. 2018 Dec 24;11:117–130. doi: 10.2147/CMAR.S186700

Table 1.

Characteristics of the included SRs

Author and year	Study design	Search date	Objective	Design and number of included studies	Participants (n)	AMSTAR-2 score

Anderson et al, 2015¹⁵	SRM	Not given	To determine whether a wider pathological margin reduces local recurrence rates in patients with OSCC treated by primary surgery without adjuvant therapy	Cohort: 5	539	Critically low
Baujat et al, 2010¹⁶	SRM	August 2010	To study the effects of altered fractionation radiotherapy vs conventional radiotherapy on overall survival rates	RCT: 15	6,515	Low
Bessell et al, 2011¹⁷	SR	February 2011	To determine which surgical treatment modalities for oral cavity and oropharyngeal cancers result in increased overall survival, disease-free survival, progression-free survival and reduced recurrence	RCT: 7	669	High
Chan et al, 2015¹⁸	SRM	February 2015	To assess the effects of molecularly targeted therapies and immunotherapies, in addition to standard therapies, for the treatment of oral cavity or oropharyngeal cancers	RCT: 12	2,488	High
Ding et al, 2018¹⁹	SRM	November– December 2017	To compare elective neck dissection with observation or therapeutic neck dissection specifically in patients with early-stage OSCC and clinically N0 neck to explore the potential benefits of elective neck dissection	RCT: 5 Case– control: 1	865	Critically low
Furness et al, 2011²⁰	SRM	December 2010	To determine whether chemotherapy, in addition to radiotherapy and/or surgery for oral cavity and oropharyngeal cancer, results in increased overall survival, disease-free survival, progression-free survival, locoregional control and reduced recurrence	RCT: 89	16,767	Low
Glenny et al, 2010²¹	SRM	July 2010	To determine which radiotherapy regimens for oral cavity and oropharyngeal cancers result in increased overall survival, disease-free survival, progression-free survival and locoregional control	RCT: 30	6,536	Low
Gou et al, 2018²²	SRM	May 2016	To explore the survival rate and disease control in patients with histological evidence of bone invasion and to compare the differences in survival rate and disease control between patients who underwent marginal mandibular resection and those who underwent segmental mandibulectomy	Cohort: 15	1,672	Critically low
Lau et al, 2016²³	SRM	March 2016	To analyze the effect of induction chemotherapy in OSCC treatment by performing an updated SR and cumulative meta-analysis	RCT: 27	2,872	Critically low
Liang et al, 2015²⁴	SRM	April 2015	To access the feasibility of selective neck dissection in oral cancer patients with positive neck nodes	Cohort: 5	443	Critically low
Liu et al, 2013²⁵	SRM	June 2012	To compare the efficacy and safety of high-dose rate and low-dose rate brachytherapy in treating early-stage oral cancer	RCT: 1 Controlled trial: 5	607	Critically low
Marta et al, 2015²⁶	SRM	January 2015	To assess the effectiveness and safety of induction chemotherapy prior to surgery for untreated OSCC patients	RCT: 2	451	Critically low
Pang et al, 2016²⁷	SRM	September 2016	To compare the prognoses outcomes of mandibular preservation method and the mandibulotomy approach in oral and oropharyngeal cancer patients	Cohort: 6	309	Critically low
Tang and Leung, 2016²⁸	SR	February 2015	To answer the clinical question, “When should elective neck dissection be performed in maxillary gingival and alveolar squamous cell carcinoma with negative neck nodes?”	Cohort: 10	506	Critically low
Wang et al, 2018²⁹	SRM	March 2017	To perform a meta-analysis to compare discontinuous neck dissection with incontinuity neck dissection as a treatment modality for SCC of the tongue and floor of the mouth	Cohort: 8	796	Critically low

Abbreviations: AMSTAR-2, Assessing the Methodological Quality of Systematic Reviews-2; OSCC, oral squamous cell carcinoma; RCT, randomized controlled trial; SCC, squamous cell carcinoma; SR, systematic review; SRM: systematic review with meta-analysis.