Research and Critical Appraisal Flashcards
What does PICO stand for?
Population Intervention/Issue Comparison Outcome Time
What are the types of clinical questions that may be asked?
- most appropriate assessment for client group
- treatment effectiveness
- cost
- client experiences and concerns
- likely course of disability/disease
List population factors as part of the PICO
age group, diagnosis, geographic location, gender
What is the issue in the PICO? What are some common issues?
what the population is exposed to.
Intervention, test/assessment and predictor of interest
What are some comparisons used in the PICO?
alternative intervention gold standard measure or nothing
What are some outcomes in the PICO?
reduction in symptoms measurement in impairment improved quality of life reduced number of deaths, reduced costs and improved service delivery
What does time mean when used in the PICO?
over what time period is of interest
List the boolean operators and what they do
AND - gives results with both subjects limiting the field
OR - gives results about variants of a PICO element broadening results obtained
NOT - prohibits irrelevant results coming up
What is the process of acquiring evidence?
- begin with clearly defined clinical question
- conducting comprehensive and efficient searches using the PICO
- searching in the right places
- choosing the right evidence and right research design
What are the two main sources of evidence?
- filtered: already appraised resources
- unfiltered: sources not appraised
List filtered sources of evidence
Cochrane library, OT seeker, clinical guidelines, PEDro, Trip etc.
List unfiltered sources of evidence
CINAHL, Medine and PsychInfo
What are some filtered research designs?
systematic reviews, critically appraised topics and critically appraised individual articles
What are some unfiltered research designs?
randomized control trials, cohort studies, case series/reports and case-controlled studies
What are the types of research designs?
systematic reviews, critically appraised topic, randomized control trials, cohort study, case-control and cross-sectional study
What is a systematic review?
an article in which the authors have systematically searched for, appraised and summarized all of the medical literature for a specific topic.
What is considered the best research design?
systematic reviews
What is a critically appraised topic?
a short summary of an article from the literature to answer a specific clinical question
What is a randomized control trial?
a group of patients is randomized into experimental groups and are followed up for variables/outcomes of interest
What research design is considered the ‘gold standard’ of trials?
Randomized Control Trials
What is a cohort study?
Includes the identification of two groups of patients - one receives the exposure of interest, the other does not. Cohorts are followed to obtain the outcome of interest
What is a case-control study?
identifying patients who have the outcome of interest and control patients without the outcome and looking to see if they had the exposure of interest
What is a cross-sectional study?
sample population at some point in time and determine factors associated with outcome by measuring them to see who has the outcome or comparing between the established test and new test.
What is quantitative research?
provides numerical results and statistics to support or refute a hypothesis to focus on absolute or relative probabilities of events occurring.
What is qualitative research?
provides word data, themes and theories to provide a detailed description of beliefs knowledge or experiences. Gains insider’s view into the situation and thus tend to be more indicative than defined and confirmatory.
What may quantitative research be used to determine?
- intervention effectiveness
- diagosis
- prognosis
- causation
What are typical qualitative research designs?
systematic reviews, randomized control trials and cohort studies
What may qualitative research be used for?
understanding meaning, experiences and other phenomena
What are typical qualitative research designs?
grounded theory, ethnography and phenomenological
What research design would be useful in determining the effectiveness of an intervention?
Randomized Control Trial
What research design would be useful in diagnostic screening?
cohort study where all subjects receive the study test and gold standard test to assess the accuracy of the test.
RCT to assess effect of test on health outcomes
What research design would be useful in determining prognosis?
longitudinal cohort study
What research designs would be useful in determining aetiology and risk factors?
- RCT
- cohort for rare exposure with common outcomes
- case-control for rare exposure with outcomes with common exposure
Why does using the right study design matter?
The way in which people are selected to be in a study, measurements that are taken about people and what happens to them while in the study will determine the results’ applicability to the clinical question.
What is bias?
tendency to favor one outcome over another
What is systematic error?
Any process occurring at any stage of an investigation tending to produce results which depart systematically from the true values
What are the different types of bias?
- allocation bias: inclusion of study objects
- measurement bias: during taking a measurement or recording of info
- blinding bias: does the conductor know the variables?
- confounding bias - other factors i.e. medications used at the time
What is the I level of evidence?
a systematic review of all relevant RCTs
What level of evidence has the least bias?
a systematic review of all relevant RCTs (level I)
What is the II level of evidence?
properly designed RCT
What is the III - 1 level of evidence?
Pseudo-randomized control trial
What is the III - 2 level of evidence?
comparative studies with allocation not randomised , cohort studies and case-control studies
What is the III - 3 level of evidence?
comparative studies with historical control, interrupted time series with no results
What is the IV level of evidence?
case series, post-test or pre/post-test
What are the 3 questions to ask when looking at the research?
1) What was the research question and why was the study needed?
2) What was the research design?
3) Was the research design appropriate to answer the research question
What is critical appraisal?
The process of carefully and systematically examining research to judge its trustworthiness ad its value and relevance in a particular context
What are the principles of critical appraisal?
understand
- components that relate to quality of a study
- bias and types of bias
- gain experience in assessment of quality of a health promotion or public health study
- provides a rationale or justification of decisions
What is a study with minimal bias said to have?
internal validity
What is validity?
The degree to which a result from a study is likely to be true and free from bias
What is internal validity?
The extent to which the observed effects are true for people in a study
What can influence the level of bias in a study?
- data collection methods
- withdrawals and drop-outs
What is external validity?
generalisability and applicability of the evidence
What results should be considered for external validity?
results from an internally valid study
What does appraising the methodological quality of evidence include?
- consider how the study has been designed: sample size, blinding, bias, randomization and controlling for confounding factors
Explain the difference between level of evidence and quality of evidence.
- Level of evidence: about the design of the study determined using an evidence hierarchy
- Quality of evidence: how well the individual study was conducted determined by your critical appraisal of it.
What should the introduction in a reliability paper include?
describing the measurement, procedure under investigation and its relevance to clinical practice. Should briefly outline what is known from previous studies about instrument’s reliability and should justify the importance of the study
What are the three issues of samples?
patient characteristics, assessor characteristics and sample size
What must participants in a study be?
- heterogenous on the variable being measured
What are the negative factors of homogeous samples?
little participant variation produces lower reliability which may lead to incorrect conclusions
