Methodological considerations when measuring oral health-related quality of life.

BACKGROUND: Dental patient-reported outcomes (dPROs) and their measures, dPROMs, are fundamental for evidence-based dentistry. However when selecting, applying and evaluating an instrument with a focus on OHRQoL assessment for adults, several methodological considerations are essential to derive valid and meaningful results.
METHODS: In this review article, criteria for selecting the appropriate OHRQoL instrument, aspects of administering the instrument and how to evaluate resulting scores of single and multiple assessments are presented and critically assessed.
RESULTS: Oral disease-generic and dimension-generic instruments capturing the entire construct OHRQoL allow for best comparability of findings across different diseases, settings and populations, with the Oral Health Impact Profile (OHIP) being the most often used and methodologically best investigated one. It is available in several versions with the 5-item version being the one with the lowest burden for the patient. Responses are given on a 5-point ordinal rating scale, the recommended response scale for dPROMs. A 7-day recall period allows for assessment of short-term effects. Clinically relevant effects of item or instrument order or administration method on OHIP scores do not seem to be likely. OHIP summary and dimension scores can be compared to norms from general population or different patient populations. Change scores should be set into context with the minimal important difference of the instrument.
CONCLUSION: OHIP-5 has greatest potential to be used across all settings for assessment and evaluation of OHRQoL in adults. It allows a comprehensive characterising of patients suffering from oral diseases and of this impact using OHRQoL dimensions.