Block 12 Flashcards
What type of study design would best help to answer a question about evaluation/acceptance of therapy? + Give an example question
“What do patient’s think of this therapy?”
Study design: qualitative research (systematic review / meta-synthesis also possible)
What type of study design would best help to answer a question about diagnosis? + Give an example question
“What is the best test to diagnose…?”
Study design: cross-sectional analytic study (systematic review also possible)
What type of study design would best help to answer a question about aetiology of disease? + Give an example question
“What causes this disease?”
Study design: cohort study or population based case-control study (systematic review also possible)
What type of study design would best help to answer a question about prognosis? + Give an example question
“What is going to happen if…?”
Study design: cohort study (systematic review also possible)
What type of study design would best help to answer a question about efficacy of treatment? + Give an example question
“What is the most effective way to treat…?”
Study design: RCT or systematic review of RCTs
What are the potential benefits of systematic reviews over individual primary studies?
- include all the available evidence to answer a question
- include unpublished research and non-english language publications
- increase the total sample size (and so increase levels of certainty and precision)
- indicate heterogeneity among studies
- permit sub-group analyses
- permit sensitivity analyses
What is bias?
The systematic introduction of error into a study that can distort results in a non-random way
What four aspects of a research study are assessed in an appraisal?
- bias
- applicability
- limits
- value
What is the point of appraising studies?
To identify whether the evidence the study provides is useful for answering your clinical question
What are the three discrete steps to appraising a study?
3 questions:
- are the results valid?
- what are the results?
- can I apply the results to my specific patient’s care?
What is study validity?
The believability / credibility of the results
Do these results represent an unbiased estimate of the truth, or have they been influenced in some systematic fashion to lead to a false conclusion?
What questions do you need to ask when considering the generalisability of study results to your patient/population?
- how similar are the patients in the study to my patient/s?
- can the local health service provide the intervention / diagnostic test that has been studied?
- what are the potential benefits and costs of the intervention? (including potential harms, financial implications of the intervention, and opportunity cost to others)
What should you consider when appraising whether a systematic review has tried to identify all relevant studies?
- hand-searching
- contacting authors / experts
- non-english language searches
- unpublished materials searches
- which databases were used
- if there was follow up from reference lists
What would make it more likely that a systematic review had only included high quality studies?
- individual studies assessed for quality
- quality assessment carried out by more than one reviewer
- use of standardised review criteria to assess quality
What should you consider when assessing whether a systematic review has reasonably combined study results?
- are the results of each study clearly displayed?
- are the results similar from study to study? (look for tests of heterogeneity)
- were reasons for variations in results discussed?
What should you consider about the results when appraising a systematic review?
- how are the results expressed (e.g. OR, RR, etc)
- how large is the size of the result
- how meaningful is the result
- how would you sum up the results in one sentence?
What should you consider when assessing the precision of a systematic review result?
- were confidence intervals reported?
- would you make the same decisions based on the upper confidence limit as you would on the lower confidence limit?
- is a p-value reported if confidence intervals are unavailable?
What should you consider when assessing if the findings of a systematic review can be applied to your patient/s?
- is the sample population different to your patient/s in a way that would produce different results?
- does your setting differ much from that of the review?
- can you provide the same intervention as the review in the setting that you are in?
When considering the important outcomes of a systematic review, the reviewers should consider the outcomes from the point of view of…
- individual patients
- policy makers and professionals
- family/carers
- the wider population
What is the maximum “Referral to Treatment” (RTT) time in England? How many patients should be treated within the target timeframe?
- 18 weeks
- 90% (Dep. Health)
What does the NHS Constitution (2010) say about wait times?
The patient has the right to access services within maximum waiting times
What are unconditional max. wait time guarantees? Are they good?
- wait time is same for everyone
- easy to operationalise
- contradict clinical prioritisation
What are conditional max. wait time guarantees? Are they good?
- wait time is conditional on something e.g. clinical need, severity of prognosis, likely benefit or other factor
- difficult to operationalise
- permit prioritisaton
How can you manage wait times in healthcare?
- set targets
- incentivise people to meet target (e.g. reward or sanction)
- give value to patient choice and include the private healthcare sector
- prioritise how long people wait depending on specific factors e.g. clinical need (2ww for sup. cancer vs. 18ww for susp. OA)
What are the five statutory principles of the mental capacity act (2005) ?
- presumption of capacity
- right to be supported to make their own decisions
- right to make eccentric or unwise decisions
- best interests
- least restrictive intervention
What is mental capacity?
- the ability to make a particular decision at the time the decision needs to be taken
- must be able to understand, retain, and use or weigh the information given about the decision and then communicate their decision
What are advance decisions to refuse treatment? ( = advance directives)
- an advance refusal for a specific treatment in the event that the individual does not have capacity to decide at the time
- cannot refuse basic care
- must be valid and applicable to be legally binding
What are the pros of advance decisions?
- respects autonomy
- encourages openness and forward planning
- provides a legal right to refuse treatment
- patient’s may be less anxious about receiving unwanted treatments in the future
What are the cons of advance decisions?
- difficulties verifying that the patient’s opinion has not changed since the AD was made
- hard to ascertain that the current circumstances are what the patient foresaw when they made the AD
- risk of patient being coerced into making an AD
- question as to whether patients can imagine future situations sufficiently vividly to make an informed decision about the future
What are critical interests?
things that really matter to a person, for example: relationships, personal identity, faith, valuing independence, valuing health etc
What are experiential interests?
things that people may enjoy or not enjoy doing day to day, for example: like going to the cinema, dislike going to the dentist
When critical interests oppose experiential interests, which takes precedent?
- Critical interests will take precedent
- e.g. don’t like the experience of going to the dentist, but critically value your health so you will go
What ethical dilemma does Dworkin pose re: advance directives?
- If a person loses capacity should the critical interests they held when they were well, over-rule the experiential interests in the present?
- e.g. If a life-long vegetarian gets diagnosed with dementia a year later requests a bacon sandwich for lunch, should it be given?
Outline the personal identity argument against advance directives?
- ADs should only be binding if the person making out the AD is numerically identical to the patient in the present (e.g. patient with advanced dementia)
- The writer of the AD and the patient are not numerically identical because their psychologies are radically different
- Therefore ADs should not be binding for people with dementia
What are the big five complimentary therapies?
- chiropractic
- osteopathy
- acupuncture
- herbal medicine
- homeopathy
Which CAMs are statutory regulated?
chiropractic and osteopathy
Which CAMs providers are registered professionals?
chiropractors and osteopaths
How many consultations per year across the CAMs big five?
21 million
Approximately how many chiropractic and osteopathy consultations per year?
7.5 and 7.3 million
What percentage of the UK population access a CAM practitioner appointment each year?
12-16%
What percentage of adults use some form of CAM in the UK?
20-28%
How do people access CAM treatment and what is the potential problem with this?
- 70% access CAM through self-referral
- potential to miss medical red flags if the therapist is not sufficiently trained
How are the majority of CAM therapies financed?
67% self-financed
For which conditions are CAM most frequently used?
- MSK 68% (mainly back pain)
Which types of CAM have evidence-based indications?
- chiropractic and osteopathy for low back pain +/- sciatica
- acupuncture for chronic tension-type headache and back-pain
- herbal medicine: specific preparations for specific conditions e.g. St Johns Wort for mild/moderate depression
What is confounding?
When a relationship between an exposure and an outcome is distorted by their shared relationship with something else
How can confounding be addressed in study design and analysis?
- restriction (exclusion)
- matching
- stratification
- multiple variable regression
How does restriction affect studies and the effect of confounding?
- must be designed in
- exclude participants with confounding factors
- less data
- difficult to operationalise when there are multiple confounders
How does matching affect studies and the effect of confounding?
- must be designed in
- most common in case-control studies: cases and controls are matched on the possible confounder e.g. deprivation
- useful for strong confounders (e.g. age, sex) but confounding must still be considered in the analysis
How does stratification affect studies and the effect of confounding?
- possible to add in at the analysis stage
- involves analysis of exposure:outcome association in different subgroups of the confounder (e.g. deprivation) to determine a measure of the confounder’s effect
- can adjust for confounding if number of variables involved is relatively small, but not for lots of variables at once
What are the gaps in getting evidence into practice?
- identifying need for knowledge
- discovery of that new knowledge
- synthesis of knowledge
- application of knowledge
- development of routine clinical actions or policy
What is the first gap in translation?
Basic research to late clinical trials
What is the second gap in translation?
Health technology assessment to healthcare delivery
What are potential facilitators of uptake of evidence?
- recommendation is easy follow, and compatible with existing norms and values
- social influence of immediate team and influential peers
What are potential barriers to uptake of evidence?
- recommendation requires new skills, and/or is complex
- lack of awareness of need for change
- over-estimation of self-performance
- negative attitudes towards the source of evidence, e.g. doubting credibility, overvaluing or reliance on other trusted/convenient sources
- time constraints
- limitation of necessary resources
- organisational culture not compatible with intervention
- social influence of immediate team and influential peers
Outline the quality improvement cycle
Plan Do Check/Study Act Set new standard
