Study Validates Thai Version of Angioedema Quality of Life Questionnaire

A Thai version of the Angioedema Quality of Life (AE-QoL) questionnaire is a reliable way to measure health-related quality of life in Asian people with recurrent angioedema, a new study demonstrates.

The study, “Angioedema quality of life questionnaire (AE-QoL) – interpretability and sensitivity to change,” was published in Health and Quality of Life Outcomes.

Measuring health-related quality of life for people with chronic conditions is important in both research and clinical practice, and it is typically done with questionnaires. The AE-QoL is one such questionnaire specific to angioedema. (There also is a version modified specifically for hereditary angioedema.)

The AE-QoL consists of questions that are scored from 1-5, with higher scores indicating a greater detrimental impact on quality of life for the particular area assessed. The cumulative score is then scaled from 0–100, with 0 representing no impact on quality of life and 100 indicating the greatest possible impact.

The AE-QoL was developed originally in Germany, and it has since been adapted in 29 languages and applied in 25 different countries. However, it had not yet been translated into Thai; moreover, according to the researchers who authored the new study, it has never been validated anywhere in Asia.

In the new study, researchers created a version of the AE-QoL in Thai. Then, they had 86 people with recurrent angioedema (age range 18–76 years) complete the questionnaire on two separate occasions.

For comparison, the participants also completed two other quality of life-related questionnaires: the dermatology life quality index (DLQI) and the patient global assessment of quality of life (PGA-QoL). As the names of these questionnaires suggest, neither is specific to angioedema. However, Thai versions of both of these questionnaires have been validated in previous studies, so they serve as a reasonable metric for judging the validity of the new assessment.

Scores on the AE-QoL showed strong and statistically significant correlations with both the PGA-QoL and the DLQI. Furthermore, scores from both times the assessment was taken were generally similar, suggesting that the questionnaire is reliable.

The researchers also demonstrated, using statistical models and the scores from PGA-QoL and DLQI, that participants could be classified as “no effect” on quality of life (scores of 23 or less), “small effect” on quality of life (scores of 24–38), or “moderate to large” effect on quality of life (scores of 39 or more).

The researchers noted that, in their sample, they were not able to significantly distinguish “moderate” from “large.” However, they suggested that this probably is due to the relatively few participants in their sample who had very high scores, speculating that further studies with more severely affected participants might allow such distinctions to be made.

The statistical models also suggested that a change in score of seven points or more would be clinically meaningful — that is, indicative of a change in quality of life that the person taking the questionnaire would actually notice  day-to-day.

“The Thai version of AE-QoL was found to be a valid and reliable instrument for assessing disease-specific impact on QoL in Thai [recurrent angioedema] patients,” the researchers concluded, noting that this study “is the first to validate the AE-QoL in Asia.”