Developing Research Questions & Study Designs Flashcards
What is meant by evidence-based medicine?
an approach to medical practice intended to optimize decision-making by emphasizing the use of evidence from well-designed and well-conducted research
What are the 5 A’s when practising evidence-based medicine?
- ASK a clinical question
- ACQUIRE the best evidence
- APPLY the evidence
- APPRAISE the evidence
- ASSESS the impact
What are the steps in the research process?
- Define the research problem/question
- Review the existing literature
- Formulate a hypothesis to be tested
- Select a research design
- Carry out the research
- analyse the data
- Interpret the results
- Report research findings
What is a research question?
A question that directs and focuses your research
What is the most important requirement for a successful study?
A clear and concise research question
What factors are determined by the research question?
- the population to be studied
- study design
- where the study will be conducted
- the time period for the study
- what data will be collected
What is the difference between background and foreground questions?
Background questions are about general information
Foreground questions are more specific
Why are foreground questions effective research questions?
They are more specific
They need a more strategic approach to searching the relevant literature
What are the 4 key categories of clinical questions (foreground questions)?
- aetiology
- diagnosis
- prognosis
- therapy
What does an aetiology question focus on?
The causes or risk factors associated with a disease or condition
What does a diagnosis and a prognosis question focus on?
Diagnosis - the accuracy or usefulness of a diagnostic tool/test
Prognosis - information about the probable outcome, progression of survivability of a disease or condition
What does a therapy question focus on?
the effectiveness and/or the risk associated with a specific intervention
Why is PICOt used?
It is a clinical tool that transforms an information need into an answerable clinical question
This allows EBM to be practiced
What does PICOt stand for?
PATIENTS/POPULATION - who is participating?
INTERVENTION/INTEREST - what is being tested?
COMPARISON - what is the comparison group?
OUTCOME - what is the outcome or endpoint?
TIME - when should the outcome be measured?
Why is a framework, like PICOt, used to develop a research question?
- to develop a focused clinical research question
- to identify key concepts
- to develop a search strategy that focuses on acquiring evidence relevant to a patient’s clinical needs
what are the FINER criteria used for?
Once you have a clear research question, the FINER criteria are used to assess whether this is a good research question
What does FINER stand for?
FEASIBLE - ability to recruit, measure/test, within time and resources
INTERESTING - to you, peers, colleagues
NOVEL - new findings or extensions of previous findings
ETHICAL - follows ethical guidelines
RELEVANT - to policy, practice, patients
What are the 2 types of primary research designs?
- Analytical
2. Descriptive
What are the 2 types of analytical studies?
- Experimental
2. Observational
What are the types of research that may be conducted in an experimental study?
- randomised control trials
2. non-randomised control trials
What are the types of research that may be conducted in an observational study?
- cohort study
- cross-sectional study (analytical)
- case-control study
What are the 2 types of descriptive studies?
- survey (cross-sectional)
2. qualitative
What are the types of research that may be conducted in a qualitative study?
- interview study
- focus group study
- observational study
What type of research would be conducted through a secondary research design?
Systematic review or meta analysis
What is a randomised control trial?
Participants in a population are randomly allocated into groups
The STUDY group receives the intervention
The CONTROL group does not receive the intervention
(placebo or other current treatment)
Why are randomised control trials often used?
They are the “gold standard” for establishing the effectiveness of an intervention
What is a non-randomised control trial?
All participants are given a treatment and followed for a period of time to see if they improve
There is no comparison against a control group
Why can the results of non-randomised control trials not be used as evidence that a treatment works?
Due to the placebo effect
It is impossible to tell how much of an improvement in a patient is due to the treatment itself
What are the strengths of randomised control trials?
- provides evidence of causality
2. rigorous evaluation of a single variable
What are the limitations of randomised control trials?
- resource intensive - cost time and money
- needs a large number of participants
- ethical challenges
What is a cohort?
A cohort is a group of people that share a characteristic or experience within a defined period
What is a cohort study?
A type of longitudinal study (years) that looks at the life histories of a specified cohort
What are cohort studies usually used to assess?
They evaluate a possible association between exposure and disease
How is a cohort study usually performed?
By following a group of individuals over a period of time
These groups were either exposed or not exposed to see whether they develop the disease/outcome of interest
What are prospective cohort studies?
They are studies conducted in real time
What is the main limitation of cohort studies?
They cannot show that one factor is the cause of another
There are so many potentially confounding factors involved
What is a retrospective cohort study?
Study using historical cohort data
It involves using data collected in the past to look at association between exposure and disease
what is a benefit of a retrospective cohort study over a prospective cohort study?
They take a much shorter time to complete
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 time and money
- needs large number of participants
- loss to follow up
- inefficient for rare conditions
What is involved in a case-control study?
You identify all cases (people) with the disease and some non-cases (no disease)
You look back to assess if they were exposed to something that may have led to the disease
What are the strengths of a case-control study?
- small sample needed
2. appropriate for studying rare conditions/those with long lag between exposure and outcome
What are the limitations of a case-control study?
- exposure assessed after disease occurence
- reliance on records to determine exposure status
- highly susceptible to selection bias
What is the purpose of a cross sectional study?
To document health status within a specific population at a specific point
The patients are not followed
How do cross-sectional studies vary from case-control studies?
They aim to provide data on the entire population under study
Case-control studies only provide data on cases (people with a specific disease/characteristic)
What is meant by point prevalence?
A cross-sectional study provides a snapshot to give the prevalence of a disease at a specific time and place
How are cross-sectional studies often carried out?
As questionnaire-based surveys
e.g. census
What are the strengths of cross-sectional studies?
- provides estimate of prevalence of a disease
- can assess population healthcare needs
- easy, fast and inexpensive
- no follow-up required
What is the major limitation of a cross-sectional study?
an association between exposure and outcome does not imply a cause-effect relationship
What are the other limitations of cross-sectional studies?
- cannot determine causal relationships
- participants may provide socially desirable answers
- impractical for studying rarer diseases
What is involved in a survey study?
Predetemined questions are presented to a ‘representative’ sample
This explores thoughts, views, feelings about something specific
What methods are used in a survey study?
- questionnaires (postal, online, face-to-face)
2. interviews (face-to-face, telephone)
What are the strengths of survey studies?
- easy to produce
2. easy, fast and inexpensive to conduct
What are the limitations of survey studies?
- only answer questions asked
- participants’ interpretation or context to response is missing
- low response rates
- participants may provide socially desirable answers
When are qualitative studies particularly useful?
For understanding patients’ experiences, perspectives and views
What are the strengths of a qualitative study?
- enables an understanding of patients’ experiences/perspectives
- unpredictable and insightful findings
What are the limitations of a qualitative study?
- difficult to generalise
there is a small sample size, as sample selection is based on certain experiences
What is a systematic review?
They are designed to answer a specific clinical question
They involve a protocol-driven, comprehensive literature review
What are the steps involved in a systematic review?
- formulating a review question
- defining inclusion/exclusion criteria
- selecting and assessing studies
- extracting data
- synthesising selected studies
- interpreting results to answer review question
What is a meta-analysis?
This involves combining the results of previous studies to produce one overall measure of the effect of an intervention
