluated and that kind of goes into placebo controlled. Um They just want that third group in the definition were given it's that third group to see. Um Well did the saline have an effect on its own? Because the second group had some dopamine which was going to make the person feel good after they got there. Treatment maybe it's an injection. I don't know. I just use the syringe to really make sure that we understand that this is the treatment being applied.
What strikes us in this statement is the HIV Trials Network is conducting a study to test the effectiveness off to different experimental HIV vaccines on the subjects will consist of 80 pairs of twins. £80 off. Twins means this is a matched pairs design. This is a matched This is a matched first design, Yeah.
We know that P one is simply equal to 137 over 4 52 Which is equal to 0.3 23 AP two is equal to 31 over 99 which is equal to 2.313. No, the test hypothesis is it's not Just AP one is equal to B two. While the alternative hypothesis is that P one is less than PT two. The test statistic Z Is that P 1 -22 over P one Times 1 -11. Mhm and one plus two times 1, one is P two over and two, which is equal to -0.1. So since a is equal to zero point in a size, the critical value can be found to be negative 1645 from the standard normal table. And since Z is Greater than negative 1.645, we do not reject to know hypothesis. Therefore we can come we cannot conclude that a lower proportion of subjects in troop one experienced drowsiness as a side effect, then subjects and you too. So there's no causation