title: Comparing Prospectively Recorded Posttraumatic Amnesia Duration With Retrospective Accounts.
abstract: OBJECTIVE
  Limited research has been conducted comparing different methods for determining the duration of posttraumatic amnesia (PTA). This study compared prospectively recorded PTA duration (P-PTA) with retrospective reports of the return of continuous memory (R-PTA).
  
  
  METHODS
  Fifty-nine individuals admitted to a head injury rehabilitation unit with a traumatic brain injury who had their PTA duration recorded using the Westmead Post-Traumatic Amnesia Scale. Participants were between 6 months and 6 years postinjury at the time of study.
  
  
  METHODS
  P-PTA was determined on the basis of Westmead Post-Traumatic Amnesia Scale responses. R-PTA was ascertained using a semistructured telephone interview.
  
  
  RESULTS
  Although the PTA measures were significantly positively correlated (r = 0.76), mean R-PTA was significantly longer than mean P-PTA. In 34 cases (57.6%), R-PTA was longer than P-PTA (13 participants moved to a higher injury severity band), and in 22 cases (37.3%), R-PTA was shorter than P-PTA (8 participants moved to a lower injury severity band). The difference between P-PTA and R-PTA was not significantly associated with age, Glasgow Coma Scale score, overall PTA duration, or the number of days postinjury of the retrospective interview.
  
  
  CONCLUSIONS
  Prospective and retrospective estimates of PTA duration were not comparable within the present sample. Further research comparing the two methods is needed.
authors.affiliation: School of Psychological Sciences, Monash University, Clayton, Victoria, Australia; and Monash-Epworth Rehabilitation Research Centre, Epworth Hospital, Richmond, Victoria, Australia.
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Roberts
authors.forename: Gershon
authors.initials: G
authors.lastname: Spitz
authors.forename: Jennie L
authors.initials: JL
authors.lastname: Ponsford
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000647:Amnesia / Q000209:etiology*; D000070642:Brain Injuries, Traumatic / Q000523:psychology*; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020127:Recovery of Function; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult