title: Derivation of the Genital Injury Severity Scale (GISS): a concise instrument for description and measurement of external female genital injury after sexual intercourse.
abstract: BACKGROUND
  Inconsistencies abound in the current forensic literature regarding the definition, and as a result, the significance of female genital injury after sexual intercourse. These definitions are based on variables related to the anatomic locations that are examined, the actual physical findings types, and the methods used to detect the findings.
  
  
  OBJECTIVE
  To derive and perform initial clinimetric analyses on a simple instrument that defines, and based on severity, quantifies external genital injury after sexual intercourse. The scale utilizes standard injury definitions and a standardized examination method.
  
  
  METHODS
  After empirical investigation, it was determined that the application of the tool would require the use of magnification and toluidine blue in order to have the sensitivity to detect the majority of injuries that occur after sexual intercourse. Separate matrices were constructed based on anatomic locations and injury types from data collected from sexual assault genital injury examination forms. Principal Components Analyses were applied. A clinical model was constructed from the resultant variables, utilizing operational definitions and forming a template for the instrument.
  
  
  RESULTS
  A twelve-factor instrument measuring five variables along five "types" of severity and two "classes" of severity ensued. The resultant instrument was tested for internal consistency and differential validity. Very good internal consistency was attained (Cronbach's Coefficient α = 0.8). In a pilot study, the scale was able to distinguish a cohort of sexual assault patients from one of consensual intercourse subjects based on type and class of injury (p < 0.0001).
  
  
  CONCLUSIONS
  The findings presented demonstrate that while employing a standardized examination method, the Genital Injury Severity Scale has utility in defining and measuring external genital injury after sexual intercourse.
authors.affiliation: Alameda County Medical Center, Highland, Department of Emergency Medicine, 1411 E. 31st Street, Oakland, CA 94602, USA. dkelly@acmedctr.org
authors.forename: Dana L
authors.initials: DL
authors.lastname: Kelly
authors.forename: Hillary J
authors.initials: HJ
authors.lastname: Larkin
authors.forename: Cecily D
authors.initials: CD
authors.lastname: Cosby
authors.forename: Lauri A
authors.initials: LA
authors.lastname: Paolinetti
mesh_terms: D003075:Coitus; D004396:Coloring Agents; D003127:Colposcopy; D004438:Ecchymosis / Q000145:classification; D004487:Edema / Q000145:classification; D004890:Erythema / Q000145:classification; D005260:Female; D005554:Forensic Medicine; D058869:Gynecological Examination; D006801:Humans; D015601:Injury Severity Score; D022125:Lacerations / Q000145:classification; D025341:Principal Component Analysis; D011902:Rape; D014048:Tolonium Chloride; D014621:Vagina / Q000293:injuries*; D014844:Vulva / Q000293:injuries*
chemical_list: D004396:Coloring Agents; D014048:Tolonium Chloride
keywords: Colposcopy; Consensual intercourse; Genital Injury Severity Scale; Sexual assault; Toluidine blue