title: Effect of prophylactic low level laser therapy on oral mucositis: a systematic review and meta-analysis.
abstract: BACKGROUND
  Objective was to determine whether prophylactic low level laser therapy (LLLT) reduces the risk of severe mucositis as compared to placebo or no therapy.
  
  
  METHODS
  MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched until February 2014 for randomized controlled trials (RCTs) comparing prophylactic LLLT with placebo or no therapy in patients with cancer or undergoing hematopoietic stem cell transplantation (HSCT). All analyses used random effects models.
  
  
  RESULTS
  Eighteen RCTs (1144 patients) were included. Prophylactic LLLT reduced the overall risk of severe mucositis (risk ratio (RR) 0.37, 95% confidence interval (CI) 0.20 to 0.67; P = 0.001). LLLT also reduced the following outcomes when compared to placebo/no therapy: severe mucositis at the time of anticipated maximal mucositis (RR 0.34, 95% CI 0.20 to 0.59), overall mean grade of mucositis (standardized mean difference -1.49, 95% CI -2.02 to -0.95), duration of severe mucositis (weighted mean difference -5.32, 95% CI -9.45 to -1.19) and incidence of severe pain (RR 0.26, 95% CI 0.18 to 0.37).
  
  
  CONCLUSIONS
  Prophylactic LLLT reduced severe mucositis and pain in patients with cancer and HSCT recipients. Future research should identify the optimal characteristics of LLLT and determine feasibility in the clinical setting.
authors.affiliation: Division of Haematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Sapna
authors.initials: S
authors.lastname: Oberoi
authors.affiliation: Division of Haematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Zamperlini-Netto
authors.affiliation: Program in Child Health Evaluative Sciences, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada; Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Joseph
authors.initials: J
authors.lastname: Beyene
authors.affiliation: Division of Oral Medicine & Dentistry, Brigham and Women's Hospital, Boston, Massachusetts, United States of America.
authors.forename: Nathaniel S
authors.initials: NS
authors.lastname: Treister
authors.affiliation: Division of Haematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada; Program in Child Health Evaluative Sciences, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada.
authors.forename: Lillian
authors.initials: L
authors.lastname: Sung
mesh_terms: D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects; D006801:Humans; D028022:Low-Level Light Therapy / Q000379:methods*; D013280:Stomatitis / Q000209:etiology / Q000517:prevention & control* / Q000628:therapy