The Patient Assessment Questionnaire: Initial validation of a measure of treatment effectiveness for patients with schizophrenia and schizoaffective disorder
Introduction
Despite early enthusiasm about the benefits of second-generation antipsychotics (SGAs) medications over older first-generation antipsychotics (FGAs), recent multi-site comparative trials of antipsychotic therapy effectiveness have failed to demonstrate meaningful differences in effectiveness between these treatments (Lieberman, 2006; Lieberman et al., 2005). According to the findings of two well-known and publicly-funded clinical studies (CATIE and CUTLASS), the two generations of antipsychotic drugs appear to be similar with regard to efficacy for psychosis, tolerability, and treatment compliance in schizophrenic patients (Jones et al., 2006, Carpenter and Buchanan, 2008; Lieberman et al., 2005). On the other hand, a multitude of recent studies, including the CATIE study, have consistently shown that FGAs and SGAs have distinct adverse side-effects profiles. It appears that while FGAs are associated more frequently with extrapyramidal side-effects, patients taking SGAs are at a higher risk of significant weight gain and metabolic disturbances (Kelly et al., 2008, Carpenter and Buchanan, 2008, Opjordsmoen et al., 2009). The implications of these distinct side-effect profiles for continuation of treatment and patient adherence highlights the importance of assessing not only the efficacy but also the effectiveness of the medication prescribed to schizophrenic patients in usual treatment settings. While efficacy assesses how well a drug treatment is working to alleviate symptoms in the context of a clinical trial, effectiveness studies evaluate the impact of treatments on health outcomes under conditions that approximate routine care (Gabbard et al., 1997). Assessments of effectiveness typically involve a simultaneous evaluation of the trade-offs between efficacy, safety, and tolerability in the context of routine care (Collaborative Working Group on Clinical Trial Evaluations, 1998). To be able to accurately evaluate the risks and benefits of available treatment options and to choose the optimal medication regimen for patients with schizophrenia, clinicians need to know about differences in effectiveness of antipsychotic medications. To this end, it is critical to have appropriate psychiatric measures to assess the effectiveness of psychotropic drugs in treatment of schizophrenia.
Standard instruments used in the assessments of clinical outcome in patients with schizophrenia, such as the Positive and Negative Syndrome Scale (PANSS) (Kay et al., 1987), and Scale for the Assessment of Positive Symptoms (SAPS) and Scale for the Assessment of Negative Symptoms (SANS) (Andreasen and Olsen, 1982), provide valuable information regarding symptoms and clinical outcome. However, these assessments are rated by clinicians and reflect their perspectives. Thus, they may not accurately reflect benefits and/or disadvantages of treatments as perceived by the patients. Such a subjective assessment is critical as patients' experience of their medication as intolerable and/or ineffective remains a primary cause of poor medication adherence and/or discontinuation (Lieberman et al., 2005).
Given the centrality of treatment adherence to clinical outcome, there has been increased interest in instruments assessing patients' own perspective of treatment in recent years. These measures show that it is possible to reliably and validly assess schizophrenic patients' subjective experience of clinical phenomena (Hellewell, 2002, Vothknecht et al., 2011) and that such measures are associated with both adherence and clinical outcome (Naber et al., 2001). Moreover, measures of subjective wellbeing have been able to differentiate medication classes (Voruganti et al., 2000, Hellewell, 2002). Many such measures, however, focus on specific domains of treatment and are not designed to simultaneously assess different aspects of treatment effectiveness in schizophrenia spectrum disorders from the patient perspective. For example, the Schizophrenia Outcomes Module (SCHIZOM) (Cuffel et al., 1997) mainly captures the symptoms of the illness and does not target issues of tolerability and safety. The Drug Attitudes Inventory (DAI) (Hogan et al., 1983) provides a measure of the overall valence (positive or negative) of subjects' feelings about their medications but does not address symptom reduction. Likewise, the Subjects' Response to Antipsychotics Questionnaire (SRA) covers a wide range of side effects associated with anti-psychotic treatment but does not assess psychopathology (Wolters et al., 2006). Other self-report measures of health outcomes target the domains of health-related quality of life (Derogatis and Melisaratos, 1983, Cuffel et al., 1997, Collaborative Working Group on Clinical Trial Evaluations, 1998, Collins et al., 1999, Dassori et al., 2003, Chinman et al., 2004), functioning (Endicott et al., 1993, Lehman et al., 2003), symptom-associated distress (Derogatis and Melisaratos, 1983), and treatment satisfaction (Collins et al., 1999, Gray et al., 2005, Rofail et al., 2005).
Several self-report measures explicitly address effectiveness and cover a broad array of treatment-relevant domains. The Subjective Wellbeing under Neuroleptic Treatment (SWN) (Naber et al., 2001, Vothknecht et al., 2011) is a 20-item self-report questionnaire with five subscales and a total scale. The subscales measure mental, social, emotional, and physical functioning and self-control. The Personal Evaluation of Transitions in Treatment (PETiT) is a 30-item scale that yields a single total score encompassing the following domains: psychological wellbeing, mood, energy level and activities, biological functions, self-esteem, coping abilities, cognition, communication, stigma, social functioning, aptitude towards productivity, and attitudes towards medication (Voruganti and Awad, 2002). Nonetheless, these instruments primarily address the “distal effectiveness” of antipsychotic treatment as it manifests in patients' general functioning in the world (Voruganti and Awad, 2002). Thus they do not target immediate indicators of effectiveness, such as symptom severity, side effects and general tolerability or safety—issues of critical concern in clinical trials.
In sum, although a number of instruments address treatment outcome from the patient's perspective, there remains significant need for a brief, self-report instrument that specifically targets effectiveness, incorporating measures of efficacy (i.e., symptom reduction), side effects and other domains related to tolerability and safety. As a compliment to clinician-rated assessments, such an instrument may enhance our ability to differentiate real world treatment impacts between antipsychotic agents and help illuminate patients' needs in the development of future antipsychotic medications.
In this paper we describe the development of an instrument specifically designed to provide a broad measure of subjective experience of medication treatment effectiveness in patients with schizophrenia spectrum disorders. Although ultimately effectiveness reflects change in patient functioning over time in response to treatment, this research serves as a necessary first step in the instrument development process. Here we demonstrate the psychometric validity of our instrument as a broad measure of psychiatric symptoms, medication side effects and general wellbeing. Specifically, we provide data on the feasibility, internal consistency and construct validity of our measure. Construct validity was derived both from factor analysis and from regression analyses with self-report measures of related constructs.
Section snippets
Subject recruitment
A total of 300 subjects diagnosed with either schizophrenia or schizoaffective disorder by DSM-IV-TR criteria participated in this study and completed the assessment. Participants were recruited through consecutive referrals from the psychiatric outpatient services at two hospitals located in New York City. Referrals were obtained by contacting hospital clinicians to inquire if any of their patients were interested in participating in the study. The study was also introduced to patients via
Subjects
A total of 302 subjects consented to the study and started the ACASI interview. However, two subjects discontinued the interview before completing it. The 300 subjects who completed the ACASI interview included 173 males and 127 females, all of whom carried a clinical diagnosis of either schizophrenia or schizoaffective disorder (37% schizoaffective disorder). Participants ranged in age from 19 to 72 (mean 46.74±11.1). The majority of subjects (67.3%) had never been married. Educational level
Discussion
Determining the effectiveness of medication treatment is a necessary component in both the successful management of schizophrenia-spectrum patients, as well as of the development of new and improved anti-psychotic medications. Investigation of the patients' subjective perspective regarding the effectiveness of their antipsychotic medication has up to now been hampered by the paucity of reliable and valid self-report measures that cover a broad range of clinically relevant domains. The ultimate
Acknowledgments
The authors would like to thank Susan Palmgren, Ph.D., from St. Luke's-Roosevelt Hospital Center for her support with subject recruitment. The authors would also like to acknowledge Jenny Williams, Alexis Newmark, Eda Inan, and Jamie Johnson for their hard work and dedication to subject recruitment and data collection.
References (53)
- et al.
Negative versus positive schizophrenia: definition and validation
Archives of General Psychiatry
(1982) - et al.
Development and validation of a patient-based health-related quality of life questionnaire in schizophrenia: the S-QoL
Schizophrenia Research
(2003) - et al.
Demographic characteristics and employment among people with severe mental illness in a multisite study
Community Mental Health Journal
(2006) - et al.
The AUDIT alcohol consumption questions (AUDIT-C)
Archives of Internal Medicine
(1998) - et al.
Lessons to take home from CATIE
Psychiatric Services
(2008) - et al.
Computer-assisted self-assessment in persons with severe mental illness
Journal of Clinical Psychiatry
(2004) Measuring outcomes in schizophrenia: differences among the atypical antipsychotics
Journal of Clinical Psychiatry
(1998)- et al.
Fever and acute brief psychosis in urban and rural settings in north India
British Journal of Psychiatry
(1999) - et al.
An instrument for measurement of outcomes of care for schizophrenia. Issues in development and implementation
Evaluation and Health Professions
(1997) - et al.
The approaches to schizophrenia communication (ASC) tool: including the patient perspective in treatment
DIS Manage Health Outcomes
(2003)
The brief symptom inventory: an introductory report
Psychological Medicine
Associations between adherence to guidelines for antipsychotic dose and health status, side effects, and patient care experiences
Medical Care
Quality of life enjoyment and satisfaction questionnaire: a new measure
Psychopharmacology Bulletin
Multitrait multimethod matrix and construct validity
The economic impact of psychotherapy: a review
American Journal of Psychiatry
A survey of patient satisfaction with and subjective experiences of treatment with antipsychotic medication
Journal of Advanced Nursing
Patients' subjective experiences of antipsychotics: clinical relevance
CNS Drugs
A self-report scale predictive of drug adherence in schizophrenics: reliability and discriminative validity
Psychological Medicine
Randomized controlled trial of the effect of quality of life of second- vs first-generation antipsychotic drugs in schizophrenia
Archives of General Psychiatry
Statistical analysis: an interdisciplinary introduction to univariate and multivariate methods
The positive and negative syndrome scale (PANSS) for schizophrenia
Schizophrenia Bulletin
Metabolic risk with second-generation antipsychotic treatment: a double-blind randomized 8-week trial of risperidone and olanzapine
Annals of Clinical Psychiatry
Ethnic differences in the presentation of bipolar affective disorder
European Psychiatry
Effectiveness, tolerability, and safety of ziprasidone in patients with schizophrenia or schizoaffective disorder: results of a multi-centre observational trial
European Psychiatry
The schizophrenia care and assessment program health questionnaire (SCAP-HQ): an instrument to assess outcomes of schizophrenia care
Schizophrenia Bulletin
Comparative effectiveness of antipsychotic drugs: a commentary on cost utility of the latest antipsychotic drugs in schizophrenia study (CUtLASS 1) and clinical antipsychotic trials of intervention effectiveness (CATIE)
Archives of General Psychiatry
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