Clinical Outcome Assessments (COAs) need to have precise terminology to make sure that patients can report their symptoms accurately. What happens when languages do not have distinct terms for medical concepts that are in the source language, which is usually a variety of English? This is a common challenge in the cross-cultural adaptation of COAs. If not addressed adequately, it can lead to misinterpretation, inconsistencies in responses across sites and data that may not be reliable. This can negatively affect the data integrity of entire clinical studies.

A common linguistic challenge in COAs is the lack of distinction between “pain” and “discomfort” in many languages. However, there are similar issues distinguishing:

·       Fatigue and weakness

·       Anxiety and nervousness

·       Dizziness and vertigo

·       Depression and sadness

·       Shortness of breath and suffocation.

There are many languages where these distinctions are not clear-cut, where the semantic fields have a high degree of overlap or where there are not distinct words for these concepts. This article takes a brief look at each of these and ends by asking the question: what happens when cognitive debriefing, as a method to test the translations with patients, may not be enough to identify these ambiguities?

Pain and Discomfort

Many languages do not differentiate between “pain” (something sharp, acute and intense) and “discomfort” (something milder than “pain”, tolerable but still a nuisance). For example, in Japanese ‘itami’ can mean both concepts. In Chinese, the word ‘téng’ covers ‘pain’ but also includes ‘aches’ and ‘soreness’. Arabic and Tamil do not distinguish between the two, while in Korean ‘apeum’ applies to any kind of unpleasant situation. Not expressing this adequately in the target languages could lead to underreporting of severe pain or treating discomfort as pain. This can distort clinical data.

The solutions could be to add further descriptions. Instead of “how much pain?”, this could be expressed as “How much severe or intense pain did you feel?” Or, for a response choice, there could be an impact description, such as “moderate: pain that affects your daily activities but is manageable”. Ideally, pain should be measured along visual or numeric scales (e.g. Visual Analog Scale) to help patients judge their own pain levels accurately.

Fatigue and Weakness

Some languages do not make a difference between ‘fatigue’, which is a lack of energy that is persistent, and ‘weakness’, which is a loss of physical strength. Examples of this include ‘fatigue’ in French which can mean both ‘tiredness’ and ‘physical weakness’. In Spanish, ‘debilidad’ (weakness) and ‘fatiga’ (fatigue) overlap as concepts, while Chinese ‘píláo’ means general exhaustion, rather than clinical fatigue. The outcome of this can lead to symptoms being misclassified in chronic fatigue syndrome, neuromuscular disorders or post-viral fatigue.

A solution could be to provide the patient with a description of the symptom’s impact, such as “Fatigue: A persistent lack of energy that does not improve after resting”.  For new measures exploring tiredness and fatigue, response scales could also be function-based, as follows:

·       I do not feel any tiredness or weakness

·       I feel some tiredness but I can recover quickly

·       I feel a fatigue that makes it harder for me to do daily activities

·       I feel extremely exhausted and I am unable to move.

Developers need to design Patient-Reported Outcomes with a view to translatability of concepts from the outset.

Anxiety and Nervousness

A lot of languages do not have distinct words for ‘anxiety’, as a long-standing clinical condition, and ‘nervousness’, as a temporary emotional state. For example, in German, ‘Angst’ means both ‘fear’ and ‘anxiety’; in Russian ‘Trevoga’ means both ‘concern’ and ‘anxiety’, while, in Japanese, ‘fuan’ can translate as both unease and clinical anxiety. Getting this wrong can cause healthy patients to overreport levels of anxiety or the opposite: people with clinical anxiety can underreport the intensity of their symptoms.

When designing a new instrument with a view to cross-cultural use, developers could consider a two-step format, such as:

Step 1: In the past week, have you felt anxious or worried? (with a ‘Yes / No’ response choice).

Step 2: If you answered ‘yes’, how much did this interfere with your daily activities? (with response choices, such as not at all, a little, somewhat, a lot, completely).

Dizziness and Vertigo

Some languages, such as Spanish and French, do not distinguish between ‘dizziness’, as in lightheadedness, and ‘vertigo’, as in feeling a sensation of spinning. Meanwhile, other languages, such as Chinese, do not have a discrete word for vertigo. This can lead to a misreporting of symptoms of balance disorders.

A solution to pre-empt this kind of confusion for new outcomes assessments could be to provide a real-world context, such as: “Have you felt lightheaded, as if you were going to faint?” to convey ‘dizziness’ and “Have you felt like the room was spinning around you?”, for ‘vertigo’.

Depression and Sadness

Some languages, such as Korean, Hindi and Arabic do not distinguish between depression as in the clinical condition and general sadness. This can lead to mental health assessments that are inaccurate.

COAs that are developed in this area could solve this by clarifying clinical depression, e.g. “a persistent low mood, loss of interest and fatigue, lasting two weeks or more” and differentiate this from ‘sadness’, i.e. “A temporary emotional response to a specific event”.

Shortness of Breath and Feeling Suffocated

Some languages, such as Mandarin, Russian and Arabic do not have discrete words for ‘shortness of breath’ (i.e. dyspnea) and suffocation (the inability to breathe). The risk of this is the overreporting of severe symptoms.

In COA development, a solution to this obstacle is to use function-based categories instead of terms that could be subjective:

·       I can walk at a normal pace without needing to stop

·       I need to stop to catch my breath when I walk uphill or quickly

·       I feel out of breath even when I am resting.

Cognitive Debriefing

What happens when Cognitive Debriefing does not identify these issues? Sometimes cognitive debriefing can be deficient in terms of resolving (or even identifying) these linguistic ambiguities across languages. If this is done in the development stage, then developers can introduce other strategies, such as:

·       Proxy descriptions (sharp, intense sensation), alongside the symptom (here, pain)

·       Visual or numeric scales, so patients can categorise symptoms

·       Real-life contexts, placing the symptom in an everyday situation that as many people as possible can relate to

·       Break questions into multiple steps

·       Allow open-ended responses during the testing phases, such as concept elicitation, content validity

·       Response scales could be constructed to reflect the functional limitations, rather than subjective descriptions.

Design with the entire world in mind

One thing becomes abundantly clear: COAs need to be developed with translation in mind from the outset. A developer working in Boston or London needs to be thinking of patients in China… Tanzania… Paraguay when constructing each and every item. This means that specialist linguistic input needs to be incorporated at the earliest possible stage. It cannot be an afterthought, as is the case currently. Otherwise, response accuracy can be compromised when collecting data across cultures.

Thank you for reading,

Mark Gibson

Leeds, United Kingdom, March 2025