RESUMEN
BACKGROUND: Given the increase in the prevalence of overweight and obesity worldwide, the number of digital weight loss interventions has also risen. However, these interventions often lack theoretical background and data on long-term effectiveness. The consideration of individual and gender differences in weight-related psychological parameters might enhance the efficacy and sustainability of mobile-based weight loss interventions. OBJECTIVE: This paper presented an introduction to and the process evaluation of a 12-week gender-sensitive mobile health (mHealth) weight loss intervention (I-GENDO) combining computer-based and self-tailoring features. METHODS: Between August 2020 and August 2021, individuals with overweight (BMI 25.0-29.9 kg/m²), those with obesity class I (BMI 30.0-34.9 kg/m²), and those with obesity class II (BMI 35.0-39.9 kg/m²) were recruited to the I-GENDO project, a multicenter study in Germany. The mHealth intervention aimed at targeting individual psychological factors associated with the development and persistence of overweight and obesity (eg, emotional eating) using computer-based tailoring. Moreover, the intervention took a gender-sensitive approach by implementing self-tailoring of gender-targeted module versions. The computer-based assignment of the main modules, self-selection of gender-targeted module versions, and use patterns were evaluated while considering gender. Moreover, gender differences in the usability assessment were analyzed. RESULTS: Data from the intervention arm of the study were processed. A total of 116 individuals with overweight and obesity (77/116, 66.4% women; age mean 47.28, SD 11.66 years; BMI mean 33.58, SD 3.79 kg/m2) were included in the analyses. Overall, the compliance (90/109, 82.6%) and satisfaction with the app (mean 86% approval) were high and comparable with those of other mobile weight loss interventions. The usability of the intervention was rated with 71% (5.0/7.0 points) satisfaction. More women obtained the main module that focused on emotion regulation skills. Most men and women selected women-targeted versions of the main modules. Women used the app more frequently and longer than men. However, women and men did not differ in the progress of use patterns throughout the intervention. CONCLUSIONS: We developed a tailored gender-sensitive mHealth weight loss intervention. The usability of and engagement with the intervention were satisfactory, and the overall satisfaction with the intervention was also high. Gender differences must be considered in the evaluation of the effectiveness and sustainability of the intervention.
RESUMEN
BACKGROUND: Current treatments of obesity often fail to consider gender and psychological aspects, which are essential for weight loss and weight maintenance. The aim of our study was to analyze subjective illness representations (SIRs) of adults with obesity according to the Common-Sense Self-Regulation Model (CSM) by assessing their associations with weight-related variables and gender. METHODS: Data was collected via online self-assessment between April 2017 and March 2018. SIRs were operationalized by the revised Illness Perception Questionnaire (IPQ-R) and illness outcomes according to the CSM were defined as BMI, eating behaviour, physical wellbeing, bodyweight satisfaction, and shape concerns. The sample consisted of 427 adults (M = 42.2 years, SD = 10.9; 82% female) with obesity (BMI: M = 42.3 kg/m2, SD = 9.0). Student's t-tests and multiple hierarchical regression analyses were conducted with the control variables (age and BMI) and subjective illness representations and gender as independent variables. RESULTS: The explanation of outcome variances was moderate to high (21-43%) except for restraint eating behaviour (10%). Subjective illness representations showed several significant associations with weight-related variables, especially timeline and emotional representations. Female gender was significantly associated with more restraint eating behaviour [F (1, 400) = 4.19, p < 0.001] and females had unfavourable values of the weight-related variables as well as a more cyclic [t (425) = 3.68, p < 0.001], and more emotional representation [t (100) = 5.17, p < 0.001] of their obesity. CONCLUSION: The results of this study indicate that gender and subjective illness representations, especially the emotional representation, play an important role for weight-related variables. Therefore, the assessment of SIRs may constitute an economic tool to identify specific individual deficits of self-regulation.
