What makes dietary restraint problematic? Development and validation of the Inflexible Eating Questionnaire

Abstract

This study presents the Inflexible Eating Questionnaire (IEQ), which measures the inflexible adherence to subjective eating rules. The scale's structure and psychometric properties were examined in distinct samples from the general population comprising both men and women. IEQ presented an 11-item one-dimensional structure, revealed high internal consistency, construct and temporal stability, and discriminated eating psychopathology cases from non-cases. The IEQ presented significant associations with dietary restraint, eating psychopathology, body image inflexibility, general psychopathology symptoms, and decreased intuitive eating. IEQ was a significant moderator on the association between dietary restraint and eating psychopathology symptoms. Findings suggested that the IEQ is a valid and useful instrument with potential implications for research on psychological inflexibility in disordered eating.

Relationship between work-family conflict and unhealthy eating: Does eating style matter?

“…In addition, the pattern of the findings could be partly attributable to the construct, restrained eating. In particular, a number of researchers (Duarte et al, 2017;Westenhoefer, 1991) stated that dietary restraint is a complex construct that is multi-faceted. There has been some variation in how the construct has been operationalized and measured in literature on eating (Burton, Smit, & Lightowler, 2007), ranging from cognitive restraint or intention to restrict intake, fasting/skipping meals to flexible dietary restraint or eating certain foods in limited amounts (Schaumberg et al, 2016).…”

General and Eating Disorder Specific Flexibility: Development and Validation of the Eating Disorder Flexibility Index (EDFLIX) Questionnaire

“…Self-report measures can also be useful in informing about patients’ perceived levels of cognitive-behavioral flexibility and to assess therapeutic changes in ED treatment. As such, they may be seen as valuable complimentary measures to neuropsychological testing (Lounes et al, 2011; Duarte et al, 2017). This has led to the development of several self-report questionnaires designed to assess cognitive flexibility, e.g., the Psychological Flexibility Questionnaire (PFQ) (Ben-Itzhak et al, 2014), the Cognitive Flexibility Scale (Martin and Rubin, 1995) and the Coping Flexibility Scale (Kato, 2012).…”

“…This has led to the development of several self-report questionnaires designed to assess cognitive flexibility, e.g., the Psychological Flexibility Questionnaire (PFQ) (Ben-Itzhak et al, 2014), the Cognitive Flexibility Scale (Martin and Rubin, 1995) and the Coping Flexibility Scale (Kato, 2012). To date, three self-report measures have been developed to assess flexibility in EDs; the Detail and Flexibility Questionnaire (DFlex) (Roberts et al, 2011), the Inflexible Eating Questionnaire (IEQ) (Duarte et al, 2017), and the Body Image Acceptance and Action Questionnaire (BI-AAQ) (Sandoz et al, 2013). The DFlex assesses cognitive rigidity and attention to detail in everyday situations, i.e., in a general context, but does not address topics or themes directly linked to EDs (e.g., food, eating, weight, or shape).…”

Interactions between different eating patterns on recurrent binge‐eating behavior: A machine learning approach

“…Rigid restraint beliefs and cognitions were assessed via the inflexible eating questionnaire (IEQ; Duarte, Ferreira, Pinto‐Gouveia, Trindade, & Martinho, ) and the eating subscale from the dichotomous thinking in eating disorder scale (DTES; Byrne, Allen, Dove, Watt, & Nathan, ). The 11‐item IEQ assesses an individual's perceived importance of adhering to a set of arbitrary diet rules, a sense of control derived from meeting these rules, and the distress experienced when failing to meet these rules.…”

“…Each item is rated along a 5‐point scale, ranging from 1 ( fully disagree ) to 5 ( fully agree ), and are summed to produce a total score (score range = 11 to 55). Sample items include “ not following my eating rules makes me feel inferior ” and “ even if I feel satisfied with my weight, I do not allow myself to ease my eating rules .” The internal consistency ( α > .85), 4‐week test–retest reliability ( r = .84), unidimensional structure, construct validity, and incremental validity of the IEQ have been established in community samples of Australian (Linardon, Incerti, & McLean, ) and Portuguese (Duarte et al, ) adults. IEQ total scores have also been shown to successfully discriminate between those with and without elevated eating disorder symptomatology (Duarte et al, ).…”