title: Impact of non-medical switching on clinical and economic outcomes, resource utilization and medication-taking behavior: a systematic literature review.
abstract: To evaluate current knowledge of the impact of non-medical switching on clinical and economic outcomes, resource utilization and medication-taking behavior.
  
  
  
  The literature was searched (Medline and Web of Science, January 2000-November 2015) to identify United States' studies evaluating ≥25 patients and measuring the impact of non-medical switching of drugs (switching to a chemically distinct but similar medication for reasons other than lack of clinical efficacy/response, side effects or poor adherence) on ≥1 clinical, economic, resource utilization or medication-taking behavior outcome. The direction of association between non-medical switching and outcomes was classified as negative or positive if a statistically significant worsening or improvement was reported, or neutral if no significant difference was observed.
  
  
  
  Twenty-nine studies contributed 96 outcomes (60.4% clinical; 21.9% resource utilization; 13.5% economic; 4.2% medication-taking behavior) within six disease categories (cardio-metabolic, immune-mediated, acid suppression, psychiatric, hormone replacement therapy and pain). The direction of association was more frequently negative (33.3%) or neutral (55.2%) than it was positive (11.5%). Stratified by outcome type, non-medical switching was negatively associated with clinical, economic, healthcare utilization and medication-taking behavior outcomes in 20.7%, 69.2%, 38.1% and 75.0% of cases, respectively; and positively in only 4.8%-17.2% of outcomes subgroups. Of 32 outcomes in patients demonstrating stable/well controlled disease, 68.8% and 31.3% had a negative and neutral direction of association. In patients without demonstrated disease stability, outcomes were negatively, neutrally and positively impacted by non-medical switching in 15.6%, 67.2% and 17.2% of 64 outcomes.
  
  
  
  Our inability to evaluate specific disease state categories and studies/outcomes received equal weight regardless of sample size or magnitude of effect.
  
  
  
  Non-medical switching was more often associated with negative or neutral effects than positive effects on an array of important outcomes. Among patients with stable/well controlled disease, non-medical switching was associated with mostly negative effects.
authors.affiliation: a University of Connecticut School of Pharmacy , Storrs , CT , U.S.A. ;|b Hartford Hospital Evidence-Based Practice Center , Hartford , CT , U.S.A. ;
authors.forename: Elaine
authors.initials: E
authors.lastname: Nguyen
authors.affiliation: a University of Connecticut School of Pharmacy , Storrs , CT , U.S.A. ;|b Hartford Hospital Evidence-Based Practice Center , Hartford , CT , U.S.A. ;
authors.forename: Erin R
authors.initials: ER
authors.lastname: Weeda
authors.affiliation: a University of Connecticut School of Pharmacy , Storrs , CT , U.S.A. ;|b Hartford Hospital Evidence-Based Practice Center , Hartford , CT , U.S.A. ;
authors.forename: Diana M
authors.initials: DM
authors.lastname: Sobieraj
authors.affiliation: c Janssen Scientific Affairs L.L.C. , Raritan , NJ , U.S.A.
authors.forename: Brahim K
authors.initials: BK
authors.lastname: Bookhart
authors.affiliation: c Janssen Scientific Affairs L.L.C. , Raritan , NJ , U.S.A.
authors.forename: Catherine Tak
authors.initials: CT
authors.lastname: Piech
authors.affiliation: a University of Connecticut School of Pharmacy , Storrs , CT , U.S.A. ;|b Hartford Hospital Evidence-Based Practice Center , Hartford , CT , U.S.A. ;
authors.forename: Craig I
authors.initials: CI
authors.lastname: Coleman
mesh_terms: D002318:Cardiovascular Diseases / Q000188:drug therapy; D057915:Drug Substitution / Q000191:economics / Q000706:statistics & numerical data; D015438:Health Behavior; D006801:Humans; D007154:Immune System Diseases / Q000188:drug therapy; D055118:Medication Adherence; D040841:Resource Allocation / Q000191:economics / Q000706:statistics & numerical data; D016896:Treatment Outcome
keywords: Managed care; Non-medical switch; Outcome assessment; Therapeutic interchange