Reliability of a patient-reported outcome measure in schizophrenia: Results from back-to-back self-ratings

Psychometric evaluation of the patient-reported experience of cognitive impairment in schizophrenia (PRECIS) scale

BACKGROUND

Cognitive impairment associated with schizophrenia (CIAS) represents a distinct, persistent, and core group of schizophrenia symptoms. Cognitive symptoms have been shown to have an impact on quality of life. There are several published CIAS measures, but none based on direct patient self-report. It is important to capture the patient's perspective to supplement performancebased outcome measures of cognition to provide a complete picture of the patient's experience. This paper describes additional validation work on the Patient-Reported Experience of Cognitive Impairment in Schizophrenia (PRECIS) instrument.

METHODS

Data from two large, international, pharmaceutical clinical trials in medically and psychiatrically stable English-speaking patients with schizophrenia and 88 healthy controls were analyzed. An exploratory factor analysis (EFA) was conducted in one trial (n = 215), using the original 35-item PRECIS. The factor structure suggested by EFA was further evaluated using item response theory (IRT; Samejima's graded response model), and tested using confirmatory factor analysis (CFA). Both EFA and CFA results were tested in a second trial with similar inclusion/exclusion characteristics (n = 410). Additional statistical properties were evaluated in healthy controls.

RESULTS

EFA suggested that the best solution after item reduction suggested a factor structure of 6 factors based on 26 items (memory, communication, self-control, executive function, attention, sharpness of thought), supporting a total score, with an additional 2-item bother score (28 items in all). IRT analysis indicated the items were well-ordered within each domain. The CFA demonstrated excellent model fit, accounting for 69% of the variance. The statistical properties of the 28-item version of the PRECIS were confirmed in the second trial. Evidence for internal consistency and test-retest reliability was robust. Known-groups validity was supported by comparison of healthy controls with patients with schizophrenia. Correlations indicated moderate associations between PRECIS and functioning instruments like the Schizophrenia Cognition Rating Scale (SCoRS), but weak correlations with performance-based outcomes like MATRICS Consensus Cognitive Battery (MCCB).

DISCUSSION

Using two clinical trial samples, we identified a robust factor structure for the PRECIS and were able to replicate it in the second sample. Evaluation of the meaningful score difference (MSD) should be repeated in future studies, as these samples did not show enough change for it to be evaluated.

CONCLUSIONS

This analysis provides strong evidence for the reliability and validity of the PRECIS, a 28-item, patient-reported instrument to assess cognitive impairment associated with schizophrenia. The correlation with functioning and the weak correlation with performance on cognitive tasks suggests that patient reports of cognitive impairment measure a unique aspect of patient experience.

Awareness of illness moderates self-assessment of psychotic symptoms

OBJECTIVE

Self-reports or patient-reported outcome measures are seldom used in psychosis due to concerns about the ability of patients to accurately report their symptomatology, particularly in cases of low awareness of illness. The aim of this study was to assess the effect of insight on the accuracy of self-reported psychotic symptoms using a computerized adaptive testing tool (CAT-Psychosis).

METHODS

A secondary analysis of data drawn from the CAT-Psychosis development and validation study was performed. The Brief Psychiatric Rating Scale and the Scale of Unawareness of Mental Disorders were administered by clinicians. Patients completed the self-reported version of the CAT-Psychosis. Patients were median-split regarding their insight level to compare the correlation between the two psychosis severity measures. A subgroup sensitivity analysis was performed only on patients with schizophrenia spectrum disorders.

RESULTS

A total of 159 patients with a psychotic disorder who completed both CAT-Psychosis and Scale of Unawareness of Mental Disorders were included. For the whole sample, CAT-Psychosis scores showed convergent validity with Brief Psychiatric Rating Scale ratings (r = 0.517, 95% confidence interval = [0.392, 0.622], p < 0.001). Insight was found to moderate this correlation (β = -0.511, p = 0.005), yet agreement between both measures remained statistically significant for both high (r = 0.621, 95% confidence interval = [0.476, 0.733], p < 0.001) and low insight patients (r = 0.408, 95% confidence interval = [0.187, 0.589], p < 0.001), while psychosis severity was comparable between these groups (for Brief Psychiatric Rating Scale: U = 3057, z = -0.129, p = 0.897; disorganization: U = 2986.5, z = -0.274, p = 0.784 and for CAT-Psychosis: U = 2800.5, z = -1.022, p = 0.307). Subgroup of patients with schizophrenia spectrum disorders showed very similar results.

CONCLUSIONS

Insight moderates the correlation between self-reported and clinician-rated severity of psychosis, yet CAT-Psychosis remains valid in patients with both high and low awareness of illness.

Cautionary Observations Concerning the Introduction of Psychophysiological Biomarkers into Neuropsychiatric Practice

The combination of statistical learning technologies with large databases of psychophysiological data has appropriately generated enthusiastic interest in future clinical applicability. It is argued here that this enthusiasm should be tempered with the understanding that significant obstacles must be overcome before the systematic introduction of psychophysiological measures into neuropsychiatric practice becomes possible. The objective of this study is to identify challenges to this effort. The nonspecificity of psychophysiological measures complicates their use in diagnosis. Low test-retest reliability complicates use in longitudinal assessment, and quantitative psychophysiological measures can normalize in response to placebo intervention. Ten cautionary observations are introduced and, in some instances, possible directions for remediation are suggested.

Applying machine learning to smartphone based cognitive and sleep assessments in schizophrenia

Background

Methods

Results

Discussion

Aripiprazole lauroxil 2-month formulation with 1-day initiation in patients hospitalized for an acute exacerbation of schizophrenia: exploratory efficacy and patient-reported outcomes in the randomized controlled ALPINE study

BACKGROUND

A randomized, controlled, phase 3b study (ALPINE) evaluated efficacy and safety of a 2-month formulation of aripiprazole lauroxil (AL) using a 1-day initiation regimen in patients hospitalized for an acute exacerbation of schizophrenia. Paliperidone palmitate (PP) was used as an active control. Exploratory endpoint assessments included severity of illness, positive and negative symptoms, quality of life, caregiver burden, and satisfaction with medication.

METHODS

Adults were randomly assigned to AL 1064 mg q8wk or PP 156 mg q4wk as inpatients, discharged after 2 weeks, and followed through week 25. Exploratory efficacy measures included the 3 original PANSS subscales, Clinical Global Impression-Severity (CGI-S) subscale, and caregiver Burden Assessment Scale. Exploratory patient-reported outcomes (PROs) included the Quality of Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF) and the Medication Satisfaction Questionnaire. Within-group changes from baseline through week 25 were analyzed for AL and PP separately. PROs were summarized based on observed data.

RESULTS

Of 200 patients randomized (AL, n = 99; PP, n = 101), 99 completed the study (AL, n = 56; PP, n = 43). For AL, PANSS subscale and CGI-S scores improved from baseline through week 25 (mean [SE] change from baseline at week 25: Positive, -7.5 [0.70]; Negative, -3.9 [0.46]; General, -11.8 [0.83]; CGI-S, -1.3 [0.12]). Caregiver burden also improved (mean [SD] changes from baseline at week 9: -8.4 [10.15]; week 25: -8.9 [12.36]). Most AL patients were somewhat/very satisfied with treatment at each timepoint (70.8%-74.7%); mean Q-LES-Q-SF total scores were stable in the outpatient period. For PP, results were similar: PANSS Positive, -7.3 (0.67); Negative, -3.6 (0.69); General, -10.9 (1.22); CGI-S, -1.4 (0.16); caregiver burden, week 9: -8.8 (11.89) and week 25: -9.2 (14.55); satisfaction with treatment, 64.7%-69.3%; and stable Q-LES-Q-SF scores.

CONCLUSIONS

ALPINE patients initiating the 2-month AL formulation using the 1-day initiation regimen as inpatients and continuing outpatient care experienced schizophrenia symptom improvement, sustained patient satisfaction with medication, stable quality of life, and reduced caregiver burden. A similar benefit pattern was observed for PP. These results support the feasibility of starting either long-acting injectable in the hospital and transitioning to outpatient treatment.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03345979 [trial registration date: 15/11/2017].

Reliability of the Glasgow Antipsychotic Side-effects Scale for Clozapine Japanese version (GASS-C-J)

The purpose of this study was to develop the Glasgow Antipsychotic Side effects Scale for Clozapine Japanese version (GASS-C-J) and examine its reliability to assess clozapine-related side effects. We developed the GASS-C-J using forward and backward translation. Semantic equivalence of the GASS-C-J to the GASS-C was confirmed by the original author. We then administered the GASS-C-J twice to 109 patients on clozapine treatment at two psychiatric hospitals in Japan. We assessed the internal consistency and test-retest reliability of the GASS-C-J using Cronbach's alpha and weighted kappa coefficient, respectively. We also examined if discrepancies in each GASS-C-J item score between the first and second rating were correlated with items of the Brief Evaluation of Psychosis Symptom Domains (BE-PSD). The Cronbach's alpha coefficient of the GASS-C-J at the first and second rating was 0.78 (95% CI: 0.72 to 0.84) and 0.82 (95% CI: 0.76 to 0.88), respectively. The weighted kappa coefficient of individual and total GASS-C-J item scores ranged from 0.45 to 0.88. Some symptom domains were correlated with discrepancies in specific items of the GASS-C-J: psychotic symptoms and nausea/vomiting (rs = 0.27), thirst (rs = 0.31), and appetite/weight gain (rs = 0.27); disorganized thinking and urinary incontinence (rs = 0.26); depression/anxiety and myoclonus (rs = 0.25), hypersalivation (rs = -0.27), and blurred vision (rs = -0.22). These findings demonstrate that the GASS-C-J can be used in clinical and research settings as a reliable scale to assess clozapine-related side effects.

Measuring the Burden of Schizophrenia Using Clinician and Patient-Reported Measures: An Exploratory Analysis of Construct Validity

BACKGROUND

Various self-reported or clinician-reported (as a proxy) measures exist to quantify the burden of schizophrenia on patients. Evidence of the psychometric relationship between these measures to inform their practical use is limited.

OBJECTIVES

Our objective was to conduct an exploratory analysis of the construct validity of patient-reported (EQ-5D, SF-6D, WEMWBS, SQLS subscales of Psychosocial, Motivation, Symptoms) versus clinician-reported measures (PANSS, CGI-SCH, NSA-4, HoNOS-PbR) to inform future use of patient-reported measures for burden-of-illness assessment and/or economic evaluation.

METHODS

In an adult patient population with schizophrenia, construct validity was assessed in relation to convergent and known-group validity. Convergent validity was assessed using Spearman's rank absolute correlation strength (ACS: weak ≤ 0.3, moderate = 0.3 < 0.5, strong ≥ 0.5) and graphically using locally weighted scatterplot smoothing (LOWESS) techniques. Known-group validity was assessed using Cohen's d absolute effect size (AES: small ≤ 0.5, moderate = 0.5 < 0.8, large ≥ 0.8). Floor and ceiling effects were assessed as a proxy of sensitivity in this cross-sectional study. Statistical significance was assessed at the 5% threshold level (p < 0.05). Across head-to-head assessments, the frequency of producing the strongest ACS, largest AES, and statistically significant results determined the best overall construct validity.

RESULTS

Overall, 304 patients consented to the study. In relation to statistically significant results, the SF-6D most frequently exhibited the strongest ACS and largest AES against the clinician-reported measure scores (ACS range 0.084-0.436; AES range 0.043-0.746), and the SQLS Motivation subscale most frequently exhibited the weakest/smallest values (ACS range 0.009-0.157; AES range 0.002-0.397), although these results were mixed according to the clinician-reported measure used for comparative analysis (ACS range 0.009-0.529; AES range 0.002-0.934).

CONCLUSION

The SF-6D indicated the best (mostly moderate) construct validity but still missed the negative symptoms of the condition. Although further evidence is required to confirm or refute these exploratory results, compared with the EQ-5D, the SF-6D can be self-reported to better capture generic health-related quality-of-life aspects of schizophrenia for the purpose of economic evaluation. The lack of construct validity for SQLS Motivation and Symptoms subscales were hypothesized post-hoc to be representative of the complementary information elicited by the subscales not captured by the clinician-reported measures. Therefore, the SQLS can be self-reported to capture complementary (i.e., additional) information relative to clinician-reported measures.

Retinal correlates of psychiatric disorders

Diagnosis and monitoring of psychiatric disorders rely heavily on subjective self-reports of clinical symptoms, which are complicated by the varying consistency of accounts reported by patients with an impaired mental state. Hence, more objective and quantifiable measures have been sought to provide clinicians with more robust methods to evaluate symptomology and track progression of disease in response to treatments. Owing to the shared origins of the retina and the brain, it has been suggested that changes in the retina may correlate with structural and functional changes in the brain. Vast improvements in retinal imaging, namely optical coherence tomography (OCT) and electrodiagnostic technology, have made it possible to investigate the eye at a microscopic level, allowing for the investigation of potential biomarkers in vivo. This review provides a summary of retinal biomarkers associated with schizophrenia, bipolar disorder and major depression, demonstrating how retinal biomarkers may be used to complement existing methods and provide structural markers of pathophysiological mechanisms that underpin brain dysfunction in psychiatric disorders.

Well-being in patients with schizophrenia, mood and personality disorders attending psychiatric services in the community. A controlled study

BACKGROUND

Poor attention is paid by recent research to the prevalence of mental well-being in psychiatric patients and the comparison between groups with different diagnoses. Data suggest that the presence of mental illness does not necessarily mean the absence of well-being, particularly in stable outpatients.

METHODS

A consecutive series of 375 patients attending two community mental health centers was given the Mental Health Continuum Short Form (MHC-SF) and the Clinical Global Impression - Severity scale. Diagnoses were made after the MINI Neuropsychiatric Interview and a chart review of all relevant clinical information. The flourishing category and the three components of MHC-SF were used to rate well-being. A total of 274 controls were taken from the employees at a local firm.

RESULTS

The rates of flourishing mental health were: 33.1% schizophrenia, 36.6% bipolar disorder, 23.3% unipolar depression, 24.4% cluster B personality disorder, and 53.3% controls (p < 0.001). The comparison of the three MHC components across diagnostic groups found that unipolar depression and cluster B personality patients had significantly lower scores compared to bipolar and schizophrenia patients. Flourishing mental health was detected more often in males than females (34.9% vs. 24.1% - p < 0.05). For schizophrenia patients indices of well-being were better in those on depot medications.

CONCLUSIONS

Psychiatric outpatients with major mental illness have lower rates of well-being compared to controls, although about one-third is flourishing. Patients with unipolar depression and cluster B personality disorder may deserve special attention when planning intervention for fostering well-being.

A meta-analytic review of self-reported, clinician-rated, and performance-based motivation measures in schizophrenia: Are we measuring the same "stuff"?

An array of self-reported, clinician-rated, and performance-based measures has been used to assess motivation in schizophrenia; however, the convergent validity evidence for these motivation assessment methods is mixed. The current study is a series of meta-analyses that summarize the relationships between methods of motivation measurement in 45 studies of people with schizophrenia. The overall mean effect size between self-reported and clinician-rated motivation measures (r = 0.27, k = 33) was significant, positive, and approaching medium in magnitude, and the overall effect size between performance-based and clinician-rated motivation measures (r = 0.21, k = 11) was positive, significant, and small in magnitude. The overall mean effect size between self-reported and performance-based motivation measures was negligible and non-significant (r = -0.001, k = 2), but this meta-analysis was underpowered. Findings suggest modest convergent validity between clinician-rated and both self-reported and performance-based motivation measures, but additional work is needed to clarify the convergent validity between self-reported and performance-based measures. Further, there is likely more variability than similarity in the underlying construct that is being assessed across the three methods, particularly between the performance-based and other motivation measurement types. These motivation assessment methods should not be used interchangeably, and measures should be more precisely described as the specific motivational construct or domain they are capturing.

Ginkgo biloba induced mood dysregulation: a case report

Background

Impairment of cognitive function as well as negative symptom is the major factor causing the decline of a patient’s functioning in chronic stages of schizophrenia. However, until now, there were no definite treatment options that could effectively reduce the impairment.

Case presentation

We report a case of mood dysregulation associated with use of Ginkgo biloba in a patient with schizophrenia. After Ginkgo biloba was given, the patient experienced cluster symptoms of mood dysregulation including irritability, difficulty in controlling anger, agitation and restlessness. We estimated the possibility as “probable” according to Naranjo scale considering circumstantial evidence.

Conclusions

This case suggests that Ginkgo biloba may have caused mood dysregulation in this patient. Although it is generally accepted as safe, more attention should be given to the adverse effect when treating with Ginkgo biloba.