The concept of health-related quality of life (HRQOL) encompasses various dimensions, such as perception of health, level of independence, and interaction between a person and his or her environment.1–3 Although there is no widely accepted definition of HRQOL in the literature,4 the growing interest in this concept is undeniable. HRQOL assessment allows clinicians and researchers to evaluate the impact of disease on the well-being of patients and has become an important consideration when evaluating the outcomes of diverse medical interventions.

In the field of dermatology, concerns about aesthetic alterations, which are chronic in many cases, have led clinicians to use different tools to measure the impact of various skin diseases on their patients’ lives and their interaction with the environment.

Actinic keratosis (AK) is an incipient form of superficial squamous cell carcinoma (SCC) that typically presents as multiple lesions in areas of long-term exposure to UV radiation, generally from the sun but also from tanning devices. The condition is thus highly prevalent (affecting over 20% of individuals older than 60 years) and is associated with a risk of recurrence due to field cancerization (presence of subclinical lesions in photo-damaged skin underlying clinically evident lesions). Generally nonsurgical treatment is necessary to prevent progression to invasive forms of SCC.5 AK lesions present with varying grades of hyperkeratosis and manifest in multiple forms, ranging from slight scaling to highly adherent crusts. They frequently cause itching or a burning sensation.

Numerous scales are available to assess the impact of dermatologic conditions on QOL and they have been widely used in clinical practice and research. Examples are the Skindex-296 and the Dermatology Life Quality Index (DLQI).7 While other more specific instruments, such as the Skin Cancer Index8 (recently validated in Spanish9), are used to assess QOL in patients with nonmelanoma skin cancer, no specific questionnaires existed for AK until Esmann et al.10 developed the Actinic Keratosis Quality of Life questionnaire (AKQoL) in 2012.

Tools for evaluating QOL must, among other requirements, be understandable to the patient and this understanding is linked to sociocultural background. Most HRQOL scales, whether generic or specific to a disease and/or medical specialty, are created in English and only some have been translated and adapted for use in the Spanish population.11 When producing a new version of an HRQOL instrument, it is necessary to follow certain procedures to culturally validate the new instrument12 and ensure that it measures what it was designed to measure (validity); it must also be sufficiently reliable, i.e., offer the necessary stability, accuracy, and consistency for measuring a determined trait.13

The aim of this study was to produce a linguistically and semantically equivalent version of the AKQoL in Spanish that would constitute a specific tool for evaluating the QOL of patients with AK in our country. We also wished to evaluate the psychometric properties of the Spanish AKQoL.

The AKQoL is a self-administered questionnaire, originally created in Danish, that evaluates different situations associated with the presence of AK lesions. It consists of 9 items scored on a 4-point scale ranging from 0 (rarely/not at all) to 4 (very much/all the time). It is composed of 3 domains, or subscales: function, which covers personal views of QOL, social life, and appearance (items 1, 8, and 9); emotions, which covers feelings such as fear, guilt, shame, worry, and irritation/bother (items 2, 4, and 6), and control over life in general (items 5 and 7). It also has a single global item (item 3). The total possible score thus ranges from 0 to 27, with higher scores indicating greater impairment of QOL.

Adaptation of the AKQoL

The original Danish questionnaire was translated and culturally adapted in accordance with the methodological model for the cultural adaptation of self-administered questionnaires14 with the aim of maintaining semantic equivalence. The first step was the translation-backtranslation phase. The Danish questionnaire was translated into Spanish and the results were evaluated by a group of experts (Fig. 1). The Spanish questionnaire was then backtranslated (into Danish) by 2 native Danish translators and compared with the original. Once the preliminary version of the Spanish AKQoL had been agreed on, it was tested for understanding in a group of patients with comparable characteristics to the target population (38 elderly people with AK from the urban area of Barcelona) and then administered to a second group of volunteers without AK (people older than 18 years from the same geographic area) to evaluate test-retest reliability. The final version of the questionnaire was then administered to a third group of patients from a multicenter observational study to evaluate, among other factors, the impact of AK-related treatment on QOL.

Figure 1.

Flowchart showing process used to translate, culturally adapt, and validate the Actinic Quality of Life Questionnaire (AKQoL) in Spanish.

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All the participants who completed the questionnaire in the different phases were previously informed of the nature and objectives of the study and they all voluntarily agreed to participate and to have their data recorded. The study and study material were approved by the clinical research ethics committee at Hospital General Universitario Gregorio Marañón in Madrid, Spain.

The translation, cultural adaptation, and backtranslation phase was completed without disagreements between the evaluators. The comprehension test was performed by administering the prefinal version of the questionnaire to 38 individuals (66.7% men and 33.3% women) with a mean (SD) age of 63.7 (8.34) years. Only 1 item required clarification, and this was not related to language.

The final version of the AKQoL in Spanish was completed by 621 patients. The patients’ characteristics are summarized in Table 1.

Test-Retest Reliability

The correlation coefficient (Spearman rho) for test-retest reliability over 2 weeks was 0.932 and the Bland Altman plot of the scores from both questionnaires showed that the majority of individual differences were situated within the confidence limits of the mean (SD) difference of 0.22 (1.46) (95% CI, -2.64 to 3.08) points (Figs. 2 and 3).

Figure 2.

Bland-Altman plot showing test-retest reliability (interval of 2 wk). The continuous line shows the mean difference between the test and the retest scores and the dotted lines show the 95% limits of agreement (mean difference ±1.96SD).

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Figure 3.

English Translationa of the Final Spanish Version of the AKQoL.

aThis English version is an unvalidated translation of the Spanish AKQoL, provided only for purposes of understanding the present study.

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The use of instruments to measure QOL and different aspects of health care is essential for both research purposes and for improving understanding of patient-related factors outside strictly clinical contexts. Conditions like AK are common reasons for consultation in routine practice, evidencing their impact. These conditions are chronic, affect visible parts of the body, frequently cause symptoms, and are invariably associated with local treatment-related adverse effects of varying severity.

We have produced a validated, culturally adapted questionnaire with adequate levels of internal consistency and high specificity for AK for use among patients with this disease in our setting.

According to the data in the literature,11 the AKQoL is the first specific HRQOL tool for patients with AK to be validated and adapted for use in Spanish. Not only is it semantically, conceptually, and culturally equivalent to the original questionnaire, but it also identifies differences between patients with AK diagnosed by a dermatologist.

Because AK is an incipient disease with a risk of malignancy, numerous aspects of its impact on QOL are not typically considered in other scales and questionnaires. De Troya-Martín et al.9 recently published the Spanish version of the Skin Cancer Index for measuring the QOL of patients with cervicofacial nonmelanoma skin cancer. The Skin Cancer Index has certain similarities to the AKQoL, not just because of the pathophysiological association between the 2 conditions, but also because of their possible psychological impact. The Skin Cancer Index, however, which has adequate psychometric properties, contains items that are specific to malignant lesions (e.g., evaluation of aspects such as metastasis and the physical, occupational, and social consequences of surgery) and not generalizable to AK.

Our evaluation of the psychometric properties of the Spanish AKQoL shows sufficient homogeneity between items and between each of the scales in relation to the original questionnaire. The low correlation with the Skindex-29, which is a generic scale with good psychometric properties, suggests that the AKQoL is highly specific for AK. A previous study of the AKQoL in patients in Denmark showed negative and nonsignificant correlations between raw scores on this questionnaire and other questionnaires, such as the EQ-5D.16 In addition, the mean scores obtained for the Spanish AKQoL and the Skindex-29 show much lower floor and ceiling effects for the AKQoL. Therefore, considering our results and those reported in the literature, the Spanish version of the AKQoL can be considered a complementary tool, as it measures distinct HRQOL factors.

One limitation of our study is that it was not possible to replicate the results of the factor analysis performed by Esmann et al.10 using a Rasch model. To compensate for this limitation, we applied nonparametric Spearman correlation tests to assess correlations between domains and compared our results to those of Esmann et al.

Apart from the procedures established for the validation of the AKQol and the questionnaire scores showing that AK has an impact on patient QOL, we would like to draw attention to the fact that women scored higher on average than men, although the difference was not statistically significant. Although these comparisons were not the object of our study, they do open the door to further research focusing on different aspects of QOL in patients with AK.

The authors declare that they have no conflicts of interest.