research exam 3: independent study; systematic reviews and review questions
systematic review: So, it will tell us - either it works or it doesn't work. Or maybe we don't know yet, maybe we do need ___ studies for a particular question. And sometimes it will tell us ___ it works best for and what ___ of the treatment might work best.
more who, version
Narrow question: disadvantages You may need to have ___ reviews to answer all the questions, or compare the treatment options relating to a condition. One way that Cochrane manages sets of narrow reviews is to publish ___ - these are brief papers that summarize the findings of multiple related reviews
multiple overviews of reviews
Apart from the type of review question, there is the issue of whether your question needs to be ___ or ___
narrow broad
___ reviews can synthesize evidence from sources such as interviews and focus groups to address questions other than effectiveness, such as how people experience an intervention, or how an intervention can be put into practice.
qualitative
what category of question: What are the barriers and facilitators to the implementation of lay health worker programs to improve access to maternal and child health?
qualitative
A(n) ___ review question is essential to your systematic review. It's important that you're clear about what your review will cover, as the question will define many of the subsequent steps of the review.
well-defined
features of systematic reviews that make them more helpful than single studies: (6)
-save the reader time -provide reliable evidence -resolve inconsistencies -ID gaps -establish that questions have been fully answered -explore differences between studies
The intervention review question will be along the lines of: (2)
"What is the value of Intervention X compared with Intervention Y for a particular group of people?" "What is the value of Intervention X compared with no intervention?"
-Systematic reviews highlight areas where there is not enough ___. They can identify ___ in knowledge which can be used to guide future research efforts.
evidence gaps
___ reviews address questions about how research is conducted and reported, including systematic reviews, and primary studies such as randomized trials.
methodological
Diagnostic test accuracy review question is likely to ask: (1)
"(How well) can Test X diagnose and detect Disease Y?"
Broad question: disadvantages The answers to broad questions can be ___, more difficult for authors to ___, and can miss some of the ___ possible in a narrower review.
complex conduct detail
Systematic reviews can help us explore the ___ between studies, identifying those factors that influence the effect of an intervention. This means that a systematic review could provide answers about the way a(n) ___ works in different variations, or different populations and contexts.
differences intervention
The review question will guide the ___ and ___ of your findings: Have the studies and results you have found ___ the question you set out to ask? Are there ___ or indirect answers? Which are the most important findings to highlight in your ___ and ___?
interpretation, presentation answered gaps conclusions, summaries
The aim of a(n) ___ review is to compare two or more interventions on a range of different outcomes, or to compare a particular intervention with no intervention at all.
intervention
Meta-analyses in___ reviews may be based on an incomplete selection of studies. If no meta-analysis is used, the results of multiple studies will be described in the text of the review, as a(n) ___
non-systematic narrative synthesis
The review question will determine how you go about your ___, and what kinds of studies you find. If you're not ___ enough about your question at this stage, you may miss papers that are really of interest to you, or find lots of papers that are not what you wanted.
search strategy clear
The hundreds of hours spent conducting a scientific study ultimately contribute only a piece of an enormous puzzle. The value of any single study is derived from how it fits with and expands previous work, as well as from the study's intrinsic properties. Through ___ the puzzle's intricacies may be disentangled.
systematic review
Systematic review: When you pull all those estimates, what you get is a(n) ___. The systematic part is that you have to be systematic in your ___ of the literature. You have to be systematic in the ___ that you use to evaluate. Because, anybody can write a review of the literature - I could pick my favourite 10 trials about whether garlic works for the common cold, because they shore up my idea about what the answer to that question is. But a systematic review means you're looking for all of the evidence, all of the evidence you can possibly find, to answer that question. Crunch the ____, get an answer.
systematic review searching methods numbers
Systematic reviews provide robust evidence because of authors: -A well-conducted systematic review has at least ___ authors (usually more), preferably combining experts in the ___ and experts in the ___ of systematic review. -Non-systematic reviews may have ___ or more authors, usually experts in the___ but not in the ___ of review
two topic of interest, methodology one topic of interest, methodology
review question video: For me, I think, one of the main things that I've learned from the job that I've been doing over the past few years is how much ___ add there is in putting together, assembling a question that's got real ___ to the end user.
value utility
The review question will determine your ___ - that is, which studies are included in the review, and which are excluded.
eligibility criteria
___ reviews assess how well a diagnostic test performs in detecting a particular disease.
Diagnostic test accuracy
Systematic reviews include these features: -Conclusions that are grounded in the ___ in the review. -Detailed reporting of methods and results to ensure that the findings can be ___ experimentally. -Cochrane Reviews are periodically ___ to include new findings, although not all systematic reviews are updated.
evidence reproduced updated
systematic review: Then what we do is we bring together ___ the studies that have been conducted to answer that question. We appraise them to see whether we think they're ___ or not. And then we ___ their results together, so we get a complete picture of the body of evidence on that question
all reliable summarize
Systematic reviews provide robust evidence because of the following features: (7)
authors study protocol research question search strategy selection criteria critical appraisal synthesis
A systematic review uses robust methods to reduce ___ in the gathering, summarizing, presenting, interpreting, and reporting of the research evidence. The key characteristics of a systematic review are: -clearly stated ___ ; -pre-defined ___ criteria; -explicit, reproducible ___; -___ search of the literature; -assessment of ___ of included studies; -systematic ___ and ___ of findings.
bias objectives eligibility methodology systematic validity synthesis, presentation
Systematic reviews provide robust evidence because of search strategy: -A well-conducted systematic review has a ___ and ___ search strategy. Its sources include ___ electronic databases, and other sources of both published and unpublished literature, ideally without ___ restrictions. -Non-systematic reviews may have ___ detailed search strategy. ___ may not be clearly stated, and the search may not be ___ (e.g. limited to well-known articles in a language familiar to the authors).
comprehensibe, repeatable multiple, language no, sources, comprehensive
Broad question: advantages -Broad reviews are more ___, and may look at a broader group of ___, or a wider ___. -A well-focused systematic review question will be ____ enough to answer a useful question. This allows for some of the ___ that will always be observed in a field. However it must not be so broad that it doesn't make sense to consider all those studies together in one review
comprehensive interventions, population broad variations
Narrow question: advantages Narrower reviews are easier to ___, and easier to ___, looking at ___ specific intervention at a time.
conduct read one
Systematic reviews reduce ___. They can resolve ___ in practice caused when single studies produce conflicting results. For example, a systematic review of directly observed versus self-administered therapy for tuberculosis found a number of studies with differing conclusions. By examining the data from all studies together, the review was able to conclude that directly observed treatment actually does not improve the cure and treatment completion, which had some important implications for practice.
confusion inconsistencies
What's the difference between systematic and non-systematic reviews?
-Systematic review: uses robust methods to reduce bias in the gathering, summarizing, presenting, interpreting, and reporting of the research evidence. -Non-systematic reviews: typically invited contributions created by experts to provide an overview or broad summary of what is happening in a particular field; susceptible to bias. The authors may not clearly state the methodology used, and may be selective in presenting evidence to support a particular, pre-existing view.
For example, you might want to compare the effectiveness of imiquimod cream with Mohs micrographic surgery for preventing the recurrence of basal cell carcinoma of the facial skin. Can you identify the following components of the PICO format in this topic?
-participants: patients with basal cell carcinoma of the facial skin -intervention of interest: imiquimod cream -comparison: Mohs micrographic surgery -outcome: recurrence of the cancer
The four PICO components are all important, but they do not need equal emphasis in every review question. For example, if you are interested in exploring which of the various competing interventions works best for a particular stage of breast cancer, which PICO element should be defined very precisely in your question?
define the participants precisely, including the stage, and severity of breast cancer
what category of question: Can a measurement of ferritin in serum, or plasma be used to detect iron deficiency?
diagnostic test accuracy
Systematic reviews provide robust evidence because of research question: -A well-conducted systematic review starts by stating a specific question which may have all or some ___ (___, ___, ___, and ___) components . -Non-specific reviews may start from a specific question, or cover a very general topic area where the ___ is not stated
PICO (Population, Intervention, Comparison, and Outcome) hypothesis
what is PICO format for intervention reviews?
PICO stands for the four critical components of an intervention review question: Participants, Interventions, Comparisons, and Outcomes.
review question video: I think that the more ___ and ___ people are prepared to invest in defining the review question, always comes out in that particular section. So you get a clear sense not just about the clarity of the question, but the ___ of that question to the end user. So it's a section I feel we could all do a little bit ___ on. And it's a section, I think, it's an opportunity to say to somebody: this is why I'm doing the ___, this is why you should ___it, this is why people should ___it, why you should ___ it.
effort, time value better review, read, use, disseminate
4 components of a well-defined review question:
eligibility criteria search strategy analysis of the results interpretation and presentation
Systematic reviews clearly show when ___ evidence has been produced, and no further studies are needed to prove the effectiveness (or otherwise) of an intervention.
enough
When planning your review, you will need to think about all four components and define each one: -Participants: ___ -Interventions: ___ -Comparisons: ___ -Outcomes: ___
Who are you interested in studying in your review? What is the intervention or group of interventions you want to test? What will the interventions be compared to? What outcomes will tell you which intervention is the most effective?
what category of question: Can wearing compression stockings, compared to not wearing them, prevent deep vein thrombosis in people travelling on long-haul flights?
intervention
A systematic review is an attempt to answer a question. So, a common clinical question - somebody tells me that garlic is a really good thing to take for a cold. Usually you've got an ___ or some ___ strategy for a condition. That's the vast majority of our questions - ___ clinical questions. So, what a systematic review is attempting to do, is to find all of the ___ data that would address that question
intervention preventative simple relevant
main categories of review questions: (5)
intervention review diagnostic test accuracy review prognostic review methodological review qualitative review
what type of review question does PICO apply to?
intervention review question
Qualitative evidence can be incorporated into another review type, such as a(n) ___ review, or can be reviewed ___.
intervention, separately
what category of question: What is the effectiveness, safety, and acceptability of surgery versus medical therapy for heavy menstrual bleeding?
interventions
Non-systematic reviews are typically ___ contributions created by experts to provide an overview or ___ summary of what is happening in a particular field. The nature of non-systematic reviews means they are susceptible to ___. The authors may not clearly state the ___ used, and may be ___ in presenting evidence to support a particular, pre-existing view.
invited broad bias methodology selective
Either type of review (systematic, non-systematic) may include ___, if feasible and appropriate. This is a statistical method that summarizes the results of more than one study.
meta-analyses
Systematic reviews are generally considered to provide the most reliable form of evidence for the effects of a medical intervention, test, or marker. But are they always that reliable? This depends on two things: the ___ quality of studies included in the review; the quality of the ___ itself.
methodological systematic review
what category of question: What is the impact of study design (including RCTs versus observational study designs) on estimated effect measures?
methodology
Consider whether you wish to answer a ___ question, e.g. looking at one specific intervention in a specific patient group, or a ___ question, e.g. looking at all interventions to address a particular health condition, or something more complex like health system or community interventions.
narrow broader
Take your time: -It's worth spending time to think through the definition of your questions in some detail as you begin the systematic review process. Not only can this help you ___ your work, but a clear idea of the scope of your review will also help you avoid ___ later on. -By laying down your parameters ___ in advance, you reduce the risk of making decisions or changing your mind later, in a way that might be ___ by the results of particular studies.
plan, bias objectively, influenced
Here's another example. Your focus of interest might be on a particular drug for any stage of breast cancer. Which PICO element should be defined very precisely in this case?
precisely define the intervention, in this case the treatment formulation
___ reviews assess the probable course or future outcomes for people with a specific health problem.
prognostic
prognostic reviews include identifying important ___ factors that might influence the course of the disease.
prognostic
what category of question: In people with non-specific low back pain, what is the association between a person's expectation of recovery (including general outcome expectations, treatment expectations, and self-efficacy expectations) measured in validated scales, and disability outcomes?
prognostic
Systematic reviews provide robust evidence because of study protocol: -A well-conducted systematic review has a(n) ___ study protocol, which includes a detailed plan of rigorous methods agreed before the review begins, and is ideally underpinned by ___ research. -Non-systematic reviews have no such ___ , and may change the ___ used along the way to influence the results of the review
published methods, methodological protocol, methods
Systematic reviews provide robust evidence because of synthesis: -A well-conducted systematic review includes ___ (narrative) synthesis and/or ___ pooling of data in meta-analysis, with consideration given to the relative ___ and ___ of the included studies. -A non-systematic review may use similar methods, although some non-systematic reviews present only the findings of individual studies, without ___, or give ___ weight to all studies, regardless of precision and quality.
qualitative, quantitative precision, quality synthesis, equal
review question video: When we're looking at a review, we do the ___ assurance job. We often find ourselves going back to the ___. And we want to know what the original ___ was like, what the outcomes were, and so on... And we always stop to look a little bit in some depth at that section called 'Why it is important to do the review'. It's the ___, it's the bottom paragraph in the '___' section to protocol. And we always think it's quite illuminating.
quality protocol question rationale background
Systematic reviews provide robust evidence because of critical appraisal: -A well-conducted systematic review includes a systematic and thorough appraisal of the ___ or risk of ___ in the included studies. -In non-systematic reviews, the evaluation of study ___ and ___ can be variable or may not be done.
quality, bias quality, methods
As a systematic review author, you can't improve the ___ of the primary studies included in your review (although you can consider and discuss them), but you can ensure that your review follows best ___ . There are tools developed to assess the methodological quality of systematic reviews and you can find the links to two of them (AMSTAR, and ROBIS) in Resources.
quality, practice
Systematic reviews present a more ___ picture of the available evidence than any single study, which may or may not have found similar results to other studies on the same question. They aim to present a(n) __ , ___ picture of all the available evidence, which can then be used to support decisions in health care. For example, ___% of WHO guidelines include Cochrane Reviews among their references.
reliable unbiased, comprehensive 90
The review question will inform your analysis of the ___ of the studies you find: Which ___ do you want to measure? Are there specific ___ you want to explore? What ___ do you need to find in the included studies?
results outcomes issues information
review question video: When people put a lot of time and effort into thinking through that (the rationale)... they set out to describe what has brought them to this particular ___. And the really good reviews, I think, actually you can see the seeds planted in that particular bit of the review, that then come out in other bits. And that might be acknowledging ___ of effect in populations, and that then becomes a subgroup ___. It might be that they acknowledge a ___ over adverse events, and then you see where that plays out in the outcomes and the '___ of findings' tables.
review question variation analysis controversy summary
Systematic reviews provide robust evidence because of selection criteria: -In a well-conducted systematic review, the criteria for inclusion and exclusion of studies are ___ and agreed in ___. -This may not be the case in a non-specific review. There may be ___ specific criteria for selection, and the authors may be ___ in their choices
specific, advance no, subjective
Systematic reviews are an efficient way of bringing together a whole body of research to answer a specific question. This saves readers ___ and ___ required to locate and appraise research, as well as interpret results.
time, expertise
By specifying PICO components, you're also implying what you ___ be exploring, which is equally important. For example, you are not interested in comparing imiquimod cream with cryotherapy (freezing), or cases of basal cell carcinoma in locations other than the face. In most cases, you will be interested in a(n) ___ of outcomes that are important to patients, clinicians, and policy makers, rather than just one. Your outcomes of interest can be listed in more ___ later in the review process.
will not range detail
