The modified weight bias internalization scale: psychometric validation of three versions in a sample of university students.

PURPOSE

The Modified Weight Bias Internalization Scale (WBIS-M) is perhaps the most frequently used measure of internalised weight bias and has growing support for its psychometric properties. However, there is a lack of clarity regarding how many items are necessary for adequate interpretation of the WBIS-M and limited study of internalised weight bias in young adults. The aims of this study are to evaluate different versions of the WBIS-M, assessing structural and convergent validity.

METHODS

The current study recruited 205 university students (aged 18-46, mean body mass index = 22.60 kg/m) in the UK and examined the factor structure, reliability, and convergent validity of the WBIS-M, looking at 11-item, 10-item, and 9-item versions.

RESULTS

Confirmatory factor analysis suggested that a 10-item version of the WBIS-M showed acceptable structural validity and expected correlations with relevant constructs (depression, anxiety, weight status, and eating pathology). Estimates of internal consistency reliability were high for all three versions.

CONCLUSION

Given potential problems with one item, the 10-item WBIS-M presents a measure of internalised weight bias with sound psychometric properties in young adults.

LEVEL OF EVIDENCE

Level III, well-designed cohort study.