Transcultural adaptation of the Night Eating Questionnaire (NEQ) for its use in the Spanish population

Establishing valid and reliable methods of assessing night eating symptoms is an important goal to maximize identification and treatment of the night eating syndrome (NES). The 14-item Night Eating Questionnaire (NEQ) is the only published and validated assessment instrument but is not yet adapted to Spanish.

We examined the factor structure, internal consistency and validity of the NEQ in Spanish. The study had 4 phases: a) translation from English to Spanish; b) back-translation from Spanish to English, c) administration of translated version to a Spanish sample, and d) a re-test in 36 participants two weeks later. Reliability, stability, and scale structure were evaluated by Cronbach's α, test-re-test, and factor analysis, respectively. Divergent validity was assessed by correlation with the Spanish versions of the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory (BDI-II).

Two-hundred forty-four individuals (181 f; BMI 34.3±10 kg/m(2); age 40.5±15 y) completed the questionnaire. The mean NEQ score was 12.5±7. The Cronbach's α coefficient for the total score was 0.79, the intraclass correlation was 0.85, and the factor analysis yielded a similar four factor solution as the original scale. Correlation for the test-re-test total score was 0.86. Total NEQ score was significantly correlated with the BDI-II (r=0.48 p<0.001), but this correlation was not significant during the test-re-test (r=0.28, p=0.10) or with STAI at either time point (0.05, p=0.40; r=0.07, p=0.69, respectively).

The Spanish version of the NEQ demonstrated adequate internal consistency for the majority of domains and excellent reproducibility. There was divergent validity with anxiety and a relationship between night eating and depression. These results suggest that the Spanish-version of the NEQ is an instrument that is valid for use in clinical research.