Glenn A. Phillips

The effects of psychological therapies under clinically representative conditions: A meta-analysis.

Recently, concern has arisen that meta-analyses overestimate the effects of psychological therapies and that those therapies may not work under clinically representative conditions. This meta-analysis of 90 studies found that therapies are effective over a range of clinical representativeness. The projected effects of an ideal study of clinically representative therapy are similar to effect sizes in past meta-analyses. Effects increase with larger dose and when outcome measures are specific to treatment. Some clinically representative studies used self-selected treatment clients who were more distressed than available controls, and these quasi-experiments underestimated therapy effects. This study illustrates the joint use of fixed and random effects models, use of pretest effect sizes to study selection bias in quasi-experiments, and use of regression analysis to project results to an ideal study in the spirit of response surface modeling.

GPT.EXE: A powerful tool for the visualization and analysis of general processing tree models

This paper introduces GPT.EXE, a computer program for designing and implementing general processing tree (GPT) models. First, designing and building GPT models using this program is discussed. The second major emphasis is a description of various statistical procedures that can be carried out with GPT.EXE. There is also a brief section on the on-line documentation of this program. Throughout the text, pictures of windows from the program are displayed to help explain the procedures being described by the text.

Intraclass Correlation for Measures from a Middle School Nutrition Intervention Study: Estimates, Correlates, and Applications

This article presents the first estimates of school-level intraclass correlation for dietary measures based on data from the Teens Eating for Energy and Nutrition at School study. This study involves 3,878 seventh graders from 16 middle schools from Minneapolis–St. Paul, Minnesota. The sample was 66.8% White, 11.2% Black, and 7.0% Asian; 48.8% of the sample was female. Typical fruit and vegetable intake was assessed with a modified version of the Behavior Risk Factor Surveillance System questionnaire. Twenty-four-hour dietary recalls were conducted by nutritionists using the Minnesota Nutrition Data System. Mixed-model regression methods were used to estimate variance components for school and residual error, both before and after adjustment for demographic factors. School-level intraclass correlations were large enough, if ignored, to substantially inflate the Type I error rate in an analysis of treatment effects. The authors show how to use the estimates to determine sample size requirements for future studies.

Comprehensive review of factors implicated in the heterogeneity of response in depression

Heterogeneity in overall response and outcomes to pharmacological treatment has been reported in several depression studies but with few sources that integrate these results. The goal of this study was to review the literature and attempt to identify nongenetic factors potentially predictive of overall response to depression treatments.

Reasons for discontinuation and continuation of antipsychotics in the treatment of schizophrenia from patient and clinician perspectives.

Abstract Objective: To identify reasons for discontinuation and continuation of antipsychotic medications in the treatment of schizophrenia from the patients’ and their clinicians’ perspectives. Research design and methods: Two measures were previously developed to assess the Reasons for Antipsychotic Discontinuation/Continuation (RAD), one from the patients perspective and another from the clinicians perspective. These measures were administered to acutely ill schizophrenia patients enrolled in a 12-week study of antipsychotic medications (N = 596) and to their clinicians. The RAD was assessed at baseline and at endpoint. Reasons were rated on a 5-point scale from ‘primary reason’ to ‘not a reason.’ The single most important reason was also identified. The ‘single most important reason’ and the ‘primary reasons’ for discontinuing the drug used prior to enrollment, and for discontinuing or continuing the study drug were identified. Levels of concordance between patients’ and clinicians’ reasons were assessed. Clinical trial registration: The data source for this study is a clinical trial registered at www.clinicaltrials.gov (NCT00337662). Main outcome measures: Reasons for Antipsychotic Discontinuation/Continuation (RAD). Results: Patients and clinicians identified several reasons for medication discontinuation and continuation (2.3 to 6.3 reasons, on average). The top ‘single most important’ reason for discontinuing the drug used prior to enrollment and for discontinuing the study drug was ‘positive symptoms not sufficiently improved or made worse,’ followed by ‘medication-related adverse events.’ The most frequent ‘single most important’ reason for medication continuation was ‘improved positive symptoms,’ followed by ‘patients perception of improvement,’ and ‘functional improvement.’ A high level of concordance was observed between patients’ and clinicians’ ratings. Conclusions: Medication efficacy appears to be the core driver of medication discontinuation and continuation, especially with regard to positive symptoms. There was a high level of concordance between patients’ and clinicians’ perspectives. Limitations include the study requirement that patients be at least moderately ill and experiencing acute psychotic exacerbation, a potential selection bias in the readiness to respond to measures, and small sample sizes for some analyses. Further research is needed to replicate findings in patients who are not acutely ill.

Antipsychotic adherence, switching, and health care service utilization among Medicaid recipients with schizophrenia

Objective: To evaluate health care resource utilization in patients with schizophrenia who continued newly prescribed antipsychotic medications, compared with those switching to different treatments. Methods: Adults with schizophrenia in the California Medicaid (MediCal) database who initiated treatment with index medications in 1998–2001, were classified as having: 1) abandoned antipsychotic medications; 2) switched to another medication; or 3) continued with the index antipsychotic, for up to 6 months after the index date. Results: Of 2300 patients meeting eligibility criteria, 1382 (60.1%) continued index medications, 480 (20.9%) switched, and 438 (19.0%) abandoned antipsychotic treatment. Utilization in several resource categories occurred significantly more frequently among patients whose regimens were switched (vs those continuing index medications). These included using psychiatric (24.2% vs 14.5%; P < 0.001) or nonpsychiatric (31.5% vs 24.3%; P < 0.05) emergency services; being admitted to a hospital (10.6% vs 7.4%; P < 0.05); making nonpsychiatric outpatient hospital visits (43.3% vs 36.4%; P < 0.05) or nonpsychiatric physician visits (62.7% vs 56.4%; P < 0.05); and using other outpatient psychiatric (53.3% vs 40.7%; P < 0.001) or nonpsychiatric (82.7% vs 74.6%; P < 0.001) services. Conclusions: Switching antipsychotic medications is associated with significantly increased health care resource utilization (vs continuing treatment).

Increased olanzapine discontinuation and health care resource utilization following a Medicaid policy change.

OBJECTIVE To assess the short-term impact of Florida Medicaids policy change on olanzapine discontinuation and health care resource utilization among olanzapine-treated patients with schizophrenia or bipolar diagnoses. The announced policy change, effective on July 11, 2005, but rescinded on September 9, 2005, reclassified olanzapine as nonpreferred and gave physicians 60 days to change antipsychotics for current users. METHOD Prescription patterns, health care resource utilization, and Medicaid payments were compared between patients using olanzapine on July 11, 2005, and matched prior-year controls. For reference, parallel analyses were conducted in New Jersey Medicaid, where access to olanzapine remained constant. The effect of Floridas policy change was also estimated among policy-sensitive olanzapine users by treating year (2004 vs 2005) as an instrumental variable. RESULTS Matched Florida cohorts (N = 4,255) showed increases from 2004 to 2005 in 6-month rates of switching from olanzapine (+326%), hospitalization (+19.8%), and emergency room visits (+19.7%) (all P values < .001). Concurrently in the matched New Jersey cohorts (N = 2,680), there were no significant changes in these outcomes from 2004 to 2005. Among matched Florida policy-sensitive olanzapine users, an additional 9.3% experienced hospitalization in 2005 versus 2004 (P < .001), and increased payments for medical services and other antipsychotics largely offset decreased payments for olanzapine. CONCLUSIONS The announced reclassification of olanzapine to nonpreferred status substantially disrupted the continuity of olanzapine therapy for many Florida Medicaid recipients diagnosed with schizophrenia or bipolar disorder and was associated with increased hospitalization and emergency room visits. During the 6 months following the policy change, increased payments for medical services largely offset reduced payments for olanzapine.

Effects of a Psychotherapeutic Drug Prior Authorization (PA) Requirement on Patients and Providers: A Providers’ Perspective

This study describes the effects of a Texas Medicaid PA requirement for psychotherapeutic medications from the perspective of mental health care providers. Three focus groups were conducted and a content analysis was performed on the generated transcripts. Providers identified five categories of issues that are relevant to the PA process: (1) system/administrative factors; (2) costs/ outcomes; (3) prescribing issues; (4) evaluation criteria; and (5) patient–provider relationship and patient visit. Administrative burden and unintended patient outcomes were the most frequently reported issues related to PA. However, all five issues represent important factors that providers deal with when caring for patients with mental illness.

Development of a clinician questionnaire and patient interview to assess reasons for antipsychotic discontinuation

Time to treatment discontinuation and rates of discontinuation are commonly used when evaluating effectiveness of antipsychotic medication. However, less is known about reasons for discontinuation. The purpose of this study was to develop two measures of reasons for discontinuation or continuation of antipsychotics for the treatment of schizophrenia. Based on literature review, a patient interview pilot study, and expert panel input, two measures were drafted: the clinician-reported Reasons for Antipsychotic Discontinuation/Continuation Questionnaire (RAD-Q) and the patient-reported Reasons for Antipsychotic Discontinuation/Continuation Interview (RAD-I). Patients and clinicians completed the draft measures and structured cognitive debriefing interviews. For the draft instruments, reasons for discontinuation/continuation were divided into 3 categories: therapeutic benefits (positive symptoms, negative symptoms, mood, cognition, functional status), adverse events, and reasons other than direct effects of the medication (e.g., cost, inadequate social support). In cognitive debriefings, 10 clinicians and 15 patients indicated that the RAD-Q and RAD-I were clear, easy to complete, and comprehensive. Clinicians and patients suggested minor revisions, and the instruments were revised accordingly. The RAD-Q and RAD-I appear to be useful instruments for assessing reasons for antipsychotic discontinuation and continuation. The next step is a psychometric evaluation of the measures in a larger sample.

Reasons for continuing or discontinuing olanzapine in the treatment of schizophrenia from the perspectives of patients and clinicians

Background The aim of this study was to assess the reasons for discontinuing or continuing olanzapine in patients with schizophrenia, from the perspectives of the patients and their clinicians. Methods The Reasons for Antipsychotic Discontinuation/Continuation (RAD) is a pair of questionnaires assessing these reasons from the perspectives of patients and their clinicians. Outpatients with schizophrenia (n = 199) who were not acutely ill participated in a 22-week open-label study of olanzapine from November 2006 to September 2008. Reasons for continuing or discontinuing olanzapine (on a five-point scale), along with the single most important reason and the top primary reasons, were identified. Concordance between reasons given by patients and clinicians was assessed. Results The top primary reasons for continuing olanzapine were patients’ perceptions of improvement, improvement of positive symptoms, and improved functioning. The study discontinuation rate was low (30.2%), and only a subset of patients who discontinued reported reasons for medication discontinuation. The top primary reasons for discontinuing olanzapine were insufficient improvement or worsening of positive symptoms, adverse events, and insufficient improvement or worsening of negative symptoms. Ratings given by patients and clinicians were highly concordant. Conclusion The main reason for continuing or discontinuing olanzapine appears to be medication efficacy, especially for positive symptoms. Reasons for medication discontinuation differ somewhat from reasons for continuation, with a high level of concordance between patient and clinician responses.