title: Do participants in adjuvant breast cancer trials reflect the breast cancer patient population?
abstract: OBJECTIVE
  To describe the proportion of women in Tayside, Scotland diagnosed with early breast cancer who would have been eligible for influential adjuvant breast cancer trials.
  
  
  METHODS
  Phase III trials of adjuvant treatment for breast cancer referenced in five national guidelines were shortlisted by breast cancer specialists to identify the twelve considered most influential. Eligibility criteria were extracted from protocols and applied to a 16-year cohort of women who had received a diagnosis of breast cancer and the proportion meeting trial criteria calculated. The criteria used clinically in Tayside to make decisions about use of the trial treatments were also applied to the cohort. Finally, the proportion of women receiving adjuvant endocrine therapy as part of their care and who would have been eligible for the trial evaluating that therapy was calculated.
  
  
  RESULTS
  Of the cohort's 4811 women, 3535 (73%) were eligible for at least one trial but eligibility for an individual trial rarely exceeded 45%. There were substantial differences between the proportion of women meeting trial eligibility criteria and the proportion considered clinically eligible for the same treatment. The proportion of women receiving an endocrine therapy as part of their care who would also have been eligible for the trial evaluating that treatment ranged from 17% to 56%.
  
  
  CONCLUSIONS
  Clinical eligibility criteria may be at variance with trial criteria. For adjuvant endocrine therapy, a substantial proportion of women who would have been ineligible for a trial nevertheless received the trial treatment as part of their care.
authors: Health Services Research Unit, University of Aberdeen, AB25 2ZD, UK. Electronic address: streweek@mac.com.
authors: Shaun
authors: S
authors: Treweek
authors: Institute for Research and Innovation in Social Services, Glasgow G1 1UZ, UK. Electronic address: ruth.dryden@iriss.org.uk.
authors: Ruth
authors: R
authors: Dryden
authors: Robertson Centre for Biostatistics, Institute of Health and Wellbeing, University of Glasgow, G12 8QQ, UK. Electronic address: Colin.McCowan@glasgow.ac.uk.
authors: Colin
authors: C
authors: McCowan
authors: Dundee Cancer Centre, University of Dundee, Dundee DD1 9SY, UK. Electronic address: A.Harrow@dundee.ac.uk.
authors: Alison
authors: A
authors: Harrow
authors: Department of Surgical Oncology, MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston Texas 77030, USA. Electronic address: AThompson1@mdanderson.org.
authors: Alastair M
authors: AM
authors: Thompson
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000453:epidemiology* / Q000532:radiotherapy / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D017326:Clinical Trials, Phase III as Topic / Q000706:statistics & numerical data*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D010358:Patient Participation / Q000706:statistics & numerical data; D018579:Patient Selection; D011153:Population; D012606:Scotland / Q000453:epidemiology; D013629:Tamoxifen / Q000627:therapeutic use
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen
keywords: Adjuvant treatment; Applicability; Breast cancer; Generalisabilty; Phase III trials; Record linkage