if all subjects in a study received CPR after a heart attack would it be reasonable to study other effects with a randomized controlled trial?
Added by Adam M.
Step 1
Since all subjects receive CPR after a heart attack, there is no variation in this treatment to compare against a no-CPR group. Show more…
Show all steps
Close
Your feedback will help us improve your experience
Adi S and 88 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Swor et al. looked at the effectiveness of cardiopulmonary resuscitation (CPR) training in people over 55 years old. They compared the skill retention rates of subjects in this age group who completed a course in traditional CPR instruction with those who received chest-compression only cardiopulmonary resuscitation (CC-CPR). Independent groups were tested 3 months after training. The table below shows the skill retention numbers in regard to overall competence as assessed by video ratings done by two video evaluators. Source: Robert Swor, Scott Compton, Fern Vining, Lynn Ososky Farr, Sue Kokko, Rebecca Pascual, and Raymond E. Jackson, "A Randomized Controlled Trial of Chest Compression Only CPR for Older Adults- a Pilot Study," Resuscitation, 58 (2003), 177-185.
Adi S.
Ethically, the health care professional has a responsibility to provide the best care (beneficence), minimize harm, respect for persons (informed consent), and treat people equally (justice). Does the act of enrolling a person in a randomized clinical trial counter these obligations? What are the implications for the patients in the placebo group? What are the implications for the patients in the experimental groups? Consider the following: A new cancer drug has been developed and is ready for clinical trials. The researcher has received IRB approval and informed consent is obtained. This new drug appears to be much more effective than the standard protocol. A randomized clinical trial is conducted with 50 patients assigned to the experimental group (the new drug) and 50 patients assigned to the control group or usual treatment (standard protocol). In the course of the clinical trial, the patients in the control group experience a significant increase in mortality rates compared to the experimental group. A) Write a potential hypothesis for this study and identify the variables (independent and dependent) B) Should the research study be stopped? Why or why not? C) Is there a favorable balance between benefit and harm? D) What would you recommend from an ethical perspective? Support your position.
Katlin K.
In 1948, Austin Bradford Hill, designed a study to test a new treatment for tuberculosis that at the beginning of the study there was no evidence whether it would be any better or worse than bed rest. He randomly assigned some patients who volunteered to be a part of this study to receive the treatment Streptomycin, an antibiotic. The other patients received only bed rest as the control group. Hill then observed the patients’ outcomes: which patients died and which recovered. The results of the study are shown below. Died Recovered Total Control 14 38 52 Streptomycin 4 51 55 Total 18 89 107 We use the following simulation test if there is a difference between the recovery rates under the two treatments: We write "died" on 18 index cards and "survived" on 89 index cards to indicate whether or not a patient died. Next, we shuffle the cards and deal them into two groups of 52 and 55, for control and treatment, respectively. We then calculate the simulated difference between the recovery rates in Streptomycin and control groups (pStreptomycin - pControl), and record this value. We repeat this simulation 100 times. The histogram below shows the distribution simulated difference between the recovery rates in these 100 simulations. Which of the following is correct? Choose all that apply (there are multiple correct answers). - The alternative hypothesis should be that there is a difference between the recovery rates under the two treatments. - The difference between the survival rates in the control and treatment groups appear to be simply due to chance. - Streptomycin treatment appears to be effective in treating tuberculosis since the observed difference in recovery rates would be considered unusual based on the simulation results. - If Streptomycin and bed rest are equally effective in curing tuberculosis, the probability of observing a difference in the recovery rates at least as high as the one observed is 2%. - Based on this study we can conclude a causal relationship between Streptomycin and better tuberculosis recovery rate. - Hill's study is observational. - The conclusion of this study is generalizable to all tuberculosis patients. - The alternative hypothesis is that the Streptomycin treatment is more effective than bed rest. - Streptomycin treatment does not appear to be effective in treating tuberculosis since the observed number of deaths in the treatment group would not be considered unusual based on the simulation results.
Sri K.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD