What do systematic reviews say?

Mediterranean dietary intervention vs another dietary intervention

Mediterranean dietary intervention showed no clear difference in total mortality compared with another dietary intervention (low certainty).

• Mediterranean‐style diet for the primary and secondary prevention of cardiovascular disease 2019 · Cochrane Headline outcomes only
  HR 1 [0.81, 1.24]
  1 study · 7447 participants
  Low

Mediterranean dietary intervention vs no intervention or minimal intervention

The review found no eligible studies for this question.

• Mediterranean‐style diet for the primary and secondary prevention of cardiovascular disease 2019 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Internet‐based interventions vs usual care or no treatment

Internet‐based interventions showed no clear difference in total mortality compared with usual care or no care (low certainty).

• Internet‐based interventions for the secondary prevention of coronary heart disease 2015 · Cochrane Headline outcomes only
  OR 0.27 [0.04, 1.63]
  6 studies · 895 participants
  Low

Mediterranean dietary intervention vs usual care

Mediterranean dietary intervention may leads to lower total mortality compared with usual care (low certainty).

• Mediterranean‐style diet for the primary and secondary prevention of cardiovascular disease 2019 · Cochrane Headline outcomes only
  RR 0.44 [0.21, 0.92]
  1 study · 605 participants
  Low

Psychological intervention with or without other rehabilitation vs control (usual care/other rehabilitation)

Psychological intervention with or without other rehabilitation showed no clear difference in total mortalityDeaths compared with control (usual care/other rehabilitation) (moderate certainty).

• Psychological interventions for coronary heart disease 2017 · Cochrane Headline outcomes only
  RR 0.9 [0.77, 1.05]
  23 studies · 7776 participants
  Moderate

Surgery plus radiotherapy vs Radiotherapy alone

It is very uncertain whether surgery plus radiotherapy changes total mortality compared with radiotherapy alone (very low certainty).

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes

  3 years
  HR 0.24 [0.10, 0.59]
  1 study · 35 participants
  Very low

Elective radical (comprehensive) neck dissection vs Elective selective neck dissection

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes
  Total mortality: 2 trials reported HR but could not be pooled (different surgical procedures); neither indicated a difference (BHNCSG 1998 HR 1.14, 0.70 to 1.86; Bier 1994 HR 0.87, 0.41 to 1.83); 252 participants (2…
  2 studies · 252 participants
  Very low

Surgery vs Radiotherapy alone

Surgery showed no clear difference in total mortality compared with radiotherapy alone (low certainty).

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes

  3 years
  HR 0.83 [0.09, 7.46]
  1 study · 68 participants
  Low

Surgery plus radiotherapy vs Chemotherapy (chemoradiotherapy)

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes

  oral cavity
  Total mortality: study reported survival significantly better with surgery and RT vs chemoradiotherapy, but no useable data; 32 participants (1 RCT, Iyer 2015 oral cavity subgroup).
  1 study · 32 participants
  Very low

PET-CT following chemoradiotherapy (neck dissection only if no/incomplete response) vs Planned neck dissection before or after chemoradiotherapy

PET-CT following chemoradiotherapy (neck dissection only if… showed no clear difference in total mortality compared with planned neck dissection before or after chemoradiotherapy (moderate certainty).

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes

  3 years
  HR 0.92 [0.65, 1.31]
  1 study · 564 participants
  Moderate

Superselective neck dissection vs Elective selective neck dissection

The review found no eligible studies for this question.

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes
  Total mortality: not reported.
  0 studies
  No studies found

Sentinel node biopsy (neck dissection only if biopsy positive) vs Elective neck dissection

Sentinel node biopsy (neck dissection only if biopsy positive) showed no clear difference in total mortality compared with elective neck dissection (low certainty).

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes

  3 years
  HR 1.00 [0.90, 1.11]
  1 study · 279 participants
  Low

Supraomohyoid neck dissection vs Modified radical neck dissection

• Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment 2023 · Cochrane All outcomes
  Total mortality: reported but not usable (Guo 2014: during follow-up 113/322 (35.1%) died; SOND 53, MRND 60). No GRADE rating.
  1 study
  GRADE not reported

Hyperfractionated/accelerated split-course radiotherapy vs Accelerated radiotherapy with concomitant boost

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  Hyperfractionated/accelerated split course vs accelerated boost (Fu 1995, feasibility study, 75 participants): authors report no significant difference in total mortality; data not presented in a way that allows…
  1 study · 75 participants
  GRADE not reported

Accelerated radiotherapy with concomitant boost vs Conventional (standard) fractionation radiotherapy

Accelerated radiotherapy with concomitant boost showed no clear difference in total mortality compared with conventional (standard) fractionation radiotherapy; GRADE not reported.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  HR 0.95 [0.80, 1.13]
  3 studies · 1203 participants
  GRADE not reported

Hyperfractionated radiotherapy vs Conventional (standard) fractionation radiotherapy

Hyperfractionated radiotherapy led to lower total mortality compared with conventional (standard) fractionation radiotherapy; GRADE not reported.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  HR 0.78 [0.68, 0.90]
  3 studies · 966 participants
  GRADE not reported

Accelerated radiotherapy (no split, boost or hyperfractionation) vs Conventional (standard) fractionation radiotherapy

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  Accelerated vs conventional, total mortality: only one trial reported data (Skladowski 2006; IPD available). A statistically significant difference in favour of the altered fractionation was shown (Analysis 1.1). No…
  1 study
  GRADE not reported

Higher total dose radiotherapy (76.8 Gy over 6.4 weeks) vs conventional dose RT

Higher total dose radiotherapy (76.8 Gy over 6.4 weeks) showed no clear difference in total mortality compared with conventional/standard total dose radiotherapy (72 Gy); GRADE not reported.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  HR 1.08 [0.69, 1.70]
  1 study
  GRADE not reported

Hyperfractionated/accelerated/split-course radiotherapy vs Conventional (standard) fractionation radiotherapy

Hyperfractionated/accelerated/split-course radiotherapy showed no clear difference in total mortality compared with conventional (standard) fractionation radiotherapy; GRADE not reported.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes
  HR 1.02 [0.90, 1.17]
  4 studies · 1299 participants
  GRADE not reported

Radiotherapy (morning) vs Afternoon radiotherapy

Morning radiotherapy showed no clear difference in total mortality compared with afternoon radiotherapy; GRADE not reported.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy 2010 · Cochrane All outcomes

  2 years
  RR 1.09 [0.74, 1.59]
  1 study · 216 participants
  GRADE not reported