Study design

Study setting and duration

Patient recruitment and eligibility criteria

Sample collection protocol

Caries assessment

Reagents and chemicals

Preparation of standards

Sample preparation and derivatization

Chromatographic analysis

Calibration and quality control

Conceptual framework and analytical rationale

Confounder identification using directed acyclic graph (DAG)

Statistical analysis

Salivary monosodium glutamate (MSG) levels in relation to dental caries

Association with DMFT index

Association with caries index

Data visualization and pattern recognition

Logistic regression analysis