This study explored perceptions of meaningful weight-loss and the level of change on two patient-reported outcome (PRO) measures, the 36-item Short Form Health Survey® [SF-36v2®] and Impact of Weight on Quality of Life Lite-Clinical Trials© [IWQOL-Lite-CT©], that individuals living with overweight or obesity consider to be meaningful and indicative of treatment success. Thirty-three qualitative interviews were conducted in the US with adults living with overweight or obesity. Concept elicitation explored perceptions of minimally important/meaningful weight-loss using open-ended questions. Cognitive debriefing was used to understand thresholds for meaningful change on both measures. Most participants (n = 23/33) expected a 5% total body weight-loss to yield some benefit in physical functioning, while all participants expected a 10% weight-loss to provide a meaningful and noticeable improvement in their physical functioning. Participants indicated that an item-level 1-point score change on each measure would represent a noticeable improvement in physical functioning and indicate treatment success. Participants expected moderate weight-losses to be noticeable, with ≥ 10% weight-loss yielding the most consistent results. The findings suggested that both measures provide strong opportunity to demonstrate treatment benefit in relation to physical functioning as a small change on the response scale would represent a noticeable improvement in participants’ daily lives.
Purpose This study explored perceptions of meaningful weight-loss and the level of change on two patient-reported outcome (PRO) measures, the 36-item Short Form Health Survey® [SF-36v2®] and Impact of Weight on Quality of Life Lite-Clinical Trials © [IWQOL-Lite-CT © ], that individuals living with overweight or obesity consider to be meaningful and indicative of treatment success. Methods Thirty-three qualitative interviews were conducted in the US with adults living with overweight or obesity. Concept elicitation explored perceptions of minimally important/meaningful weight-loss using open-ended questions. Cognitive debriefing was used to understand thresholds for meaningful change on both measures. Results Most participants (n=23/33) expected a 5% total body weight-loss to yield some benefit in physical functioning, while all participants expected a 10% weight-loss to provide a meaningful and noticeable improvement in their physical functioning. Participants indicated that an item-level 1-point score change on each measure would represent a noticeable improvement in physical functioning and indicate treatment success. Conclusions Participants expected moderate weight losses to be noticeable, with ≥10% weight-loss yielding the most consistent results. The findings suggested that both measures provide strong opportunity to demonstrate treatment benefit in relation to physical functioning as a small change on the response scale would represent a noticeable improvement in participants’ daily lives.
Abstract Background. Obesity is a chronic disease with a significant negative impact on health-related quality of life (HRQoL) and specifically, physical functioning, including the ability to complete activities of daily living (ADLs). Weight loss based on lifestyle management (e.g. diet, exercise), surgery, and pharmacotherapy can improve physical functioning; however, there is a need for further qualitative research to support the content validity of patient-reported outcome (PRO) measures for use in clinical studies of obesity and thus inform regulatory decision-making. Objective. To explore the impacts of obesity on physical functioning and develop a conceptual model (a visual representation of the concepts of importance and relevance to the experience of living with obesity) to ultimately support the content validity of PRO measures.Methods. Qualitative semi-structured interviews were conducted in the United States with individuals who have overweight and obesity (Body Mass Index [BMI] ≥ 27.0 kg/m2) with a history of at least one unsuccessful dietary effort to lose body weight. Recruitment quotas targeted a sample with diverse demographic and clinical characteristics, including participants with and without diabetes. Experienced qualitative interviewers used open-ended questions to elicit spontaneous reports of the impact of obesity on individuals’ daily lives, and specific probing questions to explore impacts on physical functioning. Interviews were audio-recorded, transcribed and analyzed using thematic techniques. Results. A total of 33 participants were interviewed (mean BMI of 37.6 kg/m2 [27.4 kg/m2 to 56.6 kg/m2]; mean age of 45 years [19 to 81 years]). The sample included a mix of races (Caucasian: n=12, 36%), education completed (high school: n=17, 51%) and split of gender (female: n=16, 48%). During development of the conceptual model, two separate domains were identified to group the reported impacts on physical functioning: ‘Mobility/Movement’ and ‘ADLs’. The most frequently reported impacts related to Mobility/Movement were ‘running’ (n=31/33, 94%), ‘bending’ (n=27/33, 82%), ‘walking’ (n=26/33, 79%), ‘difficulty standing for prolonged periods’ (n=22/33, 67%), and ‘lifting’ (n=19/33, 58%). All participants reported effects on some aspect of physical functioning, which were often characterized in terms of their direct impact on ADLs such as ‘household chores’ (n=21/33, 64%). Conclusions. The conceptual model will serve as a basis to identify fit-for-purpose PRO measures with strong content validity to evaluate the impact of anti-obesity therapies on physical functioning in future clinical studies. Obesity has a consistent and significant impact on physical functioning, leading to limitations in various aspects of mobility and affecting an individual’s ability to carry out specific daily activities.
Background: Obesity is a chronic disease with significant impacts on health-related quality of life (HRQoL) specifically physical functioning (PF), which is increasingly assessed using PRO measures in clinical trials. A review of existing literature suggested that further qualitative research was required to establish patient-perceived clinically important change (CIC) thresholds for two PRO measures used in obesity studies: the acute 36-item Short Form Health Survey (SF-36v2) and Impact of Weight on Quality of Life-Lite-Clinical Trials Version (IWQOL-Lite-CT). Objective: To explore the level of change on the SF-36v2 (acute) and IWQOL-Lite-CT that individuals living with obesity consider to be meaningful, noticeable and indicative of treatment success. Methods: Semi-structured interviews were conducted in the U.S. with adults who have overweight or obesity (Body Mass Index [BMI] ≥ 27 kg/m2). Open-ended concept elicitation (CE) questions allowed participants to discuss the amount of body weight loss needed to have a noticeable improvement on PF. Cognitive tasks were later used during cognitive debriefing (CD) to explore what participants considered a CIC on each PRO measure. Results: A total of 33 participants were interviewed (mean BMI: 37.6 kg/m2 [27.4 to 56.6 kg/m2] mean age: 45 years [19 to 81 years]). In CE, participants identified 5-10% weight loss as the threshold for having a noticeable improvement on PF and contextualized meaningful weight loss by using real-life examples (e.g., climbing stairs without becoming breathless). In CD, the majority of participants considered a 1-point change at the item level to be indicative of meaningful improvement on both PRO measures. Conclusions: The combined CE and CD approach facilitated better understanding of meaningful change by participants, providing evidence that a 1-point change, the smallest detectable change on both the SF-36v2 (acute) and IWQOL-Lite-CT, is a CIC in people with overweight or obesity. Disclosure J. Poon: Employee; Self; Eli Lilly and Company. C. Marshall: Other Relationship; Self; Eli Lilly and Company. C. Johnson: Other Relationship; Self; Eli Lilly and Company. H. Pegram: Other Relationship; Self; Eli Lilly and Company. M. Hunter: Other Relationship; Self; DRG Abacus. H. Kan: Employee; Self; Eli Lilly and Company. N. Ahmad: Employee; Self; Eli Lilly and Company.