Elsevier

Psychiatry Research

Volume 157, Issues 1–3, 15 January 2008, Pages 259-263
Psychiatry Research

Brief report
Electronic monitoring of antipsychotic medication adherence in outpatients with schizophrenia or schizoaffective disorder: An empirical evaluation of its reliability and predictive validity

https://doi.org/10.1016/j.psychres.2007.05.001Get rights and content

Abstract

This study examined the reliability and predictive validity of electronic monitoring (EM) in assessing the oral antipsychotic medication adherence of outpatients with schizophrenia or schizoaffective disorder. Sixty-one adult outpatients with schizophrenia or schizoaffective disorder who took a single oral antipsychotic medication were assessed monthly over a 6-month study period with EM of medication bottle opening. Symptom severity, as measured by the Positive and Negative Syndrome Scale (PANSS) total score, was assessed monthly over the 6-month study period. Cronbach's coefficient alpha revealed very high internal reliability (α = 0.94). A high degree of test–retest reliability was found (β ranged from 0.75 to 1.19 and r ranged from 0.63 to 0.90). As for predictive validity, greater mean EM adherence was significantly related to lower mean symptom severity.

Introduction

Assessing the medication adherence of outpatients with schizophrenia or schizoaffective disorder is a major challenge. Clinicians generally rely on patients' self-report of adherence. Clinical researchers have used various adherence assessment methods, and each method has its own critical shortcomings (Osterberg and Blaschke, 2005).

Electronic monitoring (EM) has become increasingly used to assess medication adherence in general medical and schizophrenia populations (Byerly et al., 2005a, Byerly et al., 2005b, Diaz et al., 2001, Diaz et al., 2004, Osterberg and Blaschke, 2005). The most commonly employed EM device consists of a medication vial cap that has the same appearance as regular medication bottle caps, but electronically records the date and time of bottle opening. Although EM is increasingly used in outpatients with mental disorders, its reliability and predictive validity have not been fully evaluated in these populations. Accordingly, this study examined the reliability and predictive validity of EM in outpatients with schizophrenia or schizoaffective disorder.

Section snippets

Participants

Sixty-one adult outpatients diagnosed with schizophrenia (n = 35) or schizoaffective disorder (n = 26), as established by the Structured Clinical Interview for DSM-IV, were recruited from three Dallas County public mental health outpatient clinics. Most participants were self-referred from flyers (a few being referred by their treating clinician). Participants were recruited and studied at their usual outpatient clinics. Participants were taking a single oral antipsychotic, and they were at least

Participant characteristics

The study sample included 30 males (49.2%) and 31 females (50.8%), with an average age of 44.3 years, S.D. = 9.1 (range 21–59 years). The average age at illness onset was 23.1 years (S.D. = 10.1). Participants included 40 (65.6%) African Americans, 19 (31.2%) Caucasians, and 2 (3.2%) Hispanics. Twenty-four (39.3%) participants had less than a high school education and 37 (60.7%) had at least a high school education. Forty-three (70.5%) participants did not have a caregiver. The average baseline

Discussion

The current study examined the reliability and predictive validity of EM to assess the oral antipsychotic medication adherence of outpatients with schizophrenia or schizoaffective disorder. The internal reliability of EM to track (over time) oral antipsychotic medication adherence was excellent (α = 0.94 across the entire 6-month study period). The various initial EM assessment periods each had excellent agreement with the subsequent EM assessment periods. Both reliability analyses indicated that

Acknowledgements

This study was supported by NIMH K-Award grant # 5 K23 MH064930, the Stanley Medical Research Institute, the Betty Jo Hay Distinguished Chair in Mental Health, and by a grant from Janssen Medical Affairs, LLC.

References (11)

There are more references available in the full text version of this article.

Cited by (37)

  • Antipsychotic nonadherence measured by electronic adherence monitoring in stabilized chronic schizophrenia: Clinical implications

    2021, Schizophrenia Research
    Citation Excerpt :

    From this perspective, it would be valuable to look at not only studies examining the association of adherence with illness/symptom severity at endpoint but also studies examining the same with illness/symptom severity at baseline. To our knowledge, there have been 6 studies looking at overall adherence and endpoint severity (Acosta et al., 2014, 2013; Brain et al., 2013; Remington et al., 2013, 2007; Yang et al., 2012) and 3 studies looking at adherence and severity at multiple points (Diaz et al., 2001; Nakonezny et al., 2008; Subotnik et al., 2014), respectively; all studies showed that poor adherence was significantly associated with worse illness/symptom severity. However, no study has looked at overall adherence and both baseline and endpoint severity.

  • Digital Biomarkers in Clinical Drug Development

    2019, Handbook of Behavioral Neuroscience
    Citation Excerpt :

    Smart wireless pill bottles can help identify and improve medication adherence. Medication vial cap devices are currently being used by patients in the pharmaceutical and research environments to collect and store all adherence data and have become common practice in general medicine (Byerly et al., 2005; Byerly, Nakonezny, & Lescouflair, 2007; Diaz, Neuse, Sullivan, Pearsall, & Woods, 2004; Nakonezny, Byerly, & Rush, 2008; Osterberg & Blaschke, 2005). The data are also readily accessible to physicians in real time.

  • Measuring adherence to antipsychotic medications for schizophrenia: Concordance and validity among a community sample in rural China

    2018, Schizophrenia Research
    Citation Excerpt :

    Structured and standardized scales have been developed to improve patient interviews and self-reports, including the Brief Adherence Rating Scale (BARS) (Byerly et al., 2008), the Medication Adherence Rating Scale (MARS) (Fialko et al., 2008), the Brief Evaluation of Medication Influences and Beliefs (BEMIB) (Dolder et al., 2004), and the Drug Attitude Inventory (DAI) (Awad, 1993). As a presumably more objective measure electronic monitoring via a microchip-imbedded cap to capture each pill bottle opening appeared in the literature during the 1980s (Cramer et al., 1989; Spector et al., 1986) and has been used increasingly in addition to pill counts (Cramer and Rosenheck, 1999; Nakonezny et al., 2008). Despite advances in measurement methodologies, there has been scant research examining the concordance among measures of adherence to antipsychotics or appraisal of their validity versus a reference standard.

  • Evaluation of adherence patterns in schizophrenia using electronic monitoring (MEMS®): A six-month post-discharge prospective study

    2018, Schizophrenia Research
    Citation Excerpt :

    While factors associated with medication non-adherence are known, the identification of patients with poor adherence remains an important challenge in clinical practice (Misdrahi et al., 2016). Most prior studies investigating medication adherence, however, have relied on subjective or indirect methods such as self-reports, provider-reports, or chart reviews to assess adherence (Nakonezny et al., 2008; Osterberg and Blaschke, 2005; Velligan et al., 2006). Electronic medication event monitoring is regarded as the most reliable measure of adherence (Chesney, 2006; Velligan et al., 2009).

  • Twelve months of electronic monitoring (MEMS<sup>®</sup>) in the Swedish COAST-study: A comparison of methods for the measurement of adherence in schizophrenia

    2014, European Neuropsychopharmacology
    Citation Excerpt :

    The MEMS® has a medication bottle cap equipped with a microprocessor that records the occurrence and time of each bottle opening. The reliability and predictive validity for MEMS® has been shown to be high (Nakonezny et al., 2008). However, the MEMS® approach has its drawbacks as it requires regular monitorings and the technique cannot detect pill discarding (Farmer, 1999; Goff et al., 2010).

View all citing articles on Scopus
View full text