Translatability assessment is not optional: it is where linguistic validation actually begins

Through the Linguistic Validation Lens – Part 2

In many workflows, linguistic validation is treated as something that starts once the source text is finalized.

Translation begins. Back translation follows. Cognitive debriefing is scheduled.

But by that point, an important question is often overlooked:

What if the source text was never truly ready to travel across languages in the first place?

This is where translatability assessment (TA) comes in, not as a formality, but as the first real step in ensuring that an instrument can function across languages and cultures.

What translatability assessment is really for

Translatability assessment is sometimes reduced to a simple idea: identifying “difficult-to-translate” wording. In practice, it goes much deeper than that.

It is a structured review of the source instrument (title, instructions, items, response choices) with one central question in mind:

Will this concept hold together when it moves across languages?

This means looking beyond vocabulary and into:

• Conceptual clarity

• Cultural neutrality

• Structural dependencies on the source language (i.e., wording, structure, or logic that only works naturally because of how the source language is built)

• Stability of response options

The goal is not to make the text easier to translate.

The goal is to make it more stable across languages, so that what is being measured remains consistent.

What happens when translatability assessment is skipped

When translatability assessment is treated as optional (or bypassed entirely) the risks are rarely visible at first.

Translations may read well. Back translations may appear acceptable. But underneath that surface, subtle issues begin to accumulate:

• Concepts that shift slightly from one language to another

• Wordings that require interpretation rather than direct transfer

• Response scales that don’t behave consistently

At this stage, everything can still look “good enough”… until cognitive debriefing begins.

Where unresolved issues resurface: cognitive debriefing as a stress test

One of the most consistent patterns in linguistic validation is this:

Issues that are not addressed during translatability assessment tend to reappear during cognitive debriefing—only amplified.

What was once a theoretical concern becomes observable:

• Participants hesitate or ask for clarification

• Paraphrased meanings drift away from the intended concept

• Interviewers need to probe more than expected

• Responses become inconsistent across participants

At that point, the issue is no longer linguistic. It becomes a measurement problem. And most importantly, it is much harder to fix.

By the time cognitive debriefing is underway, the source text is often considered final. Multiple language versions may already exist. Any change risks introducing inconsistencies across versions that are already in progress.

In other words, the same issue that could have been resolved early, at the source level, now requires downstream adjustments that are more complex, more costly, and less effective.

Cognitive debriefing does not create problems. It reveals the ones that were already there.

What translatability assessment looks like in practice

A strong translatability assessment is not just a list of comments, it is an opportunity to strengthen the source.

In practice, this involves:

• Reviewing instructions, items, and response scales

• Identifying ambiguities and implicit assumptions

• Flagging cultural references or phrasing

• Detecting where grammar carries meaning in ways that may not transfer

Essentially, translatability assessment should lead to actionable source revisions, not just observations. This is where its value lies. Most often, the steps involved in the assessment of translatability are:

• Preparing the source instrument (itemizing each element and possibly incorporating the respective concept definition, if not already provided).

Effective translatability assessment depends not only on the wording of the source instrument, but also on a clear understanding of the concepts each item is intended to capture. For this reason, concept definitions are often prepared or reviewed as part of the translatability assessment workflow, even if they are not formally considered a translatability assessment step in themselves.

Note: in modern COA development, translatability assessments are often conducted from a multilingual perspective rather than on a per-target-language basis. The rationale is that TA is intended to identify source-text features that are likely to create problems across multiple languages and cultures before translation begins.

• Reviewing the source text for problem areas (most typically ambiguity; culture-specific concepts; conceptual overlap between response choices; grammatical constraints across languages; excessive linguistic complexity; construct instability (i.e., wording that risks shifting the underlying construct when translated); register appropriateness; formatting or structural issues; terms lacking direct equivalence).

  
  

• Rating the degree of difficulty involved in translating each source element according to a predefined scale, such as 0=No difficulty; 1=Minor difficulty;  2=Moderate difficulty; 3=Considerable difficulty; 4=Great difficulty; and 5=Impossible to translate or to replace with an equivalent term or expression).

  
  

• Reporting, including providing suggestions and recommendations.

The general process described above is based primarily on the ISOQOL TCA-SIG publication Emerging good practices for Translatability Assessment (TA) of Patient-Reported Outcome (PRO) measures (Acquadro et al.), while also reflecting common industry practice and my own experience working with COA instruments.

Translatability assessment and construct preservation

At its core, translatability assessment is not about language—it is about meaning. More specifically, it is about preserving the construct that the instrument is designed to measure.

A source text can be linguistically well-written and still fail to support equivalence across languages.

This is why it is helpful to distinguish between:

• Language quality (how well the text reads in the source language)

and

• Equivalence quality (how well the underlying concept survives across languages)

Translatability assessment is definitely in the second area.

It is one of the earliest opportunities to protect the validity of what is being measured, not just how it is expressed. It moves problem-solving upstream, where it is still efficient, coherent, and aligned across all languages.

A final thought

Translatability assessment is sometimes seen as something that slows projects down.

In reality, it does the opposite: it prevents avoidable complications later, when changes are harder to implement and more disruptive.

If we care about the integrity of multilingual instruments, translatability assessment is not an extra-step. It is where equivalence begins. And ultimately, it is where we decide whether our instruments are not only well written but truly ready to travel.

In this Through the Linguistic Validation Lens series, we will continue exploring key aspects of COA translation and the linguistic validation process.

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This post was written by Nora Torres, who specializes in medical translations from English to Spanish (LATAM).