Adherence Self-Efficacy Scale (ASES)

Abstract

The Adherence Self-Efficacy Scale (ASES), often referred to as the HIV-ASES, is a specialized 12-item psychometric instrument designed to quantify an individual’s perceived Self-efficacy regarding adherence to complex HIV treatment regimens. It assesses patient confidence not only in taking Antiretroviral (ART) medication but also in following comprehensive treatment plans, including necessary behavioral changes like nutrition and exercise, particularly when facing significant personal or logistical barriers. Developed initially for use in clinical trials focused on behavioral interventions, the scale is crucial for predicting and monitoring treatment success in the management of chronic conditions.

Keywords

Adherence Self-Efficacy Scale, ASES, HIV-ASES, ART adherence, self-efficacy, treatment adherence, chronic illness management, behavioral intervention, psychometric scale.

Authors

M. O. Johnson, T. B. Neilands, S. E. Dilworth, S. F. Morin, R. H. Remien, M. A. Chesney, Centre for AIDS Prevention Studies (CAPS).

Purpose

The primary purpose of the ASES is to measure the level of confidence (self-efficacy) a patient possesses in their ability to successfully execute complex treatment-related behaviors necessary for effective disease management. This includes strict adherence to prescribed medication schedules (such as ART regimens) and commitment to related health behaviors, including maintaining appropriate nutrition and engaging in regular exercise.

The scale specifically focuses on assessing confidence in the face of anticipated challenges or barriers, such as side effects, disruption to daily routines, feeling discouraged about health status, or dealing with the logistical hassle of clinic appointments. High self-efficacy scores are generally predictive of better adherence outcomes and overall clinical status.

Construct

The ASES is fundamentally designed to operationalize the construct of specific treatment adherence self-efficacy within the context of HIV management. Self-efficacy, as defined by Bandura, refers to an individual’s belief in their capacity to execute behaviors necessary to produce specific performance attainments. In this context, the scale measures confidence related to the maintenance of a demanding medical regimen.

The items target two primary dimensions of adherence behavior: the ability to integrate treatment into daily life smoothly (Adherence Integration) and the resolve to continue treatment despite setbacks or difficulties (Adherence Perseverance). These dimensions capture the psychological resources needed for sustained behavioral commitment essential for managing chronic diseases like HIV.

Validity

The validity of the HIV-ASES was examined through comprehensive psychometrics analysis. Concurrent validity was strongly supported, demonstrating significant relationships between ASES scores and critical clinical and psychosocial variables. Specifically, ASES scores correlated positively with objective measures of ART adherence, improved clinical status (e.g., higher T-cell counts), and reduced healthcare utilization, affirming its utility as a predictive tool for treatment outcomes.

These findings confirm that the scale accurately measures the intended construct—confidence in adherence behaviors—and that this measured confidence is meaningfully associated with real-world health behaviors and clinical benefits for individuals living with HIV.

Reliability

The reliability of the HIV-ASES is robust across multiple measures. Internal consistency, which assesses the homogeneity of the scale items, was demonstrated to be exceptionally strong, with Cronbach’s rho coefficients (ρs) consistently reported above .90.

Furthermore, test-retest reliability was established over significant time intervals. The stability of scores was high at the 3-month follow-up (r coefficients greater than .70) and remained acceptable even at the 15-month follow-up (r coefficients greater than .40). These results indicate that the scale provides highly consistent and stable measures of adherence self-efficacy over time.

Factor Analysis

Factor analyses performed on the HIV-ASES items support a two-factor structure, which conceptually aligns with the multifaceted nature of adherence behavior. These two factors account for a substantial 61% of the total variance observed in the scale items.

• Factor 1: Adherence Integration. This factor reflects the capacity of the individual to seamlessly incorporate the treatment regimen into their existing daily routine. It was associated with a high eigenvalue of 6.12.

• Factor 2: Adherence Perseverance. This factor measures the strength of commitment and resolve to continue treatment despite the presence of difficulties, side effects, or emotional distress. It yielded an eigenvalue of 1.16.

Instrument

Test Type: Self-report Psychometric Scale (Likert-type confidence assessment)

Format: 12 items, utilizing a 10-point response scale where 1 signifies “cannot do it at all” and 10 signifies “certain can do it.”

Language Available: English (Primary validation)

Population Group: Individuals diagnosed with HIV/AIDS requiring complex treatment adherence.

Age Group: Adults (Validation focused on clinical trial participants).

Population Details: Originally validated among participants in clinical trials focusing on behavioral interventions related to stress, coping, and treatment adherence in the HIV treatment population.

Test Methodology: Respondents are asked to rate their confidence regarding their ability to handle specific adherence challenges “in the past month.”

Keywords

HIV, AIDS, Antiretroviral Therapy, medication adherence, self-efficacy measurement, psychological assessment, health behavior, clinical outcomes.

Authors

Author ORCID Identifier: Not provided in source content.

Affiliation Email addresses: Not provided in source content.

Correspondence Address: Correspondence generally directed through the Centre for AIDS Prevention Studies (CAPS) or the primary author, M. O. Johnson.

Permissions & Fee and Test Year

The instrument was first validated and published in 2007 (Johnson et al.). Use of the ASES is permitted for research or educational purposes only and is strictly prohibited for commercial applications. Users are required to cite the primary validation article when utilizing the instrument.

Furthermore, researchers obtaining survey information should acknowledge the University of North Carolina at Chapel Hill Center for AIDS Research (CFAR), NIH funded program P30 AI50410.

Reference’s

• Johnson, M. O., Neilands, T. B., Dilworth, S. E., Morin, S. F., Remien, R. H., & Chesney, M. A. (2007). The role of self-efficacy in HIV treatment adherence: Validation of the HIV treatment adherence self-efficacy scale (HIV-ASES). Journal of Behavioral Medicine, 30(5), 359-370.

• Johnson MO, Neilands TB, Dilworth SE, Morin SF, Remien RH, Chesney MA. The Role of Self-Efficacy in HIV Treatment Adherence: Validation of the HIV Treatment Adherence Self-Efficacy Scale (HIV-ASES). J Behav Med. 2007 Jun 23.

• The scale was developed under the auspices of the Centre for AIDS Prevention Studies (CAPS).

Items of the Adherence Self-Efficacy Scale (ASES)

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

In the past month, how confident have you been that you can:

1. Stick to your treatment plan even when side effects begin to interfere with daily activities?
2. Integrate your treatment into your daily routine?
3. Integrate your treatment into your daily routine even if it means taking medication or doing other things in front of people who don’t know you are HIV-infected?
4. Stick to your treatment schedule even when your daily routine is disrupted?
5. Stick to your treatment schedule when you aren’t feeling well?
6. Stick to your treatment schedule when it means changing your eating habits?
7. Continue with your treatment even if doing so interferes with your daily activities?
8. Continue with the treatment plan your physician prescribed even if your T-cells drop significantly in the next three months?
9. Continue with your treatment even when you are feeling discouraged about your health?
10. Continue with your treatment even when getting to your clinic appointments is a major hassle?
11. Continue with your treatment even when people close to you tell you that they don’t think that it is doing any good?
12. Get something positive out of your participation in treatment, even if the medication you are taking does not improve your health?