Critically Appraising Knowledge for Clinical Decision Making

Step three is deciding whether to believe what you found. This unit does it at the level of the whole body of evidence; units 6 and 7 come back to appraise particular designs, and both of them sit inside the framework built here. Two things to carry through. Appraisal has four phases, and the first is the one most people mistake for the whole of it — a rapid pass that decides only what is worth keeping. And synthesis is not a vote: ten weak studies do not outweigh two strong ones, because weighing is not counting. By the end you can ask the three appraisal questions and say why validity and reliability are independent; name the four phases and what each produces; say what you weigh when you weigh a body; explain why a level is not a verdict on a study; and say why synthesis is not a vote.

Seven videos setting up step three. The three questions — validity, reliability, applicability — recur through units 6 and 7, so they are worth fixing now.

Step three.

EBP 0451 Critical Appraisal Is Step Three

Appraisal is step three, and it takes the yield from step two as its input.

Why it defines the field.

EBP 0452 Appraisal Is a Hallmark of EBP

Appraising rather than accepting is what separates evidence-based practice from citing literature.

The rule everything else sits under.

EBP 0453 The Overarching Rule

Every study is read for what it can support, and no study is taken on the strength of where it appeared.

The first of three questions.

EBP 0454 Validity

Are the results of the study valid — did the methods produce a trustworthy answer.

The second.

EBP 0455 Reliability

Are the results reliable — the size and consistency of what was found.

Why they are separate.

EBP 0456 Validity and Reliability Are Independent

A study can be valid and unreliable, or reliable and invalid. They are separate properties and are asked separately.

The third, and the one about your patient.

EBP 0457 Applicability

Will the results help my patients. This is where the study meets the person in front of you.

Six videos on the structure. The first phase is the one most people mistake for the whole of appraisal, and the third is where the answer actually forms.

The structure of the whole unit.

EBP 0458 Four Phases of Critical Appraisal

Appraisal runs in four phases, and the first is the one most people mistake for the whole thing.

Phase one.

EBP 0459 Phase One — Rapid Critical Appraisal

A rapid pass asking the three questions of each study, to decide what is worth keeping.

What comes out of phase one.

EBP 0460 Keeper Studies

The studies that survive triage. Everything after this works on the keepers.

Phase two.

EBP 0461 Phase Two — Evaluation

Pulling the same elements out of every keeper into one table, so the body can be seen at once.

Phase three, and the one that is misunderstood.

EBP 0462 Phase Three — Synthesis

Synthesis weighs the studies together. It is not a vote, and the count of studies on each side is not the answer.

Phase four.

EBP 0463 Phase Four — The Recommendation

A recommendation that states what to do and how confident the body of evidence allows you to be.

Six videos on scope. Everything the search returned goes through this, including the studies that disagree with each other.

What goes through this.

EBP 0464 What Gets Appraised

Everything the search returned is appraised, not only the studies that agree with each other.

How thorough the reading is.

EBP 0465 Every Possible Flaw Is Considered

Appraisal considers every way a study could have gone wrong, then judges whether those flaws matter here.

One flaw with its own entry.

EBP 0466 Commercial Influence

Who funded the work and what interests they hold. Declared interest is not disqualifying, and undeclared interest is a problem.

The word for what you are judging.

EBP 0467 Credibility

Whether the study is believable given how it was done.

The applicability question sharpened.

EBP 0468 Direct Application to These Patients

Whether the finding applies to the patients you actually have, rather than to patients in general.

The honest case.

EBP 0469 Sometimes the Study Does Not Exist

For some questions the study has not been done. Saying so is a finding, and it is not a licence to overstate what was found.

Eleven videos on the central skill of the unit. Watch corroboration across levels, which is the strongest signal a body can give you.

The central skill of the unit.

EBP 0470 Weighing a Body of Evidence

The judgement is about the body as a whole, and the next entries are the things you weigh.

The first thing you weigh.

EBP 0471 Number of Studies

How many studies address the question. More is informative, and it does not settle anything by itself.

The second.

EBP 0472 Magnitude of Effect

How large the effect is where it was found. Unit 6 is where the numbers behind this get read properly.

The third.

EBP 0473 Consistency

Whether the studies point the same way, and where they do not, what differs between them.

The fourth, and the strongest signal.

EBP 0474 Corroboration Across Levels

When different designs reach the same conclusion, the body is stronger than any of them alone.

What all this is for.

EBP 0475 The Goal Is to Understand All We Know

The purpose is to understand everything currently known about the question, rather than to find support for a position.

A criticism the field takes seriously.

EBP 0476 The Randomised-Trials-Only Criticism

The criticism that evidence-based practice recognises only trials. The course answers it directly rather than dismissing it.

The distinction unit 1 introduced.

EBP 0477 Levels Do Not Assess Quality

A level describes the design, not how well the study was executed. This is the same point entry 0031 made.

What strength is for.

EBP 0478 Strength Determines Confidence

The strength of the body determines how confidently you can act, which is what the recommendation states.

The word for that confidence.

EBP 0479 Certainty

Certainty is how sure the body of evidence allows you to be about the effect.

How certainty is arrived at.

EBP 0480 Appraising Certainty

Certainty is appraised rather than read off a table, because it depends on consistency, magnitude and risk of bias together.

Eight videos returning to the definition from a different direction: what actually feeds a decision.

The frame for the next three.

EBP 0481 The Highest Quality Knowledge

The highest quality knowledge for a decision comes from three sources together.

The first.

EBP 0482 Source One — Valid Research Evidence

Valid research evidence, appraised rather than accepted.

The second.

EBP 0483 Source Two — Clinician Expertise

Clinician expertise, including what this setting can deliver.

The third.

EBP 0484 Source Three — Patient-Valued Preferences

What the patient values, which unit 5 takes up in full.

A wider list.

EBP 0485 Five Kinds of Evidence

Five kinds of evidence feed a decision, of which research is one.

One kind named here.

EBP 0486 Qualitative Evidence

Qualitative evidence answers meaning questions. Unit 7 is the whole of it.

And another.

EBP 0487 Mixed Methods Evidence

Mixed methods work combines both, and is more than running two studies side by side.

What all of it produces.

EBP 0488 Evidence-Based Decision Making

The decision is the output, and evidence is one input to it rather than the whole of it.

Eight videos on how the three activities feed each other, and how your own data close the cycle.

The three activities, again.

EBP 0489 Research, EBP and QI Together

Research, evidence-based practice and quality improvement, working together rather than in competition.

How they depend on each other.

EBP 0490 Each Depends on the Others

Research needs questions from practice, practice needs research to translate, and improvement needs both.

The direction people forget.

EBP 0491 Practice-Based Evidence

Evidence generated by practice itself, which is the reverse of the usual direction.

How the loop closes.

EBP 0492 Internal Evidence Closes the Loop

Your own outcome data feed the next question, which is what makes the cycle continuous rather than linear.

What the loop is for.

EBP 0493 Sustainability Is the Purpose

The purpose is practice that keeps improving, rather than a project that ends.

What you watch.

EBP 0494 Quality Indicators

Measures chosen to indicate whether quality is where it should be.

Why tracking matters.

EBP 0495 What Tracking Makes Possible

Tracking indicators over time is what lets you see a change rather than a single reading.

What you compare against.

EBP 0496 Benchmarks

A benchmark gives the comparison. Without one, a number on its own says very little.

Three videos. The first is the most consequential misconception in this unit, because acting on it means stopping after triage.

The first error.

EBP 0497 Misconception: Appraisal Is Phase One

Rapid critical appraisal is the triage pass, not the appraisal. Three phases follow it, and the synthesis is where the answer forms.

The second.

EBP 0498 Misconception: A Level Is a Verdict

A level describes a design. Quality of execution decides whether to believe this particular study.

The third.

EBP 0499 Misconception: More Evidence Is Better Evidence

Ten weak studies do not outweigh two strong ones. Weighing is not counting.

One procedure taking a body of evidence through all four phases.

The unit assembled.

EBP 0500 Critically Appraising a Body of Evidence

One body of evidence taken through all four phases to a recommendation that states its own certainty.

That is step three at the level of the body. Against the outcomes. Three questions of every study: is it valid, are the results reliable, and will it help my patients. Validity and reliability are independent — a study can be valid and unreliable, or reliable and invalid — so they are asked separately. Four phases. Rapid critical appraisal triages to keepers. Evaluation puts the keepers side by side in one table. Synthesis weighs them together. And the recommendation states what to do and how confident the evidence permits you to be. What you weigh is the number of studies, the magnitude of the effect, the consistency between them, and corroboration across levels — which is the strongest signal, because different designs reaching the same conclusion is worth more than any one of them alone. A level describes a design, not how well a study was executed. That is the same point unit 1 made at entry 0031, and it is the most repeated correction in this course. And synthesis is not a vote. Counting studies on each side is not weighing them, and where studies disagree the first question is what differed between them. Unit 5 takes up the component that appraisal cannot supply: what the patient values.