title: A meta-analysis of the efficacy of phototherapy in tissue repair.
abstract: OBJECTIVE
  The effect of phototherapy on tissue repair was determined by aggregating the literature and using statistical meta-analysis to analyze pertinent studies published between 2000 and 2007.
  
  
  BACKGROUND
  Phototherapy has been used for more than 40 y; however, its efficacy on tissue repair remains contentious.
  
  
  METHODS
  Related original studies were gathered from every available source. The papers were then screened and coded; those meeting pre-established inclusion criterion were subjected to meta-analysis, using Cohen's d statistic to determine treatment effect size.
  
  
  RESULTS
  Seventy effect sizes were computed from the 23 papers that met the inclusion criteria. The overall mean effect obtained was highly significant, d = +1.94 (95% confidence interval = 0.58-2.50). Further analyses revealed a similarly positive effect of phototherapy on tissue repair in experimental animal studies, d = +2.60, and a small to moderately positive effect in human cases of tissue repair, d = +0.34. The fail-safe number associated with the overall effect was 869; i.e., the number of additional studies in which phototherapy has negative or no effect on wound healing needed to negate the overall large effect size of + 1.94. The corresponding fail-safe numbers for experimental animal and human tissue repair studies were 612 and 64, respectively.
  
  
  CONCLUSIONS
  These findings indicate that phototherapy is a highly effective form of treatment for tissue repair, with stronger supporting evidence resulting from experimental animal studies than human studies.
authors.affiliation: Department of Physical Therapy, School of Health Professions, New York Institute of Technology, Old Westbury, New York, USA.
authors.forename: Andras M
authors.initials: AM
authors.lastname: Fulop
authors.forename: Seema
authors.initials: S
authors.lastname: Dhimmer
authors.forename: James R
authors.initials: JR
authors.lastname: Deluca
authors.forename: David D
authors.initials: DD
authors.lastname: Johanson
authors.forename: Richard V
authors.initials: RV
authors.lastname: Lenz
authors.forename: Keyuri B
authors.initials: KB
authors.lastname: Patel
authors.forename: Peter C
authors.initials: PC
authors.lastname: Douris
authors.forename: Chukuka S
authors.initials: CS
authors.lastname: Enwemeka
mesh_terms: D006801:Humans; D008954:Models, Biological; D010789:Phototherapy; D016896:Treatment Outcome; D014945:Wound Healing / Q000528:radiation effects*