Published English-language literature
PBM research statistics
Source: PBM Database statistics, WALT 2026 presentation and the updated PBM indications workbook. The workbook contains 293 indication rows; overlapping labels are grouped in the directory.
Publication growth and research locations
Photobiomodulation research over time
Each bar shows the running publication-record total through that year. Its segments show the countries recorded in the database.
- Brazil2,224 records
- United States935 records
- China758 records
- Iran662 records
- Korea346 records
- Italy342 records
- Turkey315 records
- Japan293 records
- India253 records
- Other / unreported3,065 records
PBM Database snapshot: 25 September 2026. Eleven records dated before 1980 and three without a usable year are outside this timeline. Country groups use the first country listed in the database; “Other / unreported” combines remaining entries and records without a country.
Countries represented
Publication counts by country
Counts for the 30 most represented single-country groups are shown below. The remainder is split into other countries, multinational entries and records with an unverified country.
The 30 named groups total 8,927 records; 604 are from other countries, 203 are multinational and 107 have an unverified country (9,841 total).
PBM Database checked 16 October 2026 · Sunlight excluded. Counts reflect database records, not deduplicated publications. Multinational entries name multiple countries or are marked international. Country unverified includes blank, placeholder and unresolved entries; limited full-text access may prevent confirmation.
Study models
Publications by study model
The database groups publications as human research, animal experiments or in-vitro research.
Human studies
clinical and human research
Animal experiments
preclinical research
In-vitro studies
cellular and laboratory research
- Dermal fibroblasts
- Keratinocytes
- Osteoblasts
- Adipose-derived stem cells
- Neurons
- Astrocytes
- Gingival fibroblasts
- Dental pulp stem cells
- Myoblasts
- Endothelial cells
- Macrophages
- Chondrocytes
- Mesenchymal stem cells
- Schwann cells
- Microglia
- Cardiomyocytes
- Osteoclasts
- Monocytes
- Periodontal ligament stem cells
- Adipocytes
- Myotubes
- Neural stem cells
- Smooth muscle cells
- Lymphocytes
- Odontoblasts
- Hepatocytes
- Melanocytes
- Umbilical cord MSCs
- Dermal papilla cells
- Neutrophils
- Retinal pigment epithelial cells
- Erythrocytes
- Spermatozoa
- HaCaT
- SH-SY5Y
- PC12
- C2C12
- RAW 264.7
- MC3T3-E1
- MCF-7
- HeLa
Selected examples from PBM Database in-vitro records.
Review literature
Reviews in the database
Meta-analyses are included within the systematic-review count.
Cumulative overview
Publications over time
Each year shows the cumulative number of dated records through that year.
Cell shading shows each row’s share of its final total. Human design rows are nested subsets. Systematic reviews include meta-analyses, shown again as a subset. Sham-controlled includes records labelled “sham-controlled”, “double-blind” or “triple-blind”.
PBM Database snapshot, 4 October 2026 · 9,836 dated records · Sunlight excluded · 2026 incomplete
Research publication venues
PBM research appears in high-impact journals
Examples across different kinds of research
- Randomized clinical trial of PBM for Bothrops atrox snakebiteJAMA Internal Medicine · 2024 · human clinical research↗
- Noninvasive low-level laser therapy for thrombocytopeniaScience Translational Medicine · 2016 · mouse research↗
- Randomized red-light trial for myopiaJAMA Ophthalmology · 2024 · human clinical research↗
- Low-level laser therapy for neck pain: systematic review and meta-analysisThe Lancet · 2009 · systematic review and meta-analysis↗
- Low-power laser for oral mucositis after bone marrow transplantation: randomized trialBlood · 2007 · human randomized trial↗
- Low-intensity laser therapy for painful diabetic neuropathy: controlled trialDiabetes Care · 2004 · sham-controlled randomized trial↗
- Photobiomodulation for methanol-induced retinal toxicityProceedings of the National Academy of Sciences · 2003 · rat model↗
- Low-energy laser irradiation after myocardial infarctionCirculation · 2001 · rat and dog models↗
- Transcranial low-level light therapy after moderate traumatic brain injuryJAMA Network Open · 2020 · randomized human trial↗
- Microglia modulation with 1070-nm light in an Alzheimer’s disease mouse modelLight: Science & Applications · 2021 · animal research↗
- Wearable NIR OLED phototherapy platform for hair-loss researchNature Communications · 2026 · device and cell research↗
- Photobiomodulation for dry age-related macular degeneration: 12-month trialBritish Journal of Ophthalmology · 2026 · multicentre clinical trial↗
- Arterial-wall photoremodeling after angioplastyJournal of the American College of Cardiology · 1998 · atherosclerotic rabbit model↗
- Near-infrared light in a monkey model of Parkinson diseaseAnnals of Neurology · 2016 · monkey model↗
- Laser therapy for activated Achilles tendinitis: placebo-controlled trialBritish Journal of Sports Medicine · 2006 · human randomized trial↗
- Laser therapy for postmastectomy lymphedema: placebo-controlled trialCancer · 2003 · human randomized trial↗
PBM Database journal counts
Which journals appear most often in the database?
This frequency ranking reflects journal names in database records.
- Lasers in Medical Science1,424
- Photobiomodulation, Photomedicine, and Laser Surgery900
- Lasers in Surgery and Medicine329
- Journal of Photochemistry and Photobiology B311
- Journal of Lasers in Medical Sciences252
- Laser Therapy208
- Journal of Biophotonics173
- Photochemistry and Photobiology161
- Scientific Reports129
- Photodiagnosis and Photodynamic Therapy117
Counts are journal-name entries in 10,025 PBM Database records with a journal listed (data checked 26 September 2026). “Photomed Laser Surg” and “Photobiomodul Photomed Laser Surg” are combined under the journal’s current title. Counts describe database records, not journal quality or evidence strength.
PBM Database details
Research models, treatment parameters and topic growth
Human study sample sizes
Numerical sample sizes appear in 2,931 of 3,341 human-research records. Median recorded sample size: 36.
Human study treatment durations
A classifiable treatment duration is recorded in 1,978 of 3,342 human-research records (59.2%). Bars show the distribution among those 1,978 records.
Source: PBM Database, checked 17 October 2026; publication records, not deduplicated trials. Durations are approximate: 4 weeks ≈ 1 month, 8 weeks ≈ 2 months and 12 weeks ≈ 3 months. A single session or a course lasting up to 24 hours counts as 1 day. We use explicit course lengths from “N sessions” or a treatment duration labelled in Study type. The ≥24-month group counts source-verified publications: a qualifying exposure in at least one treatment arm or case is counted once per publication; some records have mixed durations and cohort publications may overlap. Follow-up and data-collection periods, frequency alone, uncertain courses and unverified ranges are not treated as PBM exposure.
LIGHT PARAMETERS
Wavelengths recorded
405–590 nm
Violet to amber302 records
- 405 nm47
- 450 nm42
- 470 nm47
- 532 nm61
- 590 nm59
625–640 nm
Red1,181 records
- 625 nm38
- 630 nm259
- 633 nm544
- 635 nm220
- 640 nm80
650–690 nm
Red1,940 records
- 650 nm278
- 655 nm53
- 660 nm1,199
- 670 nm295
- 685 nm73
780–810 nm
Near-infrared1,753 records
- 780 nm295
- 800 nm31
- 808 nm795
- 810 nm619
820–850 nm
Near-infrared1,062 records
- 820 nm64
- 830 nm657
- 850 nm326
870–910 nm
Near-infrared642 records
- 875 nm40
- 880 nm66
- 890 nm110
- 904 nm296
- 905 nm130
940–980 nm
Near-infrared542 records
- 940 nm208
- 950 nm40
- 970 nm47
- 980 nm252
1064–1072 nm
Near-infrared256 records
- 1064 nm240
Database snapshot: 25 September 2026.
625–640 nm
Red1,181 records
- 625 nm38
- 630 nm259
- 632 nm25
- 633 nm544
- 635 nm220
- 637 nm22
- 640 nm80
650–690 nm
Red1,940 records
- 650 nm278
- 655 nm53
- 658 nm35
- 660 nm1,199
- 670 nm295
- 680 nm22
- 685 nm73
- 690 nm9
780–810 nm
Near-infrared1,753 records
- 780 nm295
- 790 nm20
- 800 nm31
- 808 nm795
- 810 nm619
820–850 nm
Near-infrared1,062 records
- 820 nm64
- 825 nm24
- 830 nm657
- 850 nm326
870–910 nm
Near-infrared642 records
- 870 nm21
- 875 nm40
- 880 nm66
- 890 nm110
- 904 nm296
- 905 nm130
- 910 nm23
940–980 nm
Near-infrared542 records
- 940 nm208
- 950 nm40
- 970 nm47
- 980 nm252
1064–1072 nm
Near-infrared256 records
- 1064 nm240
- 1070 nm7
- 1072 nm9
Database snapshot: 25 September 2026; Sunlight records excluded. Group totals count each record once across the wavelengths shown in that group. Individual wavelength counts may overlap. Bars share one scale. All exact values appearing in at least 20 records between 400 and 1100 nm are included above, with 690, 1070 and 1072 nm also shown.
TREATMENT PARAMETERS
Recorded energy density
Human
n = 1,096 recordsRat
n = 676 recordsMouse
n = 207 recordsRabbit
n = 54 recordsIn vitro
n = 326 recordsDatabase snapshot: 25 September 2026.
Topics with more records in recent years
Citation ranking · broad literature search
20 highly cited PBM papers
- 01
Proposed Mechanisms of Photobiomodulation or Low-Level Light Therapy
Lucas Freitas de Freitas, Michael R. Hamblin
1,6402016 - 02
Primary and secondary mechanisms of action of visible to near-IR radiation on cells
Tiina I. Karu
1,3851999 - 03
Mechanisms and applications of the anti-inflammatory effects of photobiomodulation
Michael R. Hamblin
1,2682017 - 04
Mechanisms and Mitochondrial Redox Signaling in Photobiomodulation
Michael R. Hamblin
8262017 - 05
Photobiomodulation: Underlying Mechanism and Clinical Applications
Claudia Dompé, Lisa Moncrieff, Jacek Matys, et al.
7942020 - 06
Photobiology of low-power laser effects
Tiina Karu
7491989 - 07
Low-Level Light/Laser Therapy Versus Photobiomodulation Therapy
Juanita J. Anders, Raymond J. Lanzafame, Praveen R. Arany
6622015 - 08
Shining light on the head: Photobiomodulation for brain disorders
Michael R. Hamblin
6412016 - 09
Photobiomodulation directly benefits primary neurons functionally inactivated by toxins: role of cytochrome c oxidase
Margaret T. T. Wong-Riley, Huan Ling Liang, Janis T. Eells, et al.
6332005 - 10
Exact Action Spectra for Cellular Responses Relevant to Phototherapy
Tiina I. Karu, Sergei F. Kolyakov
6162005
- 11
Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised placebo or active-treatment controlled trials
Roberta T. Chow, Mark I. Johnson, Rodrigo Álvaro Brandão Lopes-Martins, et al.
6152009 - 12
A systematic review of low level laser therapy with location-specific doses for pain from chronic joint disorders
Jan Magnus Bjordal, Christian Couppé, Roberta T. Chow, et al.
5862003 - 13
Low-level laser therapy in acute pain: a systematic review of possible mechanisms of action and clinical effects in randomized placebo-controlled trials
Jan Magnus Bjordal, Mark I. Johnson, Vegard Vereide Iversen, et al.
5862006 - 14
Low-level laser therapy: a useful technique for enhancing the proliferation of various cultured cells
Khalid M. AlGhamdi, Ashok Kumar, Noura A. Moussa
5792011 - 15
Mitochondrial Signaling in Mammalian Cells Activated by Red and Near-IR Radiation
Tiina I. Karu
5572008 - 16
Brain Photobiomodulation Therapy: a Narrative Review
Farzad Salehpour, Javad Mahmoudi, Farzin Kamari, et al.
5352018 - 17
Low-level laser therapy activates NF-kB via generation of reactive oxygen species in mouse embryonic fibroblasts
Aaron C.-H. Chen, Praveen R. Arany, Ying-Ying Huang, et al.
5252011 - 18
Molecular mechanisms of cell proliferation induced by low power laser irradiation
Xuejuan Gao, Da Xing
5052009 - 19
Low-level laser therapy for wound healing: mechanism and efficacy
William Posten, David A. Wrone, Jeffrey S. Dover, et al.
4902006 - 20
Mechanisms of low level light therapy
Michael R. Hamblin, Tatiana N. Demidova
4782006
Publication ranking · PBM database
50 most prolific PBM researchers
- 01Michael R Hamblin(United Kingdom)181
- 02Sandra Kalil Bussadori(Brazil)132
- 03Ernesto Cesar Pinto Leal-Junior(Brazil)120
- 04115
- 05Raquel Agnelli Mesquita-Ferrari(Brazil)114
- 06Mohammad Bayat(Iran)103
- 07Heidi Abrahamse(South Africa)99
- 08Nivaldo Antonio Parizotto(Brazil)93
- 09Reza Fekrazad(Iran)79
- 10Rodrigo Álvaro Brandão Lopes-Martins(Brazil)77
- 1174
- 12Praveen R Arany(United States)74
- 1366
- 14Antonio Luiz Barbosa Pinheiro(Brazil)66
- 15Jan Magnus Bjordal(Norway)64
- 16Ana Claudia Muniz Renno(Brazil)61
- 17Rodrigo Labat Marcos(Brazil)60
- 18John Mitrofanis(Australia)56
- 19Nicolette N Houreld(South Africa)55
- 20Sufan Chien(United States)55
- 21Abdollah Amini(Iran)54
- 22Lara Jansiski Motta(Brazil)54
- 23Shaiane Silva Tomazoni(Brazil)52
- 24Márcia Martins Marques(Brazil)50
- 25Vanderlei Salvador Bagnato(Brazil)49
- 26F Gonzalez-Lima(United States)47
- 27Manoela Domingues Martins(Brazil)47
- 28Cleber Ferraresi(Brazil)45
- 29Stefano Benedicenti(Italy)45
- 30Andrey Jorge Serra(Brazil)42
- 31Paolo Cassano(United States)41
- 32Jin-Chul Ahn(South Korea)38
- 33Regiane Albertini(Brazil)38
- 34Alyne Simões(Brazil)37
- 35Andrea Amaroli(Italy)37
- 36René-Jean Bensadoun(France)37
- 37Adenilson de Souza da Fonseca(Brazil)36
- 38Phil-Sang Chung(South Korea)36
- 39Jared Jagdeo(United States)35
- 40Lucio Frigo(Brazil)35
- 41Maria Cristina Chavantes(Brazil)35
- 42Stella Regina Zamuner(Brazil)35
- 43Juanita J Anders(United States)34
- 44Carlos de Paula Eduardo(Brazil)33
- 4533
- 46Lívia Assis(Brazil)33
- 4733
- 48Da Xing(China)32
- 49Flávio Aimbire(Brazil)32
- 50Hanli Liu(United States)32
Counts are unique articles in the PBM database; Sunlight records are excluded. Different name forms were merged only when their ORCID and name forms agreed. Countries are inferred from author affiliations; the #1 researcher’s country label is based on public interview information.
PBM Database details
What the published records cover
The analyses below omit the separate “Sunlight” category and use the database snapshot dated 25 September 2026.
Most represented research topics
Ranked by topic labels in the database. Broad record types such as reviews, editorials and protocols are excluded.
| Database topic | Records | Human | Animal | In vitro |
|---|---|---|---|---|
| 01Oral mucositis | 262 | 149 | 23 | 3 |
| 02Bone repair | 209 | 0 | 191 | 7 |
| 03Tooth extraction | 163 | 116 | 24 | 0 |
| 04Orthodontics: Tooth movement | 160 | 76 | 41 | 3 |
| 05TMD | 159 | 108 | 12 | 1 |
| 06Myopia | 154 | 82 | 9 | 2 |
| 07Alzheimer’s disease | 134 | 24 | 53 | 24 |
| 08Excision (secondary intention) | 129 | 0 | 128 | 5 |
| 09Periodontium (in vitro) | 113 | 0 | 1 | 108 |
| 10Tumor cells | 112 | 1 | 2 | 109 |
Study-model counts can overlap when a record includes more than one model; records without these model labels remain in the total.
Publication size ranking
Largest clinical publications by sample size
Examples of the largest patient, participant or case counts recorded in the database.
- 01Diode-laser pain attenuationShiroto · 1989 · Retrospective survey3,635patients
- 02Red-light treatment for myopiaChen · 2026 · Prospective multicentre cohort2,825patients
- 03LLLT for androgenetic alopeciaQiu · 2022 · Real-world observational study1,383patients
- 04904 nm laser for osteoarticular painSoriano · 1995 · Clinical case series938patients
- 05LED photomodulation clinical experienceWeiss · 2005 · Clinical experience900patients
- 06PBM for oral mucositisPaiva · 2024 · Retrospective cohort751patients
- 07LLLT for female infertilityOhshiro · 2012 · Extended clinical case series701patients
- 08Laser-assisted liposculptureNeira & Ortiz-Neira · 2002 · Clinical case series700cases
- 09PBM after hematopoietic cell transplantationBezinelli · 2021 · 15-year retrospective study693patients
- 10Transcranial laser for acute strokeZivin · 2009 · Double-blind randomized trial660patients
Patient, participant and case counts only; treatment-unit counts such as teeth are excluded. Cohort overlap is not deduplicated.
One field, many names
Terminology
Photobiomodulation
Low-level laser therapy
used in light therapy
PBM / photo-
11- Photobiomodulation
- Photobioactivation
- Photobiostimulation (PBM therapy)
- Photo-enhancement
- Photoradiation
- Photostimulation
- Therapeutic photobiomodulation
- Photomodulation
- Photobiotherapy
- Photobiological modulation
- Photoregulation of cellular metabolism
Low-level / low-power
22- Low-level laser therapy
- High fluence low-power laser irradiation
- Low dose laser irradiation
- Low-energy Helium-Neon laser irradiation
- Low-energy laser irradiation
- Low energy light irradiation
- Low-intensity laser irradiation (LILI)
- Low-intensity laser therapy
- Low-level laser
- Low-level laser energy
- Low-level light
- Low-level light therapy
- Low-power laser therapy
- Low-power diode laser
- Low-power laser irradiation (LPLI)
- Low-power laser stimulation
- Low-power laser treatment
- Low power red laser light (LPRLL)
- Low-level phototherapy
- Low reactive-level laser therapy
- Low-intensity light therapy
- Low-energy photon therapy (LEPT)
Wavelengths
16- 660nm LED light source
- 670nm light
- λ780 nm laser light
- 830nm laser
- 810-nm diode laser
- Far-red light
- Far red/near infrared light
- Laser 904 nm
- Near infra-red
- Near-infrared light
- Near-infrared light treatment
- Water-filtered infrared-A
- Red light therapy (RLT)
- Polychromatic light
- Monochromatic infrared energy (MIRE)
- Monochromatic infrared photoenergy (MIPE)
Laser descriptors
17- CLASS IV laser therapy
- Cold laser
- Cold laser therapy (CLT)
- Helium-neon laser
- He-Ne laser
- Laser light irradiation
- Laser treatment
- MID-laser therapy
- Physiotherapy laser
- Short pulsed nonablative infrared laser irradiation
- Soft laser
- Laser phototherapy
- Laser biostimulation
- Laser biomodulation
- Multiwave Locked System (MLS) laser therapy
- High-intensity laser therapy (HILT)
- High-power laser therapy (HPLT)
Light / LED
22- Electromagnetic energy
- Irradiation
- LED-based red light photo-stimulation
- LED-light
- LED phototherapy
- Light-emitting diode irradiation
- Light-Emitting Diode Phototherapy
- Monochromatic phototherapy
- Nanoparticle-emitted light
- Narrow-band light
- Narrow-band red light phototherapy
- Polarized light therapy
- Singlet oxygen energy (SOE light)
- Visible light
- Bioptron light therapy
- Polarized polychromatic non-coherent light
- Organic light-emitting diode therapy (OLED)
- LED photomodulation
- Fluorescent light energy (FLE)
- Biophotonic therapy
- Superluminescent diodes (sLED)
- Anodyne light therapy
Applications
14- Intravascular red laser therapy
- Intravascular Low-Power Laser illumination
- Intravascular low-power red laser light
- Laser acupuncture
- Transcranial infrared laser therapy
- Transcranial Laser Stimulation
- Transcranial laser therapy (TLT)
- Transcranial low level laser (light) therapy
- Photoneuromodulation
- Intranasal photobiomodulation
- Transdermal photobiomodulation
- Sublingual laser blood irradiation
- Intravenous laser blood irradiation (ILBI)
- Transcranial infrared laser stimulation (TILS)