In periodontics, what term describes a factor that serves as an indicator, determinant, or marker associated with a particular condition?

Correct answer: C. Risk factor

• A. A prognostic factor predicts the OUTCOME of disease once it is already present — a different concept from risk of developing it.
• B. 'Predictor factor' is not standard periodontal terminology.
• C. Correct. A RISK FACTOR is an exposure, behavior, or characteristic associated with increased probability of disease. Periodontal terminology distinguishes: risk factors (modifiable, e.g. smoking, diabetes), risk determinants/background characteristics (non-modifiable, e.g. genetics, age), risk indicators (associated in cross-sectional but not longitudinal studies), and risk markers/predictors (associated with disease but not causal, e.g. prior attachment loss).
• D. A diagnostic factor is used to identify existing disease, not to estimate risk.