Research questions and hypothesis
what is quantitative research lifestyle?
research question, research design, data collection, data analysis and results, study conclusions, wider implications (loop)
What does PICO stand for
Population
Intervention
Comparison
Outcome
H1 alternative hypothesis
This is your prediction of what could happen.
There effect is real and not just due to chance.
when and how data is collected
many different kinds of designs
experimental, correlational, cross-sectional
what are two special kind of variables?
independent variables, dependent variables
theories/clinical experience/stakeholder perspective
a set of principals that explain a particular topic.
can change over time in response to new research
what is population?
the characteristics and conditions of the group
# ages
# specific diagnosis
# severity levels
what is the null hypothesis?
There is no effect or no difference.
This usually the default situation.
explain cross-sectional design
data collected from all participants at the same point in time
different participants can represent different age groups
examine the prevalence of a condition
define dependent variables
the outcome that is being measured
is assumed to be dependent on the independent variable
measured but never manipulated
there can be multiple dependent variables
questions and aims are two sides of the same coin
define intervention
what is the assessment or intervention you are considering?
what does it mean when the null hypothesis is rejected?
It means that the null hypothesis was not correct and the hypothesis worked.
It means there is an effect/difference.
explain correlational design
investigates association btwn two or more variables
no direct manipulation of variables
observe what is naturally occurring without trying to influence it in ay way - cant infer cause and effect, only an association
define independent variables
predictor variables
assumed to have a direct effect on the dependent variable
manipulated by the experimenter
there can be multiple independent variables
can also be called active variables
what is a hypothesis?
predictions, usually based on theories or previous knowledge about a topic.
Specific predictions, worded in a way that can be tested with statistical tests.
hypothesis are not 'proven.' Instead, we attempt to disprove them with evidence (known as falsification)
Define comparison
what is the main alternative to the assessment or intervention approach
(i.e., placebo, different technique, different amount of treatment)
What does it mean when you fail to reject the null hypothesis?
there was no effect of the intervention
explain experimental
direct manipulation of independent variable to see effect on dependent variable
design controls for possible extraneous variables
tightly controlled designs mean cause and effect can be inferred
what are the stages of research
- frame the research question
- set a testable null hypothesis
- design the study and identify variables
- analyze the data
- assess significance of any statistical test
- interpret the result
Define outcome
what do you want to accomplish, measure, or improve
(i.e., improve use of grammar)
Why not accept the null hypothesis
there is uncertainty about absolute truth
We cant really know that the null hypothesis is absolutely true merely bc we did not find evidence to reject it.