An iconic language for the graphical representation of medical concepts

Abstract

Background: Many medication errors are encountered in drug prescriptions, which would not occur if practitioners could remember the drug properties. They can refer to drug monographs to find these properties, however drug monographs are long and tedious to read during consultation. We propose a two-step approach for facilitating access to drug monographs. The first step, presented here, is the design of a graphical language, called VCM.

Methods: The VCM graphical language was designed using a small number of graphical primitives and combinatory rules. VCM was evaluated over 11 volunteer general practitioners to assess if the language is easy to learn, to understand and to use. Evaluators were asked to register their VCM training time, to indicate the meaning of VCM icons and sentences, and to answer clinical questions related to randomly generated drug monograph-like documents, supplied in text or VCM format.

Results: VCM can represent the various signs, diseases, physiological states, life habits, drugs and tests described in drug monographs. Grammatical rules make it possible to generate many icons by combining a small number of primitives and reusing simple icons to build more complex ones. Icons can be organized into simple sentences to express drug recommendations. Evaluation showed that VCM was learnt in 2 to 7 hours, that physicians understood 89% of the tested VCM icons, and that they answered correctly to 94% of questions using VCM (versus 88% using text, p = 0.003) and 1.8 times faster (p < 0.001).

Conclusion: VCM can be learnt in a few hours and appears to be easy to read. It can now be used in a second step: the design of graphical interfaces facilitating access to drug monographs. It could also be used for broader applications, including the design of interfaces for consulting other types of medical document or medical data, or, very simply, to enrich medical texts.

Figure 1

Examples of VCM icons created by combining central pictograms, external shapes, colors and top-right pictograms. Simple physiological or pathological states are represented by combining a color that indicates the moment at which the patient state occurs, a shape that distinguishes pathological (square) and physiological (circle) states, and a central pictogram. These icons can be reused for building drug and test icons.

Figure 2

Examples of VCM disease or sign icons. Icon (a) simply indicates the anatomical and functional location of the disease. Icon (b) provides additional information about the general pathological mechanism, using a shape modifier, and icon (c) provides additional information about the function involved, by modifying the central pictogram. Icon (d) combines both the shape modifier and the pictogram modification.

Figure 3

Examples of VCM disease icons using various shape modifiers. In icon (a) a pathological agent entering in the square from the left represents the etiology, in (b) the cell in division on the left represents a tumor process, in (c) the flames at the top of the icon represent inflammation, in (d) the bleeding on the right represents hemorrhage, and in (e) the "explosion" represents pain.

Figure 4

Examples of the reuse of disease icons for building drug icons. Icon (a) does not indicate the route of administration, whereas icons (b) and (c) do.

Figure 5

The pattern used for VCM sentences, and two examples of sentences. The first example means "if patient suffers from some cardiac diseases, then this drug is contraindicated (Contraindicated for some cardiac diseases)". The second means "if the patient is aged, then the physician should prescribe biological tests to monitor renal disease risks (For elderly patients, creatinine clearance tests should be prescribed)".

Figure 6

Screenshots of the evaluation software (extracts). The two screenshots show the same document, expressed in text at the top, and VCM at the bottom.

Figure 7

Average response time for questions answered using documents in text or VCM format.