Chapter 11 - Reasoning About the Design and Execution of Research Flashcards
Scientific Method Steps:
Generate a testable question
Gather data and resources
Form a hypothesis
Collect new data
Analyze the data
Interpret the data and existing hypothesis
Publish
Verify results
Hypothesis:
proposed explanation or proposed answer to our testable question
In the form of an if-then statement, which will be tested in subsequent steps
Experimentation:
manipulating and controlling variables of interest
Observation:
involves no changes in the subject’s environment
Finer method:
method to determine whether the answer to one’s question will add to the body of scientific knowledge in a practical way and within a reasonable time period
Finer Method Questions:
Is the necessary research study going to be feasible?
Do other scientists find this question interesting?
Is this particular question novel?
Has someone asked this question before and published it?
Would the study obey ethical principles?
Is the question relevant outside the scientific community?
Basic science research:
research conducted in a lab, not on people
Easiest to design b/c experimenter has the most control
Control/standard:
acts as method of verifying results
Positive controls:
those that ensure a change in the dependent variable when it is expected
Negative controls:
ensure no change in the dependent variable when no change is expected
Placebo effect:
an observed or reported change when an individual is given a sugar pill or sham intervention
Independent variable vs, Dependent Variable:
Independent variable: variable that is manipulated
Dependent variable: variable that is measured or observed
What needs to happen in order for a relationship to be considered causal?
If the change in the independent variable always precedes the change in the dependent variable, and the change in the dependent variable does not occur in the absence of experimental intervention, the relationship is said to be causal
Accuracy (validity):
ability of an instrument to measure a true value
Ex: accurate scale should register a 170lb person as 170 pounds
Precision (reliability):
ability of an instrument to read consistently, or within a narrow range
Systematic error:
when bias is considered
How to overcome error from random chance?
Random chance can also introduce error into an experiment
Can be overcome by using a large sample size
Human Subjects Research:
- consists of what
- experimental approach
Consists of experimental and observational studies
Experimental Approach - b/c subjects are in a less-controlled conditions, the data analysis phase is more complicated than in laboratory studies
Randomization:
method used to control for differences between subject groups in biomedical research
Uses an algorithm to determine the placement of each subject into either a control group that receives no treatment, or one or more treatment groups
Blinded:
- definition
- what happens without blinding
- means they do not have information about which group the subject is in
- Without blinding, the placebo effect would be greatly reduced in the control group, but still present in the treatment group
Single-blind experiments:
only the patient or assessor (person who makes measurements on the patients or performs subjective evaluations) is blinded
Double-blind experiments:
the investigator, subject, and assessor all do not know the subject’s group