What do systematic reviews say?

Theory-based oral health education/promotion interventions (HBM, TPB, SCT, HAPA, TTM, PMT, SOC, PRECEDE-PROCEED, MI) vs Control (waitlist, routine/standard oral health education, or minimal intervention)

Theory-based interventions significantly improved oral health-related quality of life (SMD 7.38; low certainty), with very high heterogeneity.

• Health promotion theory-based educational interventions for improving oral health in children and adolescents: a… 2025 All outcomes

  Post-intervention (follow-up 0.5 to 12 months, varies by study) · School-based and community settings; multiple countries (predominantly Iran; also Pakistan, Hong Kong, Lithuania, Thailand) · Overall
  SMD 7.38 [5.57, 9.19]
  4 studies · 4751 participants
  Low

Chemotherapy (any regimen; added to, or compared with, locoregional treatment) vs Locoregional treatment and/or an alternative chemotherapy regimen

The review found no eligible studies for this question.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy 2021 · Cochrane All outcomes
  Quality of life was a planned (protocol) outcome but no included trial provided usable quality-of-life data; the protocol was modified to report only survival/response outcomes.
  0 studies
  No studies found

Radiotherapy (morning) vs Afternoon radiotherapy

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  Bjarnason 2009: no statistically significant difference in quality of life scores (data not reported). Morning radiotherapy was associated with significantly less weight loss after 5 months.
  1 study · 216 participants
  GRADE not reported