The factor structure of the General Health Questionnaire (GHQ): a scaled version for general practice in Spain

Area of Science:

• Psychological assessment
• Psychometrics
• Mental health screening

Background:

• The General Health Questionnaire (GHQ-28) is a widely used mental health screening tool.
• Direct translation of the GHQ-28 for non-English populations may reduce its predictive accuracy.
• Cultural adaptation is crucial for valid health assessments in diverse populations.

Purpose of the Study:

• To adapt and validate the General Health Questionnaire (GHQ-28) for use in a Spanish primary care setting.
• To investigate the psychometric properties of a culturally adapted GHQ-28 in Spanish adults.
• To compare the structure and item content of the adapted GHQ-28 with the original English version.

Main Methods:

• Replication of the GHQ-28 construction process using a Spanish primary care sample.
• Principal components analysis was employed to refine the questionnaire structure.
• Item analysis and validation were conducted on the Spanish sample.

Main Results:

• Two shorter versions of the GHQ-28 were proposed: one with 30 items and six scales, and another with 28 items and four scales.
• The adapted GHQ-28 for the Spanish sample differed in item composition from the original English version (only 21 identical items).
• A distinct scale for 'Sleep disturbances' emerged in the Spanish version, separate from anxiety items, unlike the original English version.

Conclusions:

• The adapted GHQ-28 is a successful and culturally relevant tool for mental health screening in the Spanish primary care population.
• The study highlights the importance of cultural adaptation in psychometric instrument development.
• The findings suggest that the Spanish version of the GHQ-28 offers improved diagnostic utility for the target population.