Theme 6 - the different types of research and experimental methodologies Flashcards
What are the two types of research?
-qualitative research
-quantitative research
give 3 components of qualitative research
-concerned with words, meaning and experiences so no stats
-data generated typically through observations, questionnaires and interviews
-exploratory in nature used to develop an initial understanding rather than provide conclusive evidence
give 3 components to quantitative data
-concerned with numbers and stats
-data is generated through rigorous experimental means and through tight control of variables
-results can be generalized to the wider population and may be used to make important decisions
give 3 examples of qualitative research
-how happy and content are you with your life choices?
-what colours do you see looking at this particular image
-interview transcripts from patients who suffered an egg-related trauma
what would be at the top of the hierachy of evidence? What would be at the bottom?
top: systematic reviews
bottom: background info, expert opinions
give examples of quantitative research
-what is the Quality of Life score for patients who are blind?
-what percentage of cell loss occurs in glaucoma with and without treatment with drug X?
-what is the typical VA loss associated with egg related ocular trauma as recorded on a snellen chart
in what two ways do clinical and epidemiological research take place in patients
either by doing
-intervention/ trial studies that involve giving something to patients
-observational studies where patients are put into groups and observed rather than manipulated
are most epidemiological studies observational or interventional?
observational
give an example of how an epidemiological study can be interventional
studying the effects of chlorine in drinking water (its looking at making a big change to a community)
what are epidemiological studies for?
looking at:
-frequency
-distribution
-changes over time
-cause of a disease
what are the steps involved in clinical trials?
-phase 1 - testing the safety profile of the drug normally done on healthy patinets
-phase 2 - testing efficacy of a drug in a medium sized sample group (50-300)
-phase 3 - testing the efficacy of a drug in a very large sample (almost always a randomised controlled trial (RTC))
there may be a phase 4 - where observational studies look at long term effects of the drug
what is a case study? where is it on the hierachy of evidence?
-a descriptive account of a particular patient case or group of cases with no control group for comparisons
-2nd to bottom on the hierachy of evidence
what is a cross sectional study and give an example
-a particular observation made at a specific point in time, often used in conjunction with other study types
- example being a survey is given out to your optometry patients after receiving a particular type of care
how is a case control study different to a case study?
case control has a control group whereas case does not
what is a case control study, give 2 examples
study begins with a particular outcome and then looks back to see what could have led to the outcomes presence or absence so is retrospective
-patients that have glaucoma and patients that dont
-glaucoma patients that responses to IOP lowering drops and those that did not
What is a cohort study? Give an example
a group of individuals with a common trait/ exposure are followed up over an extended period e.g. repeatedly following up a group of patients after cataract surgery to study their visual acuity progression or follow up smokers to determine any future health problems
what can you calculate using a cohort study?
relative risk
what are the drawbacks to a cohort study?
-expensive
-time consuming
-not recommended for disease with long latency
what are the two types of cohort studies?
retrospective and prospective
how is a retrospective cohort study different to a prospective cohort study?
in a retrospective cohort study,
-exposure and outcome have already happened
-data on exposures has already been collected and subjects were already grouped into exposed and non-exposed
whereas in a prospective cohort study,
-you start with the exposure instead of the outcome
how is a case control study different to a cohort study?
you have to use odds not relative risk
what is a prognostic study?
studying the prognosis of a disease depending on a variety of factors such as age, disease course, symptoms etc.
what is a diagnostic study?
a comparison of a new technique for diagnosing a disease with the current gold standard
what are the three types of correlational studies?
-case control
-cohort
-cross sectional
what kind of study is a correlational study an example of?
an observational study
what is an observational study?
a study with an observe and describe approach where the experimenter is in no way manipulating the variables or having a hand in allocating which subjects are in which particular group
what is a trial study?
a study that involves intervention where subjects are randomly assigned into the experimental or control group
what is a variable?
any factor, trait or condition which can change or exist in differing amount and should all be kept consistent so they dont influence the experiment
what is an independent variable?
the variable that is being manipulated e.g. treatment or placebo, it is the only difference between the experimental group and control group allowing cause and effect to be established
what is the dependent variable?
the variable that is being measured e.g. whether they receive treatment or a placebo
what is the difference between a partial- blinded study or a double blinded study?
a partial blinded study has only participants unaware they are receiving treatment whereas a double blinded study is where the participants are unaware they are receiving treatments as well as the experimenters and clinicians who are also unaware of whether they are administering a drug or a placebo
what is a randomised clinical trial?
a planned experiment testing the safety and efficacy of a particular drug or intervention
how is a randomised clinical trial different to a cohort study?
in a RCT the different groups exist because of your intervention whereas in a cohort study, there is no intervention
What are the similarities and differences between experimental design and Quasi experimental design?
they both have an independent variable that is manipulated while the dependent variable is measured.
quasi experimental designs have non randomly assigned participants whereas experimental designs are randomly assigned participants
give 3 example questions for quasi assigned experimental research design
-how effective is online teaching in comparison to face-face teaching
-how well do patients score on a vision-based test before and after treatment
-how well is a drug tolerated
how is a literature review different to a systematic review?
a literature review is more generic in the topics it covers whereas a systematic review is much more precise, extracts very specific data and attempts to find every study relevant to the proposed research question
