title: Patient-Centered Outcomes of Medication Adherence Interventions: Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  Using meta-analytic procedures to synthesize changes in patient-centered outcomes after medication adherence interventions.
  
  
  METHODS
  Strategies to locate studies included online searches of 13 databases and 19 research registries, hand searches of 57 journals, and author and ancestry searches of all eligible studies. Search terms included patient compliance, medication adherence, and related terms. Searches were conducted for all studies published since 1960. Eligible published or unpublished primary studies tested medication adherence interventions and reported medication knowledge, quality of life, physical function, and symptom outcomes. Primary study attributes and outcome data were reliably coded. Overall standardized mean differences (SMDs) were analyzed using random-effects models. Dichotomous and continuous moderator analyses and funnel plots were used to explore risks of bias.
  
  
  RESULTS
  Thorough searching located 141 eligible reports. The reports included 176 eligible comparisons between treatment and control subjects across 23,318 subjects. Synthesis across all comparisons yielded statistically significant SMDs for medication knowledge (d = 0.449), quality of life (d = 0.127), physical function (d = 0.142), and symptoms (d = 0.182). The overall SMDs for studies focusing on subsamples of patients with specific illnesses were more modest but also statistically significant. Of specific symptoms analyzed (depression, anxiety, pain, energy/vitality, cardiovascular, and respiratory), only anxiety failed to show a significant improvement after medication adherence interventions. Most SMDs were significantly heterogeneous, and risk of bias analyses suggested links between study quality and SMDs.
  
  
  CONCLUSIONS
  Modest but significant improvements in patient-centered outcomes were observed after medication adherence interventions.
authors.affiliation: School of Nursing, University of Missouri, Columbia, MO, USA. Electronic address: conn@missouri.edu.
authors.forename: Vicki S
authors.initials: VS
authors.lastname: Conn
authors.affiliation: School of Nursing, University of Missouri, Columbia, MO, USA.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Ruppar
authors.affiliation: School of Nursing, University of Missouri, Columbia, MO, USA.
authors.forename: Maithe
authors.initials: M
authors.lastname: Enriquez
authors.affiliation: School of Nursing, University of Missouri, Columbia, MO, USA.
authors.forename: Pamela S
authors.initials: PS
authors.lastname: Cooper
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004347:Drug Interactions; D064420:Drug-Related Side Effects and Adverse Reactions / Q000209:etiology / Q000517:prevention & control; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006304:Health Status; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D010353:Patient Education as Topic; D018802:Patient-Centered Care / Q000191:economics; D011788:Quality of Life; D016896:Treatment Outcome
keywords: anxiety; medication adherence; meta-analysis; patient knowledge; patient-centered outcomes; physical function; quality of life; symptoms