Development and validation of a food frequency questionnaire

Area of Science:

• Nutrition Science
• Epidemiology
• Public Health

Background:

• Diet monitoring is essential for public health.
• Validated tools are needed for accurate dietary assessment in specific populations.
• Existing questionnaires require adaptation for diverse linguistic and cultural contexts.

Purpose of the Study:

• To adapt and validate a semiquantitative food frequency questionnaire (FFQ) for use in Quebec, Canada.
• To assess the reliability of the FFQ in capturing long-term food consumption among adults.
• To provide a culturally relevant dietary assessment tool for French and English speakers in Quebec.

Main Methods:

• Adapted the Block National Cancer Institute Health Habits and History Questionnaire into French and English.
• Recruited a representative sample of Quebec adults (n=248) via random digit dialling.
• Validated the FFQ against four nonconsecutive food records (FRs) in a subsample (n=94).

Main Results:

• Spearman correlation analyses showed significant positive correlations (r=0.32-0.58, p<0.001) between FFQ and FR nutrient data, particularly for women.
• Cross-classification analysis indicated 39% agreement in identical quartiles and 78% in identical or contiguous quartiles.
• Minimal misclassification (4%) was observed between the FFQ and FR methods.

Conclusions:

• The adapted FFQ demonstrates relative validity for assessing usual dietary intake in Quebec adults.
• This validated instrument can support nutritional research and public health surveillance in the region.
• The FFQ is a practical tool for diet monitoring in a bilingual population.