title: The basis for monitoring strategies in clinical guidelines: a case study of prostate-specific antigen for monitoring in prostate cancer.
abstract: BACKGROUND
  The volume of published literature on the evaluation and use of tests for monitoring purposes is sparse. Our aim was to determine the extent to which recommendations for monitoring prostate-specific antigen to detect recurrent prostate cancer consider key factors that should inform rule-based strategies for monitoring.
  
  
  METHODS
  We reviewed the recommendations made in clinical guidelines for the repeated measurement of prostate-specific antigen in men who have received primary treatment for localized prostate cancer. We assessed the guidelines using the Appraisal of Guidelines for Research and Evaluation Framework.
  
  
  RESULTS
  We identified guidelines and statements of best practice from nine organizations. We saw considerable inconsistency in recommendations for testing for prostate-specific antigen as a form of monitoring. Recommendations on when to test appeared to be almost exclusively determined using standard follow-up schedules rather than any scientific basis. Recommendations on when to take action were primarily based on consensus statements or retrospective case series. Eight of the nine guidelines acknowledged the potential presence of measurement variability, but they did not attempt to account for the effect of such variability on the interpretation of the results of tests for prostate-specific antigen. Many recommendations were made with few or no supporting references; however, a variety of papers were cited across guidelines. Of 48 papers cited, 29.1% (14/48) were reviews; the remaining 70.8% (34/48) of papers cited were primary studies.
  
  
  CONCLUSIONS
  A systematic approach to the development of monitoring schedules using prostate-specific antigen in guidelines for prostate cancer is lacking, due to inadequacies in the available evidence and its use.
authors.affiliation: Department of Public Health, Epidemiology and Biostatistics, University of Birmingham, Edgbaston, Birmingham, UK. j.dinnes@bham.ac.uk
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Dinnes
authors.forename: Jenny
authors.initials: J
authors.lastname: Hewison
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Altman
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Deeks
mesh_terms: D019317:Evidence-Based Medicine / Q000592:standards; D006801:Humans; D008297:Male; D017410:Practice Guidelines as Topic / Q000592:standards*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis*
chemical_list: D017430:Prostate-Specific Antigen