Reliability of the Calgary depression scale for schizophrenia: A meta-analysis

BACKGROUND

A challenge for clinicians working with individuals diagnosed with schizophrenia is distinguishing depressive symptoms from negative symptoms of schizophrenia. The Calgary Depression Scale for Schizophrenia (CDSS) was developed for this purpose. No review has previously explored its reliability across multiple studies using advanced statistical means.

OBJECTIVES

This meta-analysis aimed to quantify the CDSS' internal consistency, inter-rater reliability (IRR) and test-retest reliability.

METHOD

A systematic literature search was conducted to find articles reporting on the CDSS' reliability. Articles were screened against the inclusion and exclusion criteria, with data extracted from 40 studies. Overall meta-analytic effects were calculated, and for internal consistency and IRR coefficients subsequent analyses explored between-study variation. The small test-retest reliability dataset limited analysis.

FINDINGS

The internal consistency meta-analytic effect was 0.83 (95% CI:0.82-0.84). Higgins I² indicated an acceptable level of variation between studies' alpha estimates. This suggests all items in the CDSS are measuring the same construct (i.e. symptoms of depression). The IRR meta-analytic effect was 0.88 (95% CI:0.86-0.91), with Higgins I² indicating high levels of heterogeneity. This was not deemed problematic variance as it is within levels expected for psychometric measures and, therefore, considered acceptable for this literature. This reflects high level of agreement between different raters when using the CDSS on the same client.

CONCLUSIONS

This review suggests the CDSS has good internal consistency and excellent IRR. Further research will help understand its test-retest reliability.

Stability of schizophrenia diagnosis in a 10-year longitudinal study on first episode of non-affective psychosis: Conclusions from the PAFIP cohort

OBJECTIVE

To evaluate the 10-year stability of schizophrenia diagnosis in a cohort of first-episode psychosis (FEP) patients and the factors associated with it.

METHODS

Changes in diagnosis of 209 FEP patients were described during 10 years of follow-up. Related factors with maintenance or change of schizophrenia diagnosis were evaluated in prospective and retrospective approaches through binary logistic regressions, ROC and survival curves.

RESULTS

Out of the 209 patients, 126 were diagnosed of schizophrenia 6 months after their inclusion in the clinical program. Prospective analyses showed that eight of those 126 schizophrenia patients had changed to a different diagnosis after 10 years, and predictors of change were better childhood premorbid adjustment, less severity of clinical global impression at baseline, and diagnosis of comorbid personality disorder during follow-up. Retrospectively, out of the 154 patients with schizophrenia in the 10-year assessment, 36 had a different diagnosis at baseline, and those factors related to a different prior diagnosis than schizophrenia were better socioeconomic status and shorter duration of untreated psychosis (DUP). A survival analysis on the timing of schizophrenia diagnosis showed that male gender and longer DUP were predictors of earlier definite diagnosis.

CONCLUSIONS

Diagnostic stability of schizophrenia in our FEP sample is high, especially prospective stability, and the group of patients with diagnostic change corresponded to a milder psychopathological profile before and at the onset of disease. Moreover, we observed a cautious attitude in the diagnosis of schizophrenia in patients with shorter DUP who had schizophrenia diagnosis after 10 years.

Inclusion of Gaming Disorder in ICD has more advantages than disadvantages

This paper is a response to a recent debate paper in which Aarseth et al. argue that the inclusion of a formal diagnosis and categories for problematic video gaming or Gaming Disorder (GD) in the World Health Organization's 11th Revision of the International Classification of Diseases (ICD-11) is premature and therefore the proposal should be removed. The present authors systematically address all the six main arguments presented by Aarseth et al. and argue that, even though some of the concerns presented in the debate paper are legitimate, the inclusion of GD in ICD-11 has more advantages than disadvantages. Furthermore, the present authors also argue that the two GD subtypes ("GD, predominantly online" and "GD, predominantly offline") are unnecessary and rather problematic; the main category for GD would be perfectly sufficient.

Changing trends in hospitalization rates associated with psychosis: Spain, 1980-2009

PURPOSE

To analyze the prevalence of hospitalization attributable to psychosis in Spain over the last three decades.

METHODS

Longitudinal analysis (1980-2009) of age-adjusted hospital discharges rates associated with psychosis (ICD9 290-8) in all Spanish hospitals.

DATA SOURCE

Spanish Hospital Morbidity Survey.

RESULTS

The hospitalization rate associated with psychotic episodes had been gradually increasing since 1980 until 2004; an abrupt turnaround observed in 2004 marks the beginning of a steady decline in the rate. The turning point described is not observed for each of the psychotic diagnoses separately analyzed. However, it is clearly seen when data are grouped in diagnosis-related groups (organic-psychosis, functional psychosis and substance-induced psychosis) since the time course of the diseases within the major diagnostic groups are interrelated as evidenced by shared turning points which collectively display a common time course pattern. Main hospital indicators and antipsychotic drug prescriptions were analyzed for any possible turning point in mid-2000s. Psychiatric hospital beds and length of stays remained stable by 2004; the hospitalizations associated with non-psychotic psychiatric pathologies show no turning point in 2004. However, an abrupt change on antipsychotic drug prescriptions is precisely observed in 2004.

CONCLUSIONS

After decades of linear growth, hospitalizations for psychotic patients begin to decline in 2004, coinciding with the start of last generation atypical antipsychotic drug consumption in Spain. Some of the psychotic diagnostic rates evolve in an interrelated manner which calls into question the diagnosis and nosological boundaries between some of these pathologies.

The nosology of schizophrenia: toward DSM-5 and ICD-11

Although dementia praecox or schizophrenia has been considered a unique disease entity for more than a century, definitions and boundaries have changed and its precise cause and pathophysiology remain elusive. Despite uncertain validity, the construct of schizophrenia conveys useful clinical and etiopathophysiologic information. Revisions of the Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Diseases seek to incorporate new information about schizophrenia and include elimination of subtypes, addition of psychopathological dimensions, elimination of special treatment of Schneiderian "first-rank" symptoms, better delineation of schizoaffective disorder, and addition of a new category of "attenuated psychosis syndrome".

Evaluation of the factor structure of symptoms in patients with schizophrenia

Considering the widespread use of the Positive and Negative Syndrome Scale (PANSS) and its factors around the world in clinical trials, it is clearly necessary to perform a transcultural validation of the factor structure of the PANSS. The purpose of the present study was to examine the PANSS factor structure in a Korean sample of subjects with schizophrenia. A total of 150 outpatients were assessed using the PANSS and other clinical rating scales. Principal component analyses revealed five factors, i.e., negative, cognitive/disorganization, positive, excitement, and depression/anxiety dimensions, which accounted for 64.1% of the total variance. All five factors showed good internal consistency, suggesting that the reliability of the factors extracted was adequate. Significant correlations were found between the five components of the PANSS and the corresponding clinical rating scales. The results of the present study indicate that the five-factor model best fit the data from our patients and that it was validated transculturally. The factor structures should be further validated using various neurobiological methods to ultimately help in clarifying the heterogeneity and pathogenesis of symptomatology in schizophrenia.

Trends on schizophrenia admissions during the deinstitutionalisation process in Spain (1980-2004)

BACKGROUND

The deinstitutionalisation reform in Spain started after 1980 with the aim of reducing the need for hospitalisation, length of stay and the number of psychiatric hospital beds, as well as fostering psychiatric patient's involvement in the community. The aim of this study was to review how this reform process has affected the management of schizophrenic patients from 1980 to 2004.

METHODS

Longitudinal (1980-2004) study describing variables related to hospital morbidity in schizophrenia patients.

RESULTS

Hospital admission rate has gradually increased from 1980 to 2004 from 3.71 admissions per 10,000 inhabitants to 5.89, respectively. Considering the type of admission, emergency or elective, whilst the latter has slightly decreased from 2.24 in 1980 to 1.72 in 2004, the first has almost tripled from 1.47 to 4.17. The point-prevalence of schizophrenic patients receiving inpatient treatment each year has decreased 78% in this period. Length of stay, in days per admission episode, has also decreased from 148 days in 1980 to 35 days in 2004.

CONCLUSION

One of the main impacts of the psychiatric health care reform in Spain has been the considerable reduction in hospital capacity devoted to schizophrenic patients, based on the significant decrease in point-prevalence. Thus, it seems relevant to design new studies to quantify the resource reallocation to other areas of care, such as pharmacological treatment and community services.

Testing the hypothesis that formal thought disorders are severe mood disorders

BACKGROUND

It was recently hypothesized by Lake (Schizophrenia Bulletin 2008; 34: 109-117) that Formal Thought Disorder (FTD) can be accounted for by a single disorder that is currently diagnosed as bipolar disorder.

OBJECTIVES

This study aimed to analyze the underlying dimensions of FTD and to examine to what extent FTD factors can be accounted for by clinical distractibility, attentional impairment, severity of mania, and familial liability of bipolar disorder and schizophrenia.

METHODS

Six hundred and sixty inpatients were assessed using a semistructured interview, and FTDs were assessed with the Thought, Language, and Communication scale. "Inattentiveness during Mental Status Testing" item of the Scale for the Assessment of Negative Symptoms scale and a composite mania score were used. The Family History-Research Diagnostic Criteria was used.

RESULTS

FTD is a multidimensional construct comprised at least 5 dimensions: disorganization, verbosity, poverty of speech, idiosyncratic thinking, and blocking. Clinical distractibility loadings split in 2 factors, disorganization and blocking, but it did not load on the mania-related (verbosity) factor. Attentional disturbance was significantly associated with each FTD factor except for idiosyncratic thinking, and these associations were largely independent from the severity of mania. The associations of FTDs with mania and attentional disturbances were independent from each other. FTD factors were not significantly associated with familial liability to bipolar or to schizophrenia.

CONCLUSIONS

Disorganization was the main FTD component. Distractibility was a core feature of FTD factors but it was not specifically accounted for by mania-related attentional impairment. The hypothesis of mutual interdependence between mania and attentional disturbance leading to FTDs could not be confirmed.

Methodological issues of genetic association studies

Genetic association studies explore the association between genetic polymorphisms and a certain trait, disease or predisposition to disease. It has long been acknowledged that many genetic association studies fail to replicate their initial positive findings. This raises concern about the methodological quality of these reports. Case-control genetic association studies often suffer from various methodological flaws in study design and data analysis, and are often reported poorly. Flawed methodology and poor reporting leads to distorted results and incorrect conclusions. Many journals have adopted guidelines for reporting genetic association studies. In this review, some major methodological determinants of genetic association studies will be discussed.