title: Evaluating the evidence: direct-to-consumer screening tests advertised online.
abstract: OBJECTIVE
  Unsupervised online direct-to-consumer (DTC) access to medical services has rapidly expanded to medical screening tests, which have not been critically evaluated for their evidence basis. The objective of this study is to identify the scope of online-advertised DTC screening tests, outline the evidence for use of available DTC testing and suggest regulatory reform to address the relevant issues.
  
  
  METHODS
  An observational study of website advertisements, testing services and counselling/follow-up services for DTC testing was conducted. Data were collected from websites between 4 April and 1 June 2011. Each website was assessed for tests offered, advertised indications and availability of counselling/follow-up services. Advertised testing indications were compared with US Preventive Services Task Force recommendations and/or specialty guidelines and categorized as Supported, Against, Insufficient Evidence or No Guidance.
  
  
  RESULTS
  Of 20 companies identified as offering DTC screening tests, 95% (19/20) do not clearly offer pretest counselling, post-test counselling and/or test follow-up. One hundred and twenty-seven different tests were identified. Only 19/127 (15%) could be Supported for screening in a target group selected for testing; 38/127 (30%) were given recommendations to avoid use in specific target group(s) selected for testing ('Against recommendations'); 29/127 (23%) had Insufficient Evidence of value, and for 64/127 (50%) No Guidance could be given. Only 4/127 (3%) tests were Supported for general screening use.
  
  
  CONCLUSIONS
  Virtually all identified medical tests advertised and offered DTC are not recommended for use in screening by evidence-based guidelines. Limited oversight may lead to inaccurate self-diagnosis, treatment and wasted health resources.
authors.affiliation: Department of Family and Preventive Medicine, University of California, San Diego School of Medicine, San Diego, CA, USA. klovett@ucsd.edu
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: Lovett
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Mackey
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Liang
mesh_terms: D000329:Advertising; D003256:Community Participation; D003376:Counseling; D019317:Evidence-Based Medicine; D005821:Genetic Techniques; D006801:Humans; D007258:Informed Consent; D020407:Internet; D008389:Marketing of Health Services; D008403:Mass Screening / Q000379:methods*; D010353:Patient Education as Topic; D014481:United States