A correct text can still fail
Language assessment often concentrates on features that can be counted or classified: grammatical errors, lexical range, sentence complexity and fluency. These measures reveal important aspects of proficiency. Yet a text can contain sophisticated vocabulary and relatively accurate grammar while leaving the reader unsure what the writer wants to say. Another text may be linguistically simple and imperfect but provide exactly the information needed in a clear, usable form.
Folkert Kuiken and Ineke Vedder describe this missing dimension as functional adequacy. Their starting point is practical: second-language writing cannot be assessed fully without asking whether the production fulfils its communicative function. In 2017 they published a study proposing and testing a rating scale designed to make that functional dimension visible.
What “functional” means in this study
Functional adequacy is not a softer substitute for linguistic quality. It asks a different family of questions. Has the writer supplied relevant ideas? Has the task actually been performed? Can the reader understand the intended meaning without unreasonable effort? Do the parts form a coherent contribution rather than a sequence of disconnected sentences?
This changes the position of the reader. Instead of treating the text only as evidence of the writer’s internal language system, the scale treats it as an act addressed to someone. Meaning has to arrive. A successful text is therefore judged in relation to its purpose, requested content and effect on comprehension—not against an abstract ideal sentence alone.
Four dimensions instead of one global impression
The authors divide functional adequacy into four subscales. Content concerns the number, relevance and consistency of information units. Task requirements concern whether the writer has done what the prompt asks rather than merely produced language related to the topic. Comprehensibility concerns how readily a reader can recover the ideas and purpose. Coherence and cohesion concern the organisation and connection of those ideas across the text.
The separation matters because a single global judgement can conceal different problems. A text may be easy to understand but omit half the requested information. It may contain relevant ideas but arrange them so poorly that the reader has to reconstruct the argument. It may be coherent yet respond to a different task. Four scores create a more interpretable profile than one vague impression that the text is “good” or “weak”.
- Content: is there enough relevant and consistent information?
- Task requirements: has the communicative assignment been fulfilled?
- Comprehensibility: can the reader understand the ideas and purpose without excessive effort?
- Coherence and cohesion: do the ideas form a connected, organised text?
How the scale was tested
The study did more than propose attractive criteria. Non-expert raters used the scale to assess a corpus of argumentative texts written in Dutch and Italian by native and non-native writers. This choice was important. A scale useful only to the researchers who designed it would have limited practical value; the authors wanted to know whether people without specialist rating expertise could apply the four dimensions consistently.
Each dimension was represented by level descriptors rather than a simple yes-or-no decision. For comprehensibility, for example, the progression moves from a reader having to guess most ideas and purposes towards a text that is readily understood and highly readable. The descriptors anchor judgement in the reader’s experience and observable qualities of the text.
What the result means—and what it does not
The authors concluded that functional adequacy could be measured reliably with the four subscales. That result supports the idea that communicative success is not too vague to assess. When criteria are separated and described carefully, raters can make structured judgements about whether a second-language text works.
Reliability, however, does not make the scale universal. The study concerned particular argumentative writing tasks, particular groups of Dutch and Italian writers and a particular rating procedure. It does not show that the same descriptors can be transferred unchanged to every genre, age group or spoken interaction. Nor does functional adequacy replace measures of accuracy, complexity and fluency; it adds information that those measures do not provide.
Why this matters for everyday communication
Consider two messages to a landlord about a broken heater. The first uses impressive language but never states when the problem began, whether the apartment is currently cold or what response is requested. The second contains several grammatical errors but identifies the fault, explains its consequence and asks for a visit. Linguistic analysis may favour the first in some respects; functional assessment explains why the second may serve the real purpose better.
The example is not an argument against correctness. Errors can make a message difficult or change its meaning. The point is that correctness becomes one contributor to communicative success rather than its complete definition. A useful assessment should be able to say both that the second message worked and that particular linguistic changes could make it work more efficiently.
From functional adequacy to speech adaptation
Kuiken and Vedder studied writing, not adaptive conversation. Their paper does not propose the Functional Speech Adaptation Assessment and does not measure how a speaker reacts when an interlocutor fails to understand. The direct contribution is more foundational: it demonstrates that the outcome of language use can be broken into explicit, ratable dimensions.
FSA extends this logic cautiously. In spoken interaction, we may ask whether the purpose was achieved and the contribution remained comprehensible, but also what happened when conditions changed: did the person notice difficulty, seek feedback, reformulate or use context differently? Those additions require their own validation. The 2017 scale supplies a precedent, not ready-made proof. It shows how assessment can move from “How correct was the language?” towards “What did this person manage to accomplish with it?”
Primary source
This is the paper on which the article is based. The link leads to its DOI or scientific publisher.
- Kuiken, F., & Vedder, I. (2017). Functional adequacy in L2 writing: Towards a new rating scale.
Operationalises functional success through content, task fulfilment, comprehensibility, coherence and cohesion.
The text above is an interpretation by the Functional Speech Adaptation project; the cited authors do not necessarily use this term or framework.