The HIV Medication Taking Self-efficacy Scale: psychometric evaluation.
OBJECTIVE
This paper is a report of an examination of the psychometric properties of the HIV Medication Taking Self-efficacy Scale.


BACKGROUND
Self-efficacy is a critically important component of strategies to improve HIV medication-taking; however, valid and reliable tools for assessing HIV medication-taking self-efficacy are limited.


METHODS
We used a cross-sectional, correlational design. Between 2003 and 2007, 326 participants were recruited from sites in Pennsylvania and Ohio in the United States of America. Six self-report questionnaires administered at baseline and 12 weeks later during 'Improving Adherence to Antiretroviral Therapy' were used to examine the variables of interest. Means and variances, reliability, criterion, and construct validity of the HIV Medication Taking Self-efficacy Scale were assessed.


RESULTS
Participants reported high self-confidence in their ability to carry out specific medication-related tasks (mean = 8·31) and in the medication's ability to effect good outcomes (mean = 8·56). The HIV Medication Taking Self-efficacy Scale and subscales showed excellent reliability (α = 0·93∼0·94). Criterion validity was well-established by examining the relationships between the HIV Medication Taking Self-efficacy Scale and selected physiological and psychological factors, and self-reported medication adherence (r = -0·20∼0·58). A two-factor model with a correlation between self-efficacy belief and outcome expectancy fitted the data well (model χ(2) = 3871·95, d.f. = 325, P < 001; CFA = 0·96; RMSEA = 0·046).


CONCLUSIONS
The HIV Medication Taking Self-efficacy Scale is a psychometrically sound measure of medication-taking self-efficacy for use by researchers and clinicians with people with HIV. The findings offer insight into the development of interventions to promote self-efficacy and medication adherence in persons with HIV.
Erlen
Judith A
JA
School of Nursing, University of Pittsburgh, Pennsylvania, USA. jae001@pitt.edu
Cha
Eun Seok
ES
Kim
Kevin H
KH
Caruthers
Donna
D
Sereika
Susan M
SM
D000293:Adolescent; D000328:Adult; D044966:Anti-Retroviral Agents / Q000008:administration & dosage*; D003430:Cross-Sectional Studies; D005163:Factor Analysis, Statistical; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000523:psychology; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D015404:Nursing Methodology Research; D011594:Psychometrics; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D058028:Research Report; D012196:Review Literature as Topic; D012646:Self Administration / Q000523:psychology*; D020377:Self Efficacy; D011795:Surveys and Questionnaires / Q000592:standards*; D014481:United States; D055815:Young Adult
D044966:Anti-Retroviral Agents