Rapid Assessment of Reward‐Related Eating: The RED‐X5

Abstract

Objective: The prevalence of obesity has created a plethora of questionnaires characterizing psychological aspects of eating behavior, such as reward-related eating (RRE). The Reward-based Eating Drive questionnaires (RED-9, RED-13) broadly and deeply assess the RRE construct. However, large-sample research designs require shorter questionnaires that capture RRE quickly and precisely. This study sought to develop a brief, reliable, and valid version of the RED questionnaire. Methods: All-subset correlation was used to find a subset that maximally associated with the full RED-13 in two separate samples. Results were validated in a third independent sample. Internal consistency, testretest reliability, and ability to explain variance in external outcomes were also assessed. Results: A five-item questionnaire (RED-X5) correlated strongly with RED-13 in the independent sample (r = 0.95). RED-X5 demonstrated high internal consistency (omega total ≥ 0.80) and 6-month test-retest reliability (r = 0.72). RED-X5 accurately reproduced known associations between RED-13 and BMI, diabetes status, and craving for sweet and savory foods. As a novel finding, RED questionnaires predicted laboratory intake of chips. Conclusions: RED-X5 is a short, reliable, and valid measure of the RRE construct and can be readily implemented in large-sample research designs in which questionnaire space is limited.

Uncontrolled eating: a unifying heritable trait linked with obesity, overeating, personality and the brain

“…This would considerably reduce participant burden. The ADOPT initiative (Sutin et al ., ) has highlighted several short and psychometrically sound questionnaires of uncontrolled eating, which include the RED‐13/RED‐X5 (Mason et al ., ; Vainik et al ., ).…”

“…constructed the Reward‐related Eating Drive (RED‐13) questionnaire that covers variance spanning from mild to very severe forms of uncontrolled eating (Mason et al ., ). This questionnaire has been recently been shortened (Vainik et al ., ) and highlighted as a core measure in the ADOPT initiative (Accumulating Data to Optimally Predict Obesity Treatment; Sutin et al ., ).…”

Common genetic factors for uncontrolled eating mechanisms

“…The original RED‐9 was developed using questions from validated scales and involved soliciting topic expert opinions to ensure high content validity (Epel et al, 2014). The RED‐9 showed good internal consistency (ω = .87–.91 across 5 studies) and test–retest reliability ( r = .77 over a 6‐month period; Vainik, Eun Han, et al, 2019), and predicted the change in BMI from baseline ( β = .05) at an 8 year follow‐up (Epel et al, 2014). Across several studies, the RED‐13 showed better coverage of the lower end of the constructs continuum compared to the RED‐9, providing superior sensitivity to subtle changes in reward‐based eating drives, which is beneficial for understanding uncontrolled eating in non‐clinical samples (Mason et al, 2017).…”

“…The RED‐13 is an updated, further validated version that better covers the broader continuum of uncontrolled eating (Mason et al, 2017). The RED‐13 used item‐response theory to select questions that, across numerous studies, precisely probed three phenotypes: perceived loss of control over eating, lack of satiety, and preoccupation with thoughts about food (Mason et al, 2017; Vainik, Eun Han, et al, 2019). Therefore, the RED‐13 is well‐positioned to clarify the heritability of uncontrolled eating and how its genetic factors overlap with BMI, as it provides improved estimation of loss of control over eating and lack of satiety, and uniquely measures preoccupation with thoughts about food, which is an important uncontrolled eating phenotype that has not been examined in prior twin studies.…”

Understanding eating behaviours, mental health and weight change in young adults: protocol paper for an international longitudinal study

“…Reward based eating was assessed using the Rapid Assessment of Reward-Related Eating Drive (RED-X5). 41 The RED-X5 consists of five questions to assess current behaviour regarding overconsumption and preoccupation with food (eg, I don’t get full easily), answered on a 5-point Likert Scale (0/Strongly disagree to 4/Strongly agree). Responses are summed to give a total score (0–20), where a higher score indicates stronger reward-based eating.…”