Exploring the validity and internal consistency of the 12-point Mediterranean Diet Adherence Screener among Lebanese pregnant women

Abstract

Although 14-MEDAS is widely used for dietary assessment, it has not been validated in pregnant Lebanese women. This study assesses its validity and internal consistency against a Food Frequency Questionnaire (FFQ) and 24-hour recalls (24HR). A cross-sectional study with 500 pregnant women was conducted between March and October 2023. Food consumption data were gathered using a validated FFQ and three non-consecutive 24-HR to validate the 14-MEDAS. Adherence thresholds were adjusted for the removal of the alcohol item (contraindicated during pregnancy) and olive oil quantity (low communalities: < 0.30), leading to a maximum score of 12 (12-MEDAS). Internal consistency, as measured by KR-21, was acceptable (0.76) reflecting the formative nature of the scale. Factor analysis revealed a four-factor structure explaining 46.28% of the variance. The 12-MEDAS demonstrated suboptimal relative validity. While it provides a quick assessment of adherence to the Mediterranean Diet, discrepancies between the 12-MEDAS and reference methods (FFQ and 24HR) likely stem from the tool’s inability to account for pregnancy- and locally-specific food groups and habits, as well as measurement errors inherent to self-reported methods. The results warrant a cultural and physiological adaptation, such as adjusting for the recommended alcohol abstinence, and considering local food sources and eating habits.