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Search review questions
Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 0.7%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Accelerated radiotherapy with concomitant boost vs Conventional (standard) fractionation radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Accelerated/boost vs conventional, disease free survival: all four trials provided data; pooled estimate showed a statistically significant difference in favour of the accelerated/boost schedule, with statistical… | 4 studies · 1203 participants | Ungraded |
Split-course radiotherapy vs Accelerated radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 2 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 1.33 [0.67, 2.67] | 1 study · 110 participants | Ungraded |
Pre-operative and post-operative radiotherapy vs Post-operative radiotherapy alone Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.13 [0.78, 1.64] | 1 study | Ungraded |
Hyperfractionated radiotherapy vs Conventional (standard) fractionation radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.78 [0.68, 0.90] | 3 studies · 966 participants | Ungraded |
Split-course radiotherapy vs Accelerated radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 2 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 0.83 [0.29, 2.42] | 1 study · 110 participants | Ungraded |
Pre-operative and post-operative radiotherapy vs Post-operative radiotherapy alone Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.13 [0.78, 1.64] | 1 study | Ungraded |
Neutron radiotherapy vs Conventional photon radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 5 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 0.97 [0.69, 1.36] | 1 study | Ungraded |
Altered fractionation radiotherapy (hyperfractionated and/or accelerated) vs Conventional (standard) fractionation radiotherapy Mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 5 years, All included studies Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.86 [0.76, 0.98] | 13 studies · 3751 participants | Very low |
Accelerated radiotherapy (no split, boost or hyperfractionation) vs Conventional (standard) fractionation radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | 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 | Ungraded |
Hyperfractionated radiotherapy vs Conventional (standard) fractionation radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Hyperfractionated vs conventional, disease free survival: data available for one trial (Fu 2000); no statistically significant difference (Analysis 1.3). No pooled estimate reported. | 1 study | Ungraded |
Lower total dose radiotherapy (67.2 Gy over 5.6 weeks) vs Conventional/standard total dose radiotherapy (72 Gy) Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.13 [0.78, 1.64] | 1 study | Ungraded |
Higher total dose radiotherapy (76.8 Gy over 6.4 weeks) vs Conventional/standard total dose radiotherapy (72 Gy) Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.08 [0.69, 1.70] | 1 study | Ungraded |
Hyperfractionated/accelerated/split-course radiotherapy vs Conventional (standard) fractionation radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.02 [0.90, 1.17] | 4 studies · 1299 participants | Ungraded |
Morning radiotherapy vs Afternoon radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 2 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 1.09 [0.74, 1.59] | 1 study · 216 participants | Ungraded |
Hyperfractionated/accelerated/split-course radiotherapy vs Conventional (standard) fractionation radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Hyperfractionated/accelerated/split vs conventional, disease free survival: two trials (Fu 2000, Olmi 2003); results contradictory with substantial statistical heterogeneity (P = 0.02, I2 = 82%); no pooled estimate… | 2 studies | Ungraded |
Split-course radiotherapy vs Accelerated radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 2 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 1.00 [0.82, 1.22] | 1 study · 110 participants | Ungraded |
Mixed beam (neutron and photon) radiotherapy vs Conventional photon radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.12 [0.92, 1.36] | 1 study · 327 participants | Ungraded |
Intensity modulated radiotherapy (IMRT) vs Conventional or other radiotherapy Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Discussion: 'There are currently no trials of IMRT in this systematic review' (the PARSPORT trial was underway, expected 2013). No eligible trials of intensity modulated radiotherapy identified. | 0 studies | No studies |
Hyperfractionated/accelerated radiotherapy vs Conventional (standard) fractionation radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Hyperfractionated/accelerated vs conventional, disease free survival: one trial (Poulsen 2001); no statistically significant difference (Analysis 1.3). No pooled estimate. | 1 study | Ungraded |
Neutron radiotherapy vs Conventional photon radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.10 [0.90, 1.34] | 3 studies | Ungraded |
Accelerated/split-course radiotherapy vs Conventional (standard) fractionation radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 5 years Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 1.17 [0.57, 2.43] | 1 study · 147 participants | Ungraded |
Hyperfractionated/accelerated split-course radiotherapy vs Accelerated radiotherapy with concomitant boost Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Fu 1995: no significant difference in locoregional control; data not presented in a way that allows calculation of an HR. | 1 study · 75 participants | Ungraded |
Morning radiotherapy vs Afternoon radiotherapy Quality of life · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | 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 | Ungraded |
Morning radiotherapy vs Afternoon radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.92 [0.60, 1.42] | 1 study · 216 participants | Ungraded |
Lower total dose radiotherapy (67.2 Gy over 5.6 weeks) vs Conventional/standard total dose radiotherapy (72 Gy) Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 1.38 [0.83, 2.29] | 1 study | Ungraded |
Altered fractionation radiotherapy (hyperfractionated and/or accelerated) vs Conventional (standard) fractionation radiotherapy Mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · 5 years, Studies at low risk of bias (sensitivity analysis) Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.93 [0.80, 1.07] | 5 studies · 1511 participants | Moderate |
Pre-operative radiotherapy (plus surgery) vs Surgery alone Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.83 [0.64, 1.07] | 1 study | Ungraded |
Accelerated radiotherapy (no split, boost or hyperfractionation) vs Conventional (standard) fractionation radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Accelerated vs conventional, locoregional control: one trial (Skladowski 2006); a statistically significant difference in favour of the altered fractionation was shown (Analysis 1.2). No numeric estimate given. | 1 study | Ungraded |
Higher total dose radiotherapy (76.8 Gy over 6.4 weeks) vs Conventional/standard total dose radiotherapy (72 Gy) Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.78 [0.55, 1.11] | 1 study | Ungraded |
Hyperfractionated/accelerated/split-course radiotherapy vs Conventional (standard) fractionation radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.86 [0.74, 1.01] | 4 studies · 1299 participants | Ungraded |
Hyperfractionated/accelerated radiotherapy vs Conventional (standard) fractionation radiotherapy Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.87 [0.75, 1.00] | 4 studies · 1071 participants | Ungraded |
Pre-operative and post-operative radiotherapy vs Post-operative radiotherapy alone Total mortality · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.67 [0.35, 1.28] | 1 study | Ungraded |
Altered fractionation radiotherapy plus chemotherapy vs Chemoradiotherapy with standard (conventional) fractionation Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Discussion: 'there are no completed trials of altered fractionation plus chemotherapy versus chemoradiotherapy with standard fractionation.' | 0 studies | No studies |
Accelerated radiotherapy (no split, boost or hyperfractionation) vs Conventional (standard) fractionation radiotherapy Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Accelerated vs conventional, disease free survival: both trials reported this, but substantial clinical and statistical heterogeneity (P = 0.0004, I2 = 92%) meant a pooled analysis was not reported (Analysis 1.3). | 2 studies | Ungraded |
Hyperfractionated/accelerated split-course radiotherapy vs Accelerated radiotherapy with concomitant boost Disease free survival · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Fu 1995: no significant difference in disease free survival; data not presented in a way that allows calculation of an HR. | 1 study · 75 participants | Ungraded |
Altered fractionation radiotherapy (hyperfractionated and/or accelerated) vs Conventional (standard) fractionation radiotherapy Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | HR 0.79 [0.70, 0.89] | 11 studies | Ungraded |
Pre-operative radiotherapy (plus surgery) vs Surgery alone Locoregional control · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… · Timing unclear Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | RR 0.63 [0.28, 1.46] | 1 study | Ungraded |
Altered fractionation radiotherapy vs Chemoradiotherapy (concurrent, standard fractionation) Outcome NR · People with primary squamous cell carcinoma of the oral cavity (ICD-O C01-C06) or oropharynx (ICD-O C09-C10); head and… Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy (2010) · Cochrane | Discussion: altered fractionation radiotherapy 'has not been directly compared to chemoradiotherapy'. No eligible head-to-head trials. | 0 studies | No studies |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Restoration failure at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 3.29 [0.12, 89.81] | 1 study · 22 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Secondary caries at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 3.13 [0.12, 80.68] | 1 study · 48 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Marginal integrity (cervical) failures at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Marginal integrity (cervical) failures at 24 months: odds ratio not estimable - no events recorded at this interval. | 1 study · 48 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Surface texture failures at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 1.00 [0.22, 4.56] | 1 study · 48 participants | Ungraded |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Occlusion at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Occlusion at 6 months: odds ratio not estimable - no events recorded at the 6-month evaluation. | 1 study · 22 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Cervical gaps on bitewing X-rays at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 1.00 [0.13, 7.75] | 1 study · 48 participants | Ungraded |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Proximal contact at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Proximal contact at 6 months: odds ratio not estimable - no events recorded at the 6-month evaluation. | 1 study · 22 participants | Ungraded |
Dental fillings (restorations) vs Dental extractions Outcome NR · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · Minimum 6 months follow-up Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | "No studies were found that compared restorations versus extractions or no treatment as an intervention in children with caries in the primary dentition." | NR | No studies |
Aesthetic (resin-veneered) crowns vs Conventional metal (stainless steel) crowns Marginal integrity at 6 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Marginal integrity at 6 months: odds ratio not estimable - no events recorded at the 6-month evaluation. | 1 study · 22 participants | Ungraded |
Resin-modified glass ionomer (Vitremer) vs Amalgam Marginal integrity, wear, surface texture, staining and secondary caries (Ryge criteria) at 6-12 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 6-12 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | Marginal integrity, wear, surface texture, axial contour, staining and secondary caries (Ryge criteria) at 6 and 12 months: odds ratios not estimable - no events recorded, implying equal performance of the two materials. | 1 study · 60 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Marginal integrity (occlusal) failures at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 10.76 [0.55, 211.78] | 1 study · 48 participants | Ungraded |
Compomer (Dyract) vs Amalgam (Tytin) Radiolucencies on bitewing X-rays at 24 months · Children aged 12 years or younger with tooth decay involving at least one tooth in the primary dentition, symptomatic… · 24 months Dental fillings for the treatment of caries in the primary dentition (2009) · Cochrane | OR 4.53 [0.83, 24.65] | 1 study · 48 participants | Ungraded |