The aim of the current study was to provide initial psychometric validation of a questionnaire version of the ChEDE with instructions to assess binge eating in overweight adolescents. In order to examine its convergent validity, the YEDE-Q was compared to two other measures designed to assess ED symptomatology in youth. The YEDE-Q was found to have significant agreement with the ChEDE in the measurement of most ED attitudes and behaviors. The YEDE-Q also showed significant agreement with the QEWP-A in the measurement of shape and weight concerns, but not in the measurement of ED behaviors.
When comparing the YEDE-Q with the ChEDE, significant correlations were yielded for all four subscale scores and the global score. The YEDE-Q consistently yielded higher mean subscale scores and frequency ratings than the ChEDE, a difference that was significant for all but the Restraint subscale and OO episodes comparisons. This finding converges with previous comparisons between questionnaire and interview forms of the EDE [41
], and was likely due to the fact that the ChEDE allows for detailed probing of interviewees to ensure complete comprehension of items.
Measures of internal consistency were lower than those reported for both the ChEDE [53
] and the EDE-Q [54
] on all but the Shape Concern subscale (see ), and two subscales, Restraint and Eating Concern, did not reach the standard for acceptable internal consistency proposed by Nunnally (alpha = .70) [65
]. However, all subscales reached the minimum alpha of .60 suggested by Nunnally [65
] for pilot measures. Only the Restraint subscale was considerably below the more conservative proposed alpha of .70, possibly because this subscale contains items primarily assessing attempts
to perform a behavior rather than actual successful implementation
of that behavior. These items may be conceptually more difficult for younger respondents to understand given that they contain both a cognitive and a behavioral element, with words such as “try” indicating both subjective, mental efforts and objective attempts (e.g., wanting to restrict food intake and making actual overt attempts to do so). Empirically, elimination of the “Empty Stomach” item (“On how many of the past 28 days have you wanted your stomach to be empty—to not have any food in it at all?”) would raise the internal consistency of the Restraint subscale the most (to .71), which is not surprising given that the current sample did not include individuals with AN or BN, the population in whom this item would have the most relevance; however, removing this item from the measure is not indicated since it would appear to have more diagnostic importance in eating disordered individuals, as supported by previous examinations of internal consistency of ChEDE and EDE-Q subscales [53
]. Future studies should examine the internal consistency of this subscale among youth with EDs, and possibly explore means for improvement.
The YEDE-Q and the ChEDE showed significant agreement for both OBE days and episodes, representing a considerable improvement over other instruments assessing ED symptomatology in youth [41
]. This may reflect the addition of the binge rating instructions for youth, which offers detailed explanations of ambiguous concepts such as “objectively large” and “loss of control.”
When holding the ChEDE as the “gold standard,” the YEDE-Q appeared to be adequate in its detection of individuals endorsing binge eating, identifying only 3 (8.6%) false-positives and 0 (0%) false negatives. It is encouraging that the YEDE-Q overestimated rather than underestimated cases of binge eating, especially if it is to be used as a screening instrument. Indeed, there is less danger in falsely identifying an individual endorsing binge eating and needlessly providing further assessment than there is in overlooking an adolescent suffering from binge eating problems who could potentially benefit from further assessment and early intervention.
Comparisons between the YEDE-Q and the ChEDE yielded non-significant correlations for SBE and OO episodes, as well as driven exercise. This could be attributed to the ChEDE’s investigator-based format, in which the assessor applies objective criteria to information supplied by the respondent in order to determine frequency and severity ratings; thus, episodes considered SBEs, OOs, or driven exercise by the respondent may not have been deemed as such by the ChEDE interviewer’s criteria, and vice versa. Although OBEs are the only eating episodes involved in generating ED diagnoses, future iterations of the YEDE-Q may explore ways to improve agreement between the YEDE-Q and the ChEDE on ratings of SBEs and OOs, as these items may be useful for identifying individuals at risk for developing an ED.
Significant correlations were found for the QEWP-A item assessing importance of shape and weight, and the YEDE-Q’s Shape Concern and Weight Concern subscales as well as individual items assessing the importance of shape and weight. In contrast, there was low agreement between the QEWP-A and the YEDE-Q in the measurement of binge eating. The QEWP-A also showed non-significant agreement with the ChEDE in the measurement of OBEs, providing initial evidence that the lack of agreement between the QEWP-A and the YEDE-Q may be due to the low sensitivity of the QEWP-A, corroborating reports by Tanofsky-Kraff and colleauges [42
Limitations of the current study include the small sample size, as well as the use of an adolescent sample that was not drawn from an ED population. Although age was not found to predict better agreement between the YEDE-Q and the ChEDE, the exclusion of participants below a sixth grade reading level likely enhanced comprehension of items. Thus, the absence of an interaction between age and YEDE-Q scores could represent a ceiling effect. Indeed, it would be premature to endorse the YEDE-Q as a measure for youth outside of the current sample’s age range, as children (i.e., below age 12) are those most likely to exhibit difficulties completing a questionnaire version of the EDE. Specifically, children may not be able to understand complex nuances of questionnaire items without assistance, such as the difference between shape and weight; distinctions regarding intending to, attempting to, and actually performing a behavior; and fine gradations in severity levels. Thus, further validation of the YEDE-Q as compared to the ChEDE in children is indicated. In addition, the use of a low-pathology group precluded generalization to ED populations. It is unclear whether significant correlations would be found for greater severity of symptoms, or whether the high correlations found in the current study should be attributed to floor effects. However, given that the current sample of overweight youth represents a group at elevated risk for eating pathology in whom assessment is clearly warranted, study results suggest that the YEDE-Q could be a useful measure for individuals with more severe eating problems. Indeed, the current study represents a crucial first step in paving the way for future YEDE-Q validation work with relevant populations.
In terms of future directions, larger replication studies clearly need to be undertaken in order to determine the generalizability of findings to younger age groups, populations with lower reading abilities or those for whom English is not the primary language, and individuals with EDs. Furthermore, normative data should be established in ED subgroups, as well as obese versus normal-weight youth, in order to facilitate use of the YEDE-Q as a screening questionnaire. The YEDE-Q should also be compared to the EDE-Q in order to determine whether it confers any benefit beyond the more established measure.
In conclusion, the YEDE-Q appears to be a promising measure for the assessment of ED behaviors and attitudes in overweight adolescents. While the ChEDE remains the measure of choice in ED assessment due to its allowance for detailed probing by the interviewer, the YEDE-Q shows the potential to contribute in important ways as both a screen and a research instrument. Advantages include its relatively rapid administration, and its cost-effectiveness in terms of minimal assessor burden. Further examination will determine its suitability for children and other eating- and weight-disordered populations.