Table 1. Baseline characteristics of studies included in the meta-analysis*.
| First Author (reference) | Year Pub | Country | Age | Underlying Condition | Setting | No. Rando-mized | Type of Laser | Wave-length (nm) | Power Output (mW) | Irradiation Time per Spot (sec) | Energy per Spot (Joules) | Energy Density (J/cm2) | Laser Schedule | Oral Mucositis Evaluation Schedule | Mucositis Assessment Scale |
| Antunes [14], [36] | 2013 | Brazil | Adults | Head and neck cancer | Chemo-radio | 94 | InGaAIP | 660 | 100 | 10 | 1 | 4 | 5 sessions/week during radiation | Daily | WHO and OMAS |
| Arbabi-Kalati [15] | 2013 | Iran | Adults | Oncologic disorders | Chemo | 48 | Mustang | 630 | 30 | NA | NA | 5 | Prior to chemotherapy | Two times/week | WHO |
| Gautam [16], [37] | 2012 | India | Adults | Head and neck cancer | Chemo-radio | 239 | He-Ne | 632.8 | 24 | 125 | 3 | 3 | 5 sessions/week×45 days | Weekly | RTOG/EORTC |
| Gautam [17] | 2012 | India | Adults | Oral carcinoma | Chemo-radio | 121 | He-Ne | 632.8 | 24 | 145 | 3.5 | 3.5 | 5 sessions/week during radiation | Weekly | RTOG/EORTC |
| Gouvea de Lima [18] | 2012 | Brazil | Adults | Head and neck cancer | Chemo-radio | 75 | GaAlAs | 660 | 10 | 10 | 0.1 | 2.5 | 5 sessions/week during radiation | Every two weeks | NCI CTCv2 |
| Hodgson (a) [19] | 2012 | USA | Both | Hematologic, oncologic disorders | HSCT (allo, auto) | 40 | Infrared LED | 670±10 | 50 | 80 | 4 | 4 | Daily from day 0 to day +14 | Three times/week | WHO,NCI CTCAE and OMAS |
| Hodgson (b) [19] | 2012 | USA | Adults | Multiple myeloma | HSCT (auto) | 40 | Infrared LED | 670±10 | 50 | 80 | 4 | 4 | Daily from day 0 to day +14 | Three times/week | WHO,NCI CTCAE and OMAS |
| Oton-Leite [20], [48] | 2012 | Brazil | Adults | Head and neck cancer | Radio or Chemo-radio | 60 | InGaAlP | 685 | 35 | 25 | 0.8 | 2 | 5 sessions/week during radiation | Mid and at the end of treatment (week 3 and week 6) | WHO |
| Pires-Santos [38] | 2012 | Brazil | Adults | Breast cancer | Chemo | 12 | NA | NA | NA | NA | NA | NA | Day 0 to day +7 q 48 hours | NA | NA |
| Silva [21] | 2011 | Brazil | Both | Hematologic, oncologic disorders | HSCT (allo, auto) | 42 | InGaAIP | 660 | 40 | 4 | 0.16 | 4 | Daily from day −4 to day +4 | Daily | WHO |
| Chor [39] | 2010 | Brazil | Adults | NA | HSCT (auto) | 34 | AsGaAl | 660 | 50 | NA | NA | NA | Daily from day −7 to day 0 | Daily | Tardieu |
| Khouri [47] | 2009 | Brazil | Both | Hematologic disorders | HSCT (allo) | 22 | InGaAIP and GaAlAs | 660 and 780 | 25 | 10 | 0.25 | 6.3 | Daily until day +15 or day of engraftment | NA | WHO and OMAS |
| Antunes [40] | 2007 | Brazil | Adults | Hematologic Disorders | HSCT (allo, auto) | 38 | InGaAIP | 660 | 46.7 | 16.7 | 0.8 | 4 | Daily from day −7 until neutrophil recovery | Daily | WHO and OMAS |
| Cruz [41] | 2007 | Brazil | Children | Hematologic and solid malignancies | Chemo or HSCT (auto) | 62 | NA | 780 | 60 | NA | NA | 4 | Daily from start of chemo×5 days | Day +8 and day +15 | NCI CTC |
| Schubert [42] | 2007 | USA | Both | Hematologic, oncologic disorders | HSCT (allo, auto) | 47 | GaAlAs | 650 | 40 | 2 | 0.08 | 2 | Daily from day −1 of conditioning to day +2 | Two times/week | OMI [55] |
| Arun Maiya [35] | 2006 | India | Adults | Oral carcinoma | Radio | 50 | He-Ne | 632.8 | 10 | 180 | 1.8 | 1.8 | 5 sessions/week during radiation | Once at the end of treatment (week 6) | WHO |
| Lopes [43] | 2006 | Brazil | Adults | Head and neck cancer | Chemo-radio | 60 | InGaAlP | 685 | 35 | 58 | 2 | 2 | NA | Pretreatment, 4 weeks and at the end of therapy | NCI CTC |
| Bensadoun [44], [45] | 1999 | France | Adults | Head and neck cancer | Radio | 30 | He-Ne | 632.8 | 60 | 33 | 2 | 2 | 5 sessions/week during radiation | Weekly | WHO |
| Cowen [46] | 1997 | France | Adults | Hematologic malignancies | HSCT (auto) | 30 | He-Ne | 632.8 | 60 | 10 | 0.6 | 1.5 | Daily from day −5 to day −1 | Daily | Tardieu |
Abbreviations: Allo - allogeneic hematopoietic stem cell transplant; Auto-autologous hematopoietic stem cell transplant; Chemo – chemotherapy; EORTC-European Organization for Research and Treatment of Cancer; GaAIAs/AsGaAI – gallium-aluminium-arsenide/arsenate; He-Ne- helium-neon; HSCT – hematopoietic stem cell transplantation; InGaAIP – indium-gallium-aluminium phosphide; LED – light emitting diode; NA – not available; NCI CTC – National Cancer Institute Common Terminology Criteria; OMAS – Oral Mucositis Assessment Scale; OMI - Oral Mucositis Index; Pub – published; Radio- radiotherapy; RTOG – Radiation Therapy Oncology Group; VAS – visual analog scale; WHO – World Health Organization.
*There were 18 studies reporting 19 separate comparisons between low level light therapy and placebo/no therapy as one study stratified the population by underlying disease diagnosis and HSCT regimen.