title: Development of a new diabetes medication self-efficacy scale and its association with both reported problems in using diabetes medications and self-reported adherence.
abstract: BACKGROUND
  Although there are several different general diabetes self-efficacy scales, there is a need to develop a self-efficacy scale that providers can use to assess patient's self-efficacy regarding medication use. The purpose of this study was to: 1) develop a new diabetes medication self-efficacy scale and 2) examine how diabetes medication self-efficacy is associated with patient-reported problems in using diabetes medications and self-reported adherence.
  
  
  METHODS
  Adult English-speaking patients with type 2 diabetes were recruited from a family medicine clinic and a pharmacy in Eastern North Carolina, USA. The patients were eligible if they reported being nonadherent to their diabetes medicines on a visual analog scale. Multivariable regression was used to examine the relationship between self-efficacy and the number of reported diabetes medication problems and adherence.
  
  
  RESULTS
  The diabetes medication self-efficacy scale had strong reliability (Cronbach's alpha =0.86). Among a sample (N=51) of mostly African-American female patients, diabetes medication problems were common (6.1±3.1) and a greater number of diabetes medications were associated with lower medication adherence (odds ratio: 0.35; 95% confidence interval: 0.13, 0.89). Higher medication self-efficacy was significantly related to medication adherence (odds ratio: 1.17; 95% confidence interval: 1.05, 1.30) and inversely related to the number of self-reported medication problems (β=-0.13; P=0.006).
  
  
  CONCLUSIONS
  Higher diabetes medication self-efficacy was associated with fewer patient-reported medication problems and better medication adherence. Assessing medication-specific self-efficacy may help to identify medication-related problems that providers can help the patients address, potentially improving adherence and patient outcomes.
authors.affiliation: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, USA; Cecil G. Sheps Center for Health Services Research, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Betsy
authors.initials: B
authors.lastname: Sleath
authors.affiliation: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Delesha M
authors.initials: DM
authors.lastname: Carpenter
authors.affiliation: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Blalock
authors.affiliation: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Davis
authors.affiliation: Division of Pharmaceutical Outcomes and Policy, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Hickson
authors.affiliation: Polyglot Systems, Inc., Morrisville, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Lee
authors.affiliation: Division of Practice Advancement and Clinical Education, UNC Eshelman School of Pharmacy, Chapel Hill, USA.
authors.forename: Stefanie P
authors.initials: SP
authors.lastname: Ferreri
authors.affiliation: Consortium for Implementation Science, Department of Health Policy and Management, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Scott
authors.affiliation: Department of Family Medicine, Brody School of Medicine, East Carolina University, Greenville, USA.
authors.forename: Lisa B
authors.initials: LB
authors.lastname: Rodebaugh
authors.affiliation: Department of Family Medicine, Brody School of Medicine, East Carolina University, Greenville, USA; Department of Public Health, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
authors.forename: Doyle M
authors.initials: DM
authors.lastname: Cummings
keywords: adherence; diabetes; literacy; self-efficacy