Study design
This Cross-sectional translation and psychometric evaluation of the Persian version of Lupus Erythematosus Quality of Life Questionnaire (LEQoL) was conducted in 2021 at the Department of Clinical psychology, Kermanshah University of Medical Sciences (KUMS). Permission was obtained from Giménez-Espert (corresponding author of the original version of scale).
Study population
A cross-sectional study was done with a convenience sample. Participants included 172 patients with LE from Iran. From these 172 patients, 165 patients met the inclusion criteria for the study: diagnosed as systemic or cutaneous/discoid lupus erythematosus, and motivated to take participating in research” were included. All 165 patients were over 18 years old and signed an informed consent form. The data collection process occurred in March to April 2021.
Linguistic validation
The linguistic validation of the LEQoL from Spanish to Persian consisted of three steps: a forward translation, a backward translation, and cognitive interviews. Two independent, bilingual Persian-native speakers with medical backgrounds (psychologists) translated the original Spanish version into Persian. A consensus version was developed by discussion and revision of the translated versions by the authors. Backward translation of the consensus version was performed independently by one Spanish native speaker without a psychological background, who was familiar with the culture of the Spanish and translated language. Adequacy of the translated version was proven by comparison of the original with the backward-translated versions. Next, the patient examination was conducted. The personal interviews were conducted during which the interviewer asked whether the participant had any trouble in understanding the LEQoL and checked the participant’s interpretation of all items. Finally, proofreading was performed(15, 16).
Procedures
Initially a battery of tests including the Persian version of LEQoL, Symptom Checklist-90-R (SCL-90), and 36-Item Short Form Survey (SF-36). These tools were used to check validity.Then a Google Form containing all the mentioned questionnaires was created. Then a public announcement was spread to the Iranian population through the social networks Instagram and Telegram. Due to the low prevalence of LE, the notice asked individuals to call or send a message or send information or notifications if they have or know a person with lupus. The corresponding author of the article also referred to rheumatology clinics in Tehran (the capital of Iran, the most populous city in Iran) and asked clients to participate in this study. Finally, people with lupus were interviewed for 20 minutes. Regarding inclusion criteria, 165 people were included in the study. Then, the tools were provided to these people online and they were asked to send them to the researchers as soon as they completed them. The information will be collected confidentially and anonymously and the results will not be shared with others.
Instrument
Quality of Life of Patients with Lupus Erythematosus Instrument” (LEQoL): This scale consist of 21 items in five subscales: Physical Factor, Appearance factor, Emotional factors, Cognition factor, and Relationship factor. Results showed that original version of LEQoL has suitable psychometric properties(14). The higher scores indicate higher impairments in patients with Lupus. In this research we tried to assess psychometric properties of the Persian version of LEQoL.
Psychological symptoms: To evaluate the psychological symptoms of the patients, the SCL-90-R (Symptom Checklist-90-R) was utilized. The SCL-90-R evaluates the current level of the symptoms which occur during the last seven days. The aim of this scale is to carry out a brief evaluation of the type and severity of the patient's symptoms by self-assessment and has eight subscales, besides a total score (Sleeping Problems, Sensitivity, Anxiety, Depression, Obsessive-Compulsive, Somatization, Agoraphobia, and Hostility). We used the Persian manual for examining the SCL-90 data. Item scores range from zero (none) to four (severe). Cronbach's alpha's for the Iranian SCL-90 was 0.90(17).
General Quality of Life: For assessing the general quality of life in participants we used 36 Items Short Form Survey (SF-36). This scale consists of 36 items classified into eight subscales: role impairment due to physical health/role physical (4 items), mental health (5 items), energy and fatigue/vitality (4 questions), physical functioning (10 questions), social functioning (2 questions), general health (5 questions), body pain (2 items), and role impairment due to emotional health/role emotional (3 items). Two other general subscales are obtained by combining the subscales known as Mental Component Summary (MCS), and Physical Component Summary (PCS). In this scale, high scores described as higher levels of QoL, and vice versa. Psychometric researches showed that the Persian version of SF-36 has suitable validity and reliability in the Iranian population(18).
Statistical analysis
Data have been analyzed by SPSS V.25 and AMOS 26 software’s. In order to analyze the data using descriptive statistics (mean, standard deviation, frequency and percentage) as well as Cronbach's alpha method to assess internal consistency, the correlation of LEQoL with SF-36 and SCL-90 were used to assess convergent validity. Also, test-retest reliability (from 25 participants) with two week was assessed by intraclass correlation coefficient (ICC). Confirmatory factor analysis (CFA) was used to examine the adequacy of the resulting factor model. To assess model fit, this research utilized a range of incremental and absolute model fit indices, including the ratio of chi-square to degrees of freedom (X2/df), root mean square error of approximation (RMSEA),comparative fit index (CFI), The goodness of fit index (GFI), and S-Bχ2 (df). Exploratory factor analysis (EFA) was applied to examine instrument dimensionality. Kaiser-Meyer Olkin measure of sampling adequacy (KMO) and Bartlett’s test of sphericity were analyzed first to determine the suitability of the data to undergo factor analysis.