Third Step: Write clinical cases

At this point, write the content of each clinical case.

Put into context

After selecting the objectives and the fields of the assessment, it is now time to choose clinical situations representative of the reasoning problems often encountered in the discipline.

Each vignette will bring about several items. In fact, if there was only one item per vignette, it would be fastidious for the examinees to get absorbed in a long series of clinical cases. Researches indicate that the best would be 3 items per vignette.

Writing the vignette

Reproduce an authentic clinical context, by writing a scenario that describes a problematical situation capable of being encountered in daily practice

The situation described has to be:

• Problematical, even for an expert (incomplete clinical data, or conflicting data, etc.);
• Appropriate for the level of the examinees;
• Indispensable and essential to understand the question and place the candidate in a specific clinical context (otherwise, the question is not a SCT anymore).

Example (clinical case of fall; the candidate will be questioned about the diagnosis)::

A woman of 82 years old is admitted to the hospital because she fell at her residence, while she was getting up from her bed, on the morning. She could not help up and the nurse found her lying down on the floor, beside the bed, several hours after the fall. It is a matter of the third time that this old woman falls, during the last month. She has known arterial hypertension, aortic murmur, cardiac insufficiency; she receives a conversion-enzyme inhibitor, a diuretic and a tricyclic antidepressor to treat sad affect since two months. She is on a waiting list for cataract surgery. She has diet-only diabetes.

Writing the items

Start with a situation that you, clinician experts, would settle to yourselves, in order to progress towards the solution..

• Which hypotheses (options) are relevant (diagnosis, therapeutic management.) in this clinical situation?
• Each item that is linked to the vignette will connect:
  • One clinical data (such as a physical sign, complementary information, a pre-existing condition, an imaging study or a laboratory test result) that could be sought out for,
  • To one relevant option (diagnosis, investigation, treatment), in order to consider the effect that the clinical data has on it. The effect can be positive (+), negative (-) or neutral (0). The option is therefore confirmed, invalidated or unchanged.

NB:

• All the questions must be formulated in a compatible manner with the usual way of reasoning within the discipline.
• The options must be relevant as regards to the clinical case, according to the experts opinion and the knowledge field being assessed (e.g. diagnosis, management.).
• For each clinical situation, never more than 3 or 4 relevant options should be considered because research about the clinical reasoning showed that the clinicians rarely consider more than this number of options simultaneously.
• The items of an evaluation unit, in a certain field (diagnosis, management.), must be chosen in step with the elements that are the most relevant to test the ability of the candidate to mobilize his knowledge networks and to take a clinical decision. At this point of the construction of the SCT, the chosen items are those that normally give a fairly equal representation of each value of the Likert scale (e.g. -2, -1, 0, +1, +2). Each item must be independent in relation to the vignette.

Example of items (same clinical case seen before). The candidate will be questioned about the diagnosis:

Redaction of the Likert scale

The Likert scale allows the candidate to give answers to the SCT by offering a certain numbers of possible values (usually 5, numerical or alphabetic) on a graduated scale. The significance of each one of these values is given by the Likert scale anchor descriptors. For example, in this 5-anchor Likert-type scale, « -2 » signifies « the new finding makes the option very unlikely to be true » : -2, -1, 0, +1, +2

How many anchors should SCT Likert scales have? Theoretically, a scale should be as wide as possible to collect as much information as possible, but at a certain point, examinees no longer know for sure if they should provide such and such an answer, and this produces noise rather than information in measurement. Initial SCT studies were composed of seven-anchor Likert scales. It quickly became evident that this was not beneficial, and five-anchor scales are now generally used in assessment situations. Continuing medical education, where SCT is used as a learning stimulus, is an exception. In this setting, participants are asked to complete an SCT individually, discuss with other participants in small groups to reach a common answer, then to compare that answer with those of experts, to initiate the learning process. In this situation, it appears that using three-anchor scales is more effective at inducing educationally relevant discussions.

Be sure that:

• The structure of the scale is the same for the whole test with, for instance, a five-anchor scale, with negative values on the left, 0 in the neutral position and positive values on the right.
• The significance of the « 0 » is clear. For instance, neutral anchor descriptor for the diagnosis format « neutral effect of the new finding on the status of the option (hypothesis would become neither likely nor unlikely) » or, for the investigation format (utility issue) « the relevancy of the investigation option is neither more nor less useful following new information availability
• The significance of each value of the scale (alphabetic or numerical) should be adapted to the field of knowledge that is being assessed. For instance « -2 » could either signify « the hypothesis become very unlikely » or « this new information would make the investigation strongly contraindicated », according to the clinical case that focuses on diagnosis or investigation.

Example (clinical case of fall; the candidate will be questioned about the diagnosis):

The effect of the new information on the hypothesis is:

• -2: the hypothesis becomes very unlikely
• -1: the hypothesis becomes unlikely
• 0: the hypothesis is neither likely nor unlikely following the new information availability
• +1: the hypothesis becomes more likely
• +2: the hypothesis becomes very likely

When all the clinical cases have been written, gather together all the material and build up the SCT by following the instructions described in step 4.