Validation of the SCOFF questionnaire for screening of eating disorders among Mexican university students

To evaluate the criterion validity and diagnostic utility of the SCOFF, a brief eating disorder (ED) screening instrument, in a Mexican sample.

The study was conducted in two phases in 2012. Phase I involved the administration of self-report measures [the SCOFF and the Eating Disorder Inventory-2, (EDI-2)] to 1057 students aged 17-56 years (M age = 21.0, SD = 3.4; 67 % female) from three colleges at the Universidad Autónoma de San Luis Potosí, Mexico. In Phase II, a random subsample of these students (n = 104) participated in the eating disorder examination, a structured interview that yields ED diagnoses. Analyses were conducted to evaluate the SCOFF's criterion validity by examining (a) correlations between scores on the SCOFF and the EDI-2 and (b) the SCOFF's ability to differentiate diagnosed ED cases and non-cases.

EDI-2 subscales showed high correlations with the SCOFF scores proving initial evidence of criterion validity. A score of two points on the SCOFF optimized the sensitivity (78 %) and specificity (84 %). With this cutoff, the SCOFF correctly classified over half the cases (PPV = 58 %) and screened out the majority of non-cases (NPV = 93 %) providing further evidence of criterion validity. Analyses were repeated separately for men and women, yielding gender-specific information on the SCOFF's performance.

Taken as a whole, results indicated that the SCOFF can be a useful tool for identifying Mexican university students who are at risk of eating disorders.