Term 1 Flashcards
What does PICOT stand for
Patients / population - who will be participating
Intervention/interest (exposure) - what is being tested
Comparison - what is the comparison group
Outcome - what is the outcome or endpoint
time - when should outcome be measured
what are the two types of primary research designs
qualitative
quantitative
what are the three types of qualitative designs
interview
focus group
observational
what are the three types of quantitive studies
survey (closed)
observational analytic
experimental
what are the 3 subdivisions of observational analytic
cohort study
case-control study
cross sectional study
what are the two subdivisions of experimental studies
randomised control trials
non-randomised
what are secondary research designs
systematic review or meta analysis
what are the strengths of randomised controlled trials
provides evidence of causality
rigorous evaluation of single variable
what are the limitations of randomised controlled trials
resource intensive: costs time and money
needs a large number of participants - many studies underpowered
ethical challenges
what is the difference between a prospective and retrospective cohort study
In a retrospective cohort study, the group of interest already has the disease/outcome. In a prospective cohort study, the group does not have the disease/outcome,
what are the strengths of cohort studies
can establish population-based incidence
can study several outcomes for each exposure
can establish cause effect
what are the limitations of cohort studies
resource intensive: costs money and the
large number of people needed
loss to follow up
inefficient for rare conditions
what are the strengths of a case control study
small sample size needed
appropriate or studying rare conditions or those with long lag between exposure and outcome
what are the limitations of a case control study
exposure assessed after disease occurrence
reliance on records to determine exposure status
highly susceptible to selection bias
what is the purpose of cross sectional studies
document health status in specific population at a specific point
what are the strengths of cross sectional studies
provides estimates of prevalence of a disease
can identify population healthcare needs
easy fast and inexpensive
no follow up required
what are the limitations of cross sectional studies
cannot determine casual relationships
participants may provide social desirable answers
impractical for studying rare diseases
why would you use a qualitative study
useful for understanding patients experiences perspectives and views
what are the strengths and limitations of qualitative studies
strengths:
enables understanding of patients experiences, unpredictable and insightful findings
limitations:
difficult to generalise, sample selection based on certain experiences
small sample size
what are meta analysis / systematic reviews used for
answer a specific clinical question
combines results of previous studies to produce one overall measure of the effect of an intervention
what is the difference between descriptive statistics and inferential statistics
descriptive - techniques we use to describe the main features of a data
inferential - statistical inference is the process of using the value of a sample statistic to make an informal guess about the value of the population parameter
what is the difference between categorical and numeral data types
categorical - sex, blood type
number - age, weight, number of siblings
what are the two types of categorical data
nominal and ordinal
what are the two types of numerical data
continuous and discrete
what is the difference between nominal and ordinal
nominal - no natural ordering ie sex or blood type
ordinal are ordered in severity or disease stage
what is the difference between continuous and discrete data
continuous - no value limitation such as weight
discrete - whole values only such as hospital visits
what are some ways you can present categorical data
bar chart
pie chart
frequency distribution
what are ways you can present data that is numerical
histogram
box or whisker plot
what does a frequency distribution table show
the frequencies and percentages in each group or category
what do these plots/charts show:
bar chart/pie chart
scatterplot
box plots
box - display frequencies of categories (categorical data)
scatter - numerica data using two continuous variables
box plots - summary statistics for numeric data
what is positive / negative skew
Positive Skewness means when the tail on the right side of the distribution is longer or fatter. The mean and median will be greater than the mode
Negative Skewness is when the tail of the left side of the distribution is longer or fatter than the tail on the right side. The mean and median will be less than the mode.
what is the difference between the mean median and mode
mean = average
median - middle number
mode - most common number
what does the mean median and mode not tell us
the spread and range of data
what does the range do
indicates the extremes - min and max value
what is the standard deviation
average of values around a mean
the larger the SD the further away the values re from the mean ie greater spread of data