Accounting for group differences in study retention in a randomized trial of specialized treatment for first episode psychosis (original) (raw)
Related papers
The impact of missing data on the results of a schizophrenia study
Pharmaceutical statistics
Missing data pose a serious challenge to the integrity of randomized clinical trials, especially of treatments for prolonged illnesses such as schizophrenia, in which long-term impact assessment is of great importance, but the follow-up rates are often no more than 50%. Sensitivity analysis using Bayesian modeling for missing data offers a systematic approach to assessing the sensitivity of the inferences made on the basis of observed data. This paper uses data from an 18-month study of veterans with schizophrenia to demonstrate this approach. Data were obtained from a randomized clinical trial involving 369 patients diagnosed with schizophrenia that compared long-acting injectable risperidone with a psychiatrist's choice of oral treatment. Bayesian analysis utilizing a pattern-mixture modeling approach was used to validate the reported results by detecting bias due to non-random patterns of missing data. The analysis was applied to several outcomes including standard measures o...
RAND Working …, 2006
Missing data is a pervasive problem in longitudinal treatment research studies. Missing data due to study non-completion complicate the task of drawing conclusions about the effect of a treatment or policy on a measure of interest (e.g., a process measure or outcome). Biased estimates of change over time in a measure could result if attrition is related to the constructs that are being measured. Identifying potential biases in estimates is critical for research involving longitudinal assessments. The pattern-mixture model (PMM) provides a way to understand and account for attrition when analyzing data and communicating results to research stakeholders. This paper demonstrates the use of PMMs in a study of the quality of care in therapeutic communities (TCs) using the Dimensions of Change Instrument (DCI) to measure longitudinal client-level change and TC treatment process. The effect of choice of missing data pattern and its effects on conclusions drawn from analyses is highlighted along with the role of clinical expertise in formulating PMMs.
Schizophrenia Research, 2006
This paper introduces a health state modeling approach using clustering and Markov analysis to compare short-and long-term outcomes among health care populations. We provide a comparison to more conventional mixed effects regression methods and show that discrete state modeling offers a richer portrait of patient outcomes than the standard univariate techniques. We demonstrate our approach using primary data from a three year observational study of patients treated for schizophrenia at a VA Medical Center (VA) and in a Community Mental Health Center (CMHC) in the same urban community. Randomly selected samples of outpatients treated for schizophrenia or schizoaffective disorder were interviewed every six months using standardized psychiatric assessments such as the Positive and Negative Syndrome Scale (PANSS). Items from the PANSS were used to define 7 discrete health states representing different levels of severity and diverse mixtures of psychiatric symptoms. Conventional analysis showed that VA patients exhibited increasingly severe symptoms, while CMHC patients remained more stable over the study period. Health state analysis reinforced these results but also identified which subpopulations of VA patients were deteriorating. In particular they showed that there was little change over time among VA patients in the best and worst health states. Instead the deterioration was caused by VA patients with: a) mild symptoms and hallucinations and b) serious positive and negative symptoms, being more likely to enter a state with severe positive and negative symptoms accompanied by moderate general distress.
Psychiatric Rehabilitation Journal, 2013
Objective: Most research on the Illness Management and Recovery (IMR) program for people with severe mental illnesses has focused on individuals with stable symptoms living in the community, with less attention to persons being treated in an inpatient setting. We evaluated the feasibility and effects of an IMR program adapted for individuals with schizophrenia who were awaiting discharge into the community. Method: A randomized controlled trial was conducted at 2 hospitals in Taiwan to compare the adapted IMR program with treatment as usual (TAU). Ninety-seven individuals with schizophrenia were randomized to the adapted IMR program or TAU. Four outcome indicators including illnessmanagement knowledge, attitudes toward medication, insight, and symptoms were assessed at baseline, posttreatment, and at a 1-month follow-up following discharge from the hospital. Results: Participants in the adapted IMR group showed significantly greater improvements at posttreatment and 1-month follow-up in illness-management knowledge, attitudes toward medication, insight, and negative symptoms on the Brief Psychiatric Rating Scale (BPRS) than individuals in the TAU group. There were no significant differences between the 2 groups on other subscales of the BPRS. Conclusions and Implications for Practice: This is the first controlled evaluation of a version of the IMR program in an East Asian culture, and the first to evaluate it in an acute care inpatient setting. Our findings support the feasibility and potential benefits of implementing an adapted IMR program, focused on the prevention of relapses and rehospitalizations, during the discharge period of an inpatient treatment stay to prepare individuals to reenter the community.
Schizophrenia Research, 2007
Research in schizophrenia and related severe mental illness (SMI) suggests that psychiatric rehabilitation facilitates recovery of psychosocial functioning although there is considerable heterogeneity in outcomes. The present study used growth mixture modeling (GMM), a longitudinal latent variable modeling strategy, to identify classes of psychosocial functioning recovery trajectories. Archival clinical assessment data representing the first 18 months of an inpatient psychiatric rehabilitation program were analyzed from a sample of participants with schizophrenia spectrum disorders (N = 162). Based on a GMM analysis of monthly Nurse Observation Scale for Inpatient Evaluation (NOSIE) scores two classes were identified that differed in overall level of psychosocial functioning, rate and nonlinear shape of change. The identified lower functioning group was characterized by poorer neurocognitive functioning at admission, a history of negative symptoms, more previous inpatient psychiatric days, and a longer length of stay in the rehabilitation program. However, this group showed significantly greater positive change in the NOSIE domains directly targeted by behavioral treatment: daily schedule competence, neatness, and irritability. Methodological and theoretical implications of these modeling strategies are discussed in the context of understanding the rehabilitation process.
BMC Psychiatry, 2013
Background: The aim of this study is to compare the 12-year follow-up effects on in-and outpatient services of 2 years of integrated treatment for recent-onset schizophrenia versus treatment as usual in a randomized controlled trial. Methods: 50 patients aged 18-35 years were randomized to Integrated Treatment (IT) (N = 30) or Treatment-as-Usual (TAU) (N = 20) for two years. TAU comprised optimal pharmacotherapy and outreach assertive treatment, while IT also included cognitive-behavioural family treatment, skills training, strategies for residual psychotic and non-psychotic problems and home-based crisis management. Results: There were no differences in number of days in hospital, time to readmission, number of admittances to psychiatric wards, number of involuntarily psychiatric admissions or number of outpatient contacts over a period of 12 years following the initial 2-year treatment trial. Fewer patients in the IT group were, however, involuntary admitted to hospital in the period. Conclusions: The intensive two-year psychosocial intervention seemed to have little long-term effects on use of in-and outpatient services.
2021
Service providers need effective strategies to implement evidence-based practices (EBPs) with high fidelity. This study aimed to evaluate an intensive implementation support strategy to increase fidelity to EBP standards in treatment of patients with psychosis. The study used a cluster randomized design with pairwise assignment of practices within each of 39 Norwegian mental health clinics. Each site chose two of four practices for implementation: physical health care, antipsychotic medication management, family psychoeducation, illness management and recovery. One practice was assigned to the experimental condition (toolkits, clinical training, implementation facilitation, data-based feedback) and the other to the control condition (manual only). The outcome measure was fidelity to the EBP, measured at baseline and after 6, 12, and 18 months, analyzed using linear mixed models and effect sizes. The increase in fidelity scores (within a range 1–5) from baseline to 18 months was sign...
Schizophrenia Bulletin, 2003
Schizophrenia is a symptomatically heterogeneous disorder characterized by the presence of positive and negative symptoms, and variable impairment hi community functioning. Given the diversity of symptom presentations and functioning associated with schizophrenia, one of the key challenges facing the Clinical Antipsychotic Trials of Intervention Effectiveness (CATTE) schizophrenia trial was the selection of efficient assessment measures appropriate to a communitybased effectiveness trial. This article describes the rationale for the measurement approach adopted for the trial, provides a brief overview of the selected measures, and describes the process of training assessment raters for a large and geographically dispersed study group.
Social Psychiatry and Psychiatric Epidemiology, 2007
Objective Previous research has suggested that psychosis is better described as a continuum rather than a dichotomous entity. This study aimed to describe the distribution of positive psychosis-like symptoms in two large community samples using an item response mixture model. Method An item response mixture model was used to explain the pattern of psychosis-like symptom endorsement. This model incorporated two elements. First, a continuous non-normal latent variable to explain the observed pattern of data. Second, a categorical latent variable to explain the variation in the continuous non-normal latent variable. Results For both samples, representing broadly and narrowly defined psychosis, the best fitting model was a four-class solution. In both cases, the classes differed quantitatively rather than qualitatively. Conclusions The analysis showed that psychosis-like symptoms at the population level could be best explained by four classes that appeared to represent an underlying continuum.