The HIV Medication Self-Reported Nonadherence Reasons (SNAR) index and its underlying psychological dimensions

Lena Nilsson Schönnesson, Michael W. Ross, Mark Williams

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


The purpose of this paper is to report on the construction of the HIV Medication Self-Reported Nonadherence Reasons (SNAR) index and its psychological correlates. Data were derived from a sample of 193 Swedish HIV-seropositive women and men receiving antiretroviral medications. Participants who reported dosing and/or scheduling and/or dietary instructions nonadherence in the past 7 days were presented with a modified AACTG list of 18 reasons for nonadherence. From these data, two conceptually and statistically independent factors were obtained, which accounted for 39% of the variance in the data. These factors were used as the basis for constructing two composite measures composing the SNAR index: the Medication concerns scale and the Routine disruption scale. The Medication concerns scale correlated significantly to suboptimal dose and scheduling adherence and Routine disruption scale with poorer dietary instructions adherence. Psychological distress was the best predictor of the SNAR index. The SNAR index has a clearly interpretable factor structure that allows the derived scales to be useful as multi-item measures of self-reported reasons for nonadherence to HIV antiretroviral medications. The psychological factors found to be associated with the index may imply a number of mental-health-related interventions to improve adherence, which deserve further exploration.

Original languageEnglish (US)
Pages (from-to)293-301
Number of pages9
JournalAIDS and Behavior
Issue number3
StatePublished - Sep 2004

Bibliographical note

Funding Information:
The authors would like to extend their gratitude to those women and men who participated in the study for their contribution and the nurses at Gay Men’s Health Center, Söder Hospital and HIV Clinic, Karolinska Hospital for administrating the questionnaires. This study was supported by grants from the Swedish Foundation for Health Care Sciences and Allergy Research; Department of Research, Education, and Development, Stockholm City Council; the Magn Bergvall’s Foundation; and the Swedish Physicians against AIDS Research Foundation, Sweden and from the National Institute on Drug Abuse, USA, R03 DA 12328.


  • HIV
  • adherence
  • coping
  • psychological distress
  • subjective reasons


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