title: A systematic review of time to diagnosis in children and young adults with cancer.
abstract: OBJECTIVE
  It is often assumed that prolonged time to diagnosis (TTD) for cancer negatively influences overall survival and survivorship through advanced stage disease at diagnosis. This systematic review assesses existing early diagnosis research in childhood and young adult cancer and aims to identify whether a consensus exists within the literature in relation to the terminology and methodologies used to investigate TTD in this population.
  
  
  METHODS
  Medline, Embase, the Centre for Reviews and Dissemination database and Cochrane library were searched for papers on children and young adults (0-30 years) published from 1948 to the present.
  
  
  RESULTS
  Of the 1665 potentially eligible citations identified, 32 papers met the inclusion criteria. The majority of work was in European (n=15) or North American (n=8) populations. Most work focused on brain tumours (n=10), retinoblastomas (n=5) and bone and soft tissue sarcomas (n=4). The majority of studies were in hospital-based settings (n=25), with only seven papers adopting a population-based setting. Summary statistics presented were mostly median TTD, the skewed distribution of the data meant comparisons between studies based on medians were difficult and combining studies within a meta-analysis was not appropriate.
  
  
  CONCLUSIONS
  Within the childhood and young adult population, TTD for cancer varies between diagnostic groups and with age at diagnosis in the majority of studies. In order that clear conclusions can be drawn from early diagnosis research in children and young adults, specific criteria identifying circumstances in which delay has occurred should accompany a defined time line to diagnosis or treatment in every study.
authors.affiliation: Yorkshire Regional Centre for Paediatric Oncology and Haematology, Leeds General Infirmary, Leeds, Yorkshire, UK. ugm0cdl@leeds.ac.uk
authors.forename: Christopher David
authors.initials: CD
authors.lastname: Lethaby
authors.forename: Susan
authors.initials: S
authors.lastname: Picton
authors.forename: Sally E
authors.initials: SE
authors.lastname: Kinsey
authors.forename: R
authors.initials: R
authors.lastname: Phillips
authors.forename: Marlous
authors.initials: M
authors.lastname: van Laar
authors.forename: Richard G
authors.initials: RG
authors.lastname: Feltbower
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D042241:Early Diagnosis; D006801:Humans; D009369:Neoplasms / Q000175:diagnosis*; D011379:Prognosis; D013997:Time Factors; D055815:Young Adult