Psychometric Evaluation of the IWQOL-Lite (Spanish Version) When Applied to a Sample of Obese Patients Awaiting Bariatric Surgery

Abstract

Background Obesity may have an impact on key aspects of health-related quality of life (HRQOL). In this context, the Impact of Weight Quality of Life (IWQOL) questionnaire was the first scale designed to assess HRQOL. The aim of the present study was twofold: to assess HRQOL in a sample of Spanish patients awaiting bariatric surgery and to determine the psychometric properties of the IWQOL-Lite and its sensitivity to detect differences in HRQOL across groups. Methods Participants were 109 obese adult patients (BMI≥ 35 kg/m 2 ) from Barcelona, to whom the following measurement instruments were applied: IWQOL-Lite, Depression Anxiety Stress Scales, Brief Symptom Inventory, and self-perception items.Results Descriptive data regarding the IWQOL-Lite scores obtained by these patients are reported. Principal components analysis revealed a five-factor model accounting for 72.05% of the total variance, with factor loadings being adequate for all items. Corrected item-total correlations were acceptable for all items. Cronbach's alpha coefficients were excellent both for the subscales (0.88-0.93) and the total scale (0.95). The relationship between the IWQOLLite and other variables supports the construct validity of the scale. Finally, sensitivity analysis revealed large effect sizes when comparing scores obtained by extreme BMI groups. Conclusions This is the first study to report the application of the IWQOL-Lite to a sample of Spanish patients awaiting bariatric surgery and to confirm that the Spanish version of the instrument has adequate psychometric properties.

Factors Associated with Health-Related Quality of Life Among Overweight and Obese Korean Women

“…Moreover, to the best of our knowledge, the present study is the first to report a significant association of BMI with total IWQOL in a multivariable-adjusted model; in particular, we reported significant associations between BMI and IWQOL scores among individuals who were mostly in the category of overweight (i.e., 76% of total participants). Although the IWQOL-Lite questionnaire is known to reflect weight-related HRQOL, most previous studies elucidated a significant relation of BMI to IWQOL among obese or morbidly obese individuals, specifically those awaiting bariatric surgery, compared to those having a normal-weight (Andrés et al 2012;de A Mariano et al 2010;Mueller et al 2011). Our study adds to the body of knowledge about how excess weight is related to quality of life of women who are only overweight.…”

“…Overweight and obese women may be particularly more vulnerable to lower HRQOL than their male counterparts. Overweight and obesity per se may have a stronger association with perceived physical impairments in HRQOL among women than among men (Andrés et al 2012). Such a gender difference in impaired HRQOL may be also attributable to psychological and social backgrounds among obese women.…”

Recommendations on the most suitable quality‐of‐life measurement instruments for bariatric and body contouring surgery: a systematic review

“…Fifteen instruments (BS) were minimally validated and are not recommended for use until adequate validation studies clarify their quality. These included Moorehead‐Ardelt Quality of Life Questionnaire (M‐A QoLQ)/Bariatric Analysis and Reporting Outcome System , GIQLI , Impact of Weight Quality of Life‐Lite (IWQoL‐Lite) , M‐A QoLQII , Post Bariatric Outcome Tool , OP‐scale , EQ‐5D‐5L , Greek, Korean, Portuguese, Czech, German, Italian and Spanish M‐A QoLQII and Spanish IWQoL‐lite . The evidence of the majority of the measurement properties of these instruments could not be interpreted due to poor methodological quality of the study.…”

“…The evidence of the majority of the measurement properties of these instruments could not be interpreted due to poor methodological quality of the study. The OP-scale showed moderate evidence for good internal consistency and structural validity (40), and the Spanish IWQoL-lite showed moderate evidence for good internal consistency and limited evidence for good structural validity (46). Limited evidence was found for good reliability of the Greek and Portuguese M-A QoLQII (48,50).…”

“…Structural validity was poor for the BQL-Index (34), and conflicting evidence was found for responsiveness of the Laval Questionnaire (33). (48)(49)(50)(51) and Spanish IWQoL-lite (46). The evidence of the majority of the measurement properties of these instruments could not be interpreted due to poor methodological quality of the study.…”