Psychometric properties of the original Inflammatory Bowel Disease Questionnaire, a Spanish version.
BACKGROUND
The Inflammatory Bowel Disease Questionnaire (IBDQ) was developed by Guyatt et al. (1989) and it is the most widely used health-related quality of life instrument for patients with Crohn's disease (CD) and ulcerative colitis (UC). The aim of this study was to assess the psychometric properties of a Spanish version of the original IBDQ by examining the instrument's underlying factor structure, the internal and external validity, and the internal consistency reliability.


METHODS
One hundred and forty seven patients (76 CD, 71 UC) completed the Spanish version of the IBDQ, the Hospital Anxiety and Depression Scale (HADS) and the Temperament and Character Inventory (TCI). Clinical activity was assessed by the CDAI and the Truelove-Witts index.


RESULTS
The confirmatory factor analysis of the IBDQ failed to reproduce the original four-factor structure proposed by Guyatt et al. We found that the Spanish version of the IBDQ consists also of four underlying factors, but the content of each factor and the items included were slightly different. Psychometric testing of the IBDQ revealed that the questionnaire has an acceptable internal and external validity, and a high internal reliability.


CONCLUSIONS
Although confirmatory factor analyses failed to reproduce the original psychometric structure of IBDQ, it seems that the Spanish version of this instrument proved to be valid and reliable for assessing health related quality of life in inflammatory bowel disease patients.
Vidal
Angela
A
Department of Clinical Psychology, Hospital Clínic de Barcelona, Institut Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain. anvidal@clinic.ub.es
Gómez-Gil
Esther
E
Sans
Miquel
M
Portella
Maria J
MJ
Salamero
Manel
M
Piqué
Josep M
JM
Panés
Julián
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D001007:Anxiety / Q000175:diagnosis / Q000523:psychology; D003863:Depression / Q000175:diagnosis / Q000523:psychology; D004644:Emotions; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology / Q000523:psychology; D010555:Personality Inventory; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012919:Social Behavior; D013030:Spain; D011795:Surveys and Questionnaires; D013694:Temperament