casual reasoning continued Flashcards
- Describe experimental trials
Experimental studies are ones where researchers introduce an intervention and study the effects. Experimental studies are usually randomized, meaning the subjects are grouped by chance.
- Describe bias and the effect it can have on an experiment
Sample bias can occur if the scientist or researcher fails to consider whether the sample, they are examining is truly representative of the population they wish to investigate. It is not always possible to eliminate sample bias in an investigation, what is more important, however, is that the scientist acknowledges these possible sources of sample bias when they report their results so that those reading the report can make informed decisions with this in mind
- What is randomisation?
A method based on chance alone by which study participants are assigned to a treatment group. Randomization minimizes the differences among groups by equally distributing people with particular characteristics among all the trial arms. The researchers do not know which treatment is better. From what is known at the time, any one of the treatments chosen could be of benefit to the participant.
- What is a placebo?
- It is an inert or pharmacologically mild ‘medicine’ often had a positive impact in a patient’s health and wellbeing
- The false treatment is named placebos
- Commonly used in trials for medical treatments and variations of placebos are often used in experimental trials that have many subjects
- The mere expectation of an effect can results in the supposed effect being overreported and in extreme cases can result in physiological changes even when no active treatment is given
- What are double- blind trials?
Double- blind trials are when even the administrator is unaware of the treatment a particular participant will receive.
- What are controlled experiments?
Controlled experiments must have a hypothesis, control group, intervention group, randomised selection, blinding and a placebo.
- What are the advantages and disadvantages of observational studies?
Observational studies are ones where researchers observe the effect of a risk factor, diagnostic test, treatment or other intervention without trying to change who is or isn’t exposed to it. Cohort studies and case control studies are two types of observational studies. Useful when RCT is unethical. Can utilise existing data. Easy to attain large sample sizes. Disadvantages include that there is no control for confounding variables.
- What are the advantages and disadvantages of experimental studies?
advantages:
- gain insight into methods of instruction
- intuitive practice shaped by research
- teachers have bias but can be reflective
- researcher can have control over variables
- humans perform experiments anyway
- can be combined with other research methods for rigor
- use to determine what is best for population
- provides for greater transferability than anecdotal - research
disadvantages:
- subject to human error
- personal bias of researcher may intrude
- sample may not be representative
- can produce artificial results
- results may only apply to one situation and may be difficult to replicate
- groups may not be comparable
- human response can be difficult to measure
- political pressure may skew results
- Outline randomised controlled trials
Eligible people are randomly assigned to one of two or more groups. One group receives the intervention (such as a new drug) while the control group receives nothing or an inactive placebo. The researchers then study what happens to people in each group. Any difference in outcomes can then be linked to the intervention.
- What are retrospective studies?
Starts with a random sample of human beings and divide them into two groups. One exhibiting the suspected effect, one not. See if there is a difference in rate of exposure to the suspected cause between the two groups.
- What are prospective studies?
Prospective studies are when a random ample of human beings are split into two groups one exposed to the suspected cause and ne not. See if there is a difference in rate of suspected effect over time between the two groups.
- What are case control studies?
Case-Control studies are usually but not exclusively retrospective, the opposite is true for cohort studies.
- What are cohort studies?
Cohort studies are usually but not exclusively prospective, the opposite is true for case-control studies.
- Outline confounding variables
A confounding variable is an “extra” variable that you didn’t account for. They can ruin an experiment and give you useless results. They can suggest there is correlation when in fact there isn’t. They can even introduce bias. That’s why it’s important to know what one is, and how to avoid getting them into your experiment in the first place. If an extraneous variable is casual and correlated with the independent variable in the study it is a confounding variable.
- What is the mechanism of reasoning?
Event/ pandemic occurs, gap of detected knowledge, field of research becomes trendy, dramatic increase of funding and scientific effort on the field, lack of knowledge is a cyclical process and form the fundamentals of research mechanism.
