Telephone vs face-to-face interviews for quantitative food frequency assessment

Area of Science:

• Nutrition Science
• Public Health Research
• Epidemiology

Background:

• Accurate dietary assessment is crucial for understanding health outcomes.
• Traditional face-to-face interviews can be resource-intensive.
• Developing efficient methods for dietary data collection is essential.

Purpose of the Study:

• To develop and validate a quantitative food frequency questionnaire (FFQ) administered via telephone.
• To compare the accuracy of telephone-administered FFQs with traditional face-to-face interviews.

Main Methods:

• A comparative study involving 167 men and 158 women (aged 45-74) from diverse ethnic groups in Oahu, Hawaii.
• Two FFQ interviews (telephone and face-to-face) were conducted 4-6 months apart using identical questionnaires and portion size photographs.
• Statistical analyses included paired t-tests and intraclass correlation coefficients (ICCs) to assess agreement.

Main Results:

• Intraclass correlation coefficients (ICCs) indicated good agreement between telephone and face-to-face methods, ranging from 0.61 to 0.74.
• Agreement was not significantly influenced by age, gender, ethnicity, interview order, or education level.
• Slight increases in mean energy and nutrient intake were observed in the first interview, irrespective of method.

Conclusions:

• Telephone administration of quantitative food frequency questionnaires is a cost-efficient method for estimating usual dietary intake.
• The use of mailed food photographs aids respondents in accurately estimating portion sizes.
• This method is suitable for large-scale studies in geographically dispersed populations.