IKDC

For Medical Students

What It Tests

The IKDC is a patient completed questionnaire about knee symptoms, function and sporting activity, so it records what the patient reports rather than what the examiner finds. 4.22.8 covers the use of these scores.

It was designed to work across different knee problems, which is what separates it from the condition specific instruments. 4.22.3 covers the Lysholm score.

It matters because the examination and the questionnaire answer different questions, and a treatment decision usually needs both. 4.18.6 covers functional limitation.

How It Is Performed

Give the questionnaire to the patient to complete themselves, since a clinician reading it aloud changes the answers.

Give it before the consultation rather than during it, so the answers are not shaped by the discussion.

Explain the recall period the questions ask about, because patients otherwise answer about today.

Check for missing items before scoring, since an incomplete questionnaire cannot be scored.

Score it with the published scoring method rather than by impression. 4.1.8 covers examination documentation.

Record the score with its date, because the value of these instruments is the comparison over time.

Record the examination findings separately, so the two are not blended. 4.1.8 covers examination documentation.

What a Positive Means

A score is a position on a scale rather than a diagnosis, so it is read against the same patient's previous score.

A change over time is the informative result, and a single score tells you little on its own. 4.22.8 covers the use of these scores.

A low score with a normal examination means the patient's experience is worse than the findings, which is a real result rather than an error. 4.2.10 covers severity.

A high score with abnormal findings means the patient is coping, which changes the treatment threshold. 4.18.6 covers functional limitation.

An incomplete questionnaire is unscored rather than estimated.

No item count, score range or validation figure appears on this page. Those are properties of a published instrument and stating one from memory is the same class of claim as an invented citation, so the page describes what the instrument does and a reviewer with the questionnaire can add the numbers.

MRCS Level

How It Is Performed

In a viva this is the outcome measure question and the expected answer separates patient reported from clinician assessed.

The expected points are the self completion, the timing, the recall period, the completeness check, the published scoring, the dated record and the separate examination record.

Say that the patient completes it themselves, and give the reason. 4.22.8 covers the use of these scores.

Say that the score is compared with the same patient's earlier score rather than with a population value. 4.1.8 covers examination documentation.

Say that a questionnaire does not replace the examination. 4.1.4 covers the structured approach.

What a Positive Means

The reasoning expected is that a patient reported measure captures the parts of the problem the examination cannot reach, which are the symptom burden and the effect on life. 4.18.6 covers functional limitation.

A knee specific instrument detects change in knee problems better than a general health one, which is why it is used here. 4.22.5 covers the Oxford Knee Score.

A general instrument detects change across conditions, which is the trade off the instrument's design makes. 4.22.2 covers the KOOS.

Scores are ordinal constructions, so the distance between two values is not a physical quantity. 4.22.8 covers the use of these scores.

How Good It Is

The instrument is reproducible for the same patient over time, which is what it is for.

Its best contribution is making the patient's experience recordable and comparable, which no examination finding does. 4.1.8 covers examination documentation.

It does not localise, diagnose or grade a structure.

No imaging and no examination substitutes for it, and it substitutes for neither. 4.1.6 covers that relationship.

No figures appear for any accuracy comparison on this page, under decision 023, and the comparison is the claim being made.

No item count, score range or validation figure appears on this page. Those are properties of a published instrument and stating one from memory is the same class of claim as an invented citation, so the page describes what the instrument does and a reviewer with the questionnaire can add the numbers.

FRCS Level

How Good It Is

At decision level these instruments contribute to monitoring, to audit and to research rather than to a single patient's diagnosis.

A documented score before and after treatment is the evidence of the result, and a clinical impression is not. 4.22.8 covers the use of these scores.

A score that does not improve after a technically successful operation is a finding that needs explaining rather than discounting. 4.20.1 covers the reconstruction assessment.

A score used for a population it was not designed for produces values that are not comparable with the published ones. 4.23.2 covers the elite athlete.

The choice of instrument follows the question being asked, so a sporting population and an arthritic one need different ones. 4.22.5 covers the Oxford Knee Score.

Where It Misleads

The commonest error is treating a score as a measurement of the knee rather than a report about the patient. 4.2.10 covers severity.

A single score is interpreted without a baseline, which removes the comparison the instrument is built for.

A clinician completes the questionnaire on the patient's behalf, which changes what is being measured.

Scores are compared across different instruments as if they were the same scale. 4.22.2 covers the KOOS.

A ceiling in a sporting population makes the instrument insensitive to the change that matters to them. 4.22.4 covers the Tegner scale.

Fellowship Level

Where It Misleads

At fellowship level the question is what a score supports, and the honest answer is narrower than its use.

An instrument is validated for a population and a purpose, and using it outside those is an extrapolation whose size is not knowable from the score. 4.22.8 covers the use of these scores.

Scores aggregate different domains into one number, so two patients with the same score can have different problems. 4.18.6 covers functional limitation.

Minimal clinically important differences are published quantities this repository does not state, so a change here is described rather than interpreted against a threshold. 4.2.10 covers severity.

Expectation shapes the reported score as much as the knee does, which puts the most influential variable outside the instrument. 4.22.8 covers the use of these scores.

Ceiling and floor effects truncate exactly the populations in which the decision is hardest. 4.22.4 covers the Tegner scale.

No item count, score range or validation figure appears on this page. Those are properties of a published instrument and stating one from memory is the same class of claim as an invented citation, so the page describes what the instrument does and a reviewer with the questionnaire can add the numbers.