Utilisation of a think-aloud protocol to validate a self-reported periodontitis questionnaire

Area of Science:

• Oral health research
• Epidemiology
• Cognitive psychology

Background:

• Diagnosing periodontitis typically involves clinical and radiographic methods, which are resource-intensive.
• Self-reported questionnaires offer a scalable alternative for population-level assessments.
• Cognitive validation of these questionnaires is crucial but underexplored.

Purpose of the Study:

• To cognitively validate a self-reported periodontitis questionnaire using a think-aloud approach.
• To assess participant interpretation and comprehension of questionnaire items.
• To identify potential sources of information bias in self-reported data.

Main Methods:

• 20 UK-based English speakers participated in online think-aloud interviews.
• A 15-item self-reported periodontitis questionnaire with 2 open-ended questions was used.
• Interviews were transcribed, coded for comprehension, and analyzed using content analysis.

Main Results:

• Most questionnaire items were well understood by participants.
• Two specific items were identified as problematic: one misinterpreted, one poorly understood.
• Content analysis of open-ended questions corroborated think-aloud findings, informing revisions.

Conclusions:

• The think-aloud method effectively revealed participant understanding of periodontitis questionnaire items.
• Identified question ambiguities may explain lower sensitivity in self-reported data.
• Ensuring clear question comprehension is vital to minimize information bias in epidemiological surveys.