Effects of cerebral hemispheric laterality on the span of apprehension of schizophrenic and healthy subjects

[Prospective description of the course of psychopathological symptoms in schizophrenia: evaluation of the short form of the Eppendorf Schizophrenia Inventory]

BACKGROUND

The Eppendorf Schizophrenia Inventory (ESI-K) is a self-assessment procedure which can now be considered as the standard procedure in the diagnostics of schizophrenia. It has been evaluated in many studies and is widely used in research and clinical treatment. In contrast little is known about the psychometric characteristics of the short form of the ESI (ESI-K) which was designed in particular for prospective descriptive courses.

MATERIALS AND METHODS

The ESI-K was completed for 40 patients with schizophrenia undergoing complete inpatient psychiatric treatment together with the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions (CGI) form and the Nurses' Observation Scale for Inpatient Evaluation (NOSIE). Of the patients 31 participated in a total of 4 measurements at 1-week intervals.

RESULTS

The reliability (Cronbachs α) of the ESI-K was high at all measurement time points and was comparable to the reliability of the standard version. The reliability of the PANSS was roughly the same level but that of the NOSIE was poor. The ESI-K correlated in particular with cognitive syndrome and the positive syndrome of the PANSS. All four instruments showed a decrease in scores over the observational time period which indicated a decline in the psychopathological symptoms.

CONCLUSIONS

The ESI-K is a valid time-saving procedure for documentation of the course of symptoms in patients with schizophrenia. It reflects clinically relevant aspects from the spectrum of psychotic symptoms.

Das Eppendorfer Schizophrenie-Inventar (ESI) als methodischer Ansatz in der High-Risk- und Schizotypieforschung

Zusammenfassung. Ergebnisse früherer Untersuchungen geben Anlass zu Zweifeln an der diagnostischen Validität vieler in der Schizotypieforschung eingesetzten psychometrischen Standardverfahren. Das kürzlich vorgelegte Eppendorfer Schizophrenie-Inventar (ESI) erfasst eine Reihe von psychopathologischen Symptomen, die sich in direkten Vergleichen mit anderen klinischen Gruppen wiederholt als besonders charakteristisch für Schizophrenie erwiesen haben. In der vorliegenden Evaluationsstudie sollte die Eignung des ESI für Schizotypiestudien geprüft werden. Dazu wurden N = 57 gesunde Erwachsene mit dem ESI sowie zu Vergleichszwecken mit der Perceptual Aberration Scale, dem Continuous Performance Test und der Span of Apprehension Task untersucht. Es fanden sich hypothesengemäß signifikante Korrelationen zwischen dem ESI und allen eingesetzten Vergleichsverfahren. Diese Befunde stützen die Annahme, dass das ESI schizotypische Persönlichkeitsaspekte bei klinisch unauffälligen Probanden erfasst. Seine Verwendung in High-Risk- und Schizotypiestudien erscheint vielversprechend.

Finding of abnormal scanning behavior in the Span of Apprehension task in schizophrenia but diagnostic non-specificity of sum scores

Deficits in the Span of Apprehension (SOA) task have been discussed controversially as a trait marker of schizophrenia. The task was administered to 47 schizophrenia and 48 depressed patients as well as to 46 controls. Results indicate a non-specificity of the SOA sum scores but differential abnormalities in spatial visual processing.

Comparison of three computer-administered cognitive tasks as putative endophenotypes of schizophrenia

It has been repeatedly demonstrated that individuals with schizotypal personality features (SPF) exhibit similar endophenotypic traits as persons with schizophrenia. Less research has compared the relative sensitivity of different endophenotypes in the same sample of individuals with SPF. Fourteen university students with SPF (mean age 20.5+/-1.6; 43% male) and 26 controls (mean age 20.3+/-1.1; 31% male) were defined by the Abbreviated Schizotypal Personality Questionnaire (SPQ-B). All participants reported no known biological relative with schizophrenia. Participants completed three computer-administered cognitive tasks: a 6-min degraded-stimuli A-X Continuous Performance Test (CPT), the Wisconsin Card Sort Test (WCST), and a Span of Apprehension (SOA) task (6- and 12-letter arrays). On the CPT, only omission errors resulted in a statistically significant group difference, U=115.5, p=.05, Cohen's d=0.54 (medium effect size), with the SPF group (mean errors: 3.43+/-3.28) making more omission errors than controls (mean errors: 1.88+/-2.66). Notably, 46% of the controls had no omission errors, compared to 14% of the SPF group. The only SPQ-B factor score to show a statistically significant linear relationship with CPT omission errors was the Cognitive-Perceptual factor (rs=.33, p=.04). Group differences on performance indices from the SOA and WCST did not approach statistical significance. Based on performance from the community-identified schizotypes, results suggest that performance on the CPT may represent a more robust endophenotype of schizophrenia, compared to the SOA and WCST.

Eppendorfer Schizophrenie-Inventar (ESI) vs. Frankfurter Beschwerde-Fragebogen (FBF)

This study is the first to directly compare two clinical questionnaires which are both aimed at self-experienced cognitive dysfunctions of schizophrenia: Eppendorf Schizophrenia Inventory (ESI) and Frankfurt Complaint Questionnaire (FCQ). Evaluated were (a) diagnostic validity, (b) psychometric properties, (c) scale intercorrelations, and (d) factor analytic stability. Ad (a): schizophrenic subjects (n=36) show highly significant increases in the ESI scales and sum score when compared to other clinical groups (patients with depression, alcohol dependence, or obsessive-compulsive disorder, n>30, respectively); on the other hand, the FCQ yields no systematic group differences. Ad (b): mean of reliability coefficients (Cronbach alpha) of the ESI scales is r(tt)=0.86, mean of reliability coefficients of the FCQ scales is significantly lower. Ad (c): the mean intercorrelation between ESI and FCQ scales amounts to r(xy)=0.56 (minimum 0.29, maximum 0.73), corresponding to an average shared variance of about 31%. Ad (d): factor analysis yielded an ESI factor and a FBF factor; one-way ANOVA with the factor scores confirms the diagnostic validity of the ESI.

CONCLUSIONS

ESI and FCQ measure essentially different aspects of schizophrenic psychopathology. Regarding reliability and diagnostic validity, the ESI is superior to the FCQ.

Abnormal subjective experiences of schizophrenia: evaluation of the Eppendorf Schizophrenia Inventory

The Eppendorf Schizophrenia Inventory (ESI) is a new clinical questionnaire aimed at self-experienced cognitive disturbances that are considered to be diagnostically specific for schizophrenia. Two ESI validation studies are presented in this report. The aim of study I was to search for objective correlates of the ESI in 100 schizophrenic inpatients. In study II, the diagnostic validity of the ESI was examined by group comparisons (inpatients with first episode or chronic schizophrenia, alcoholism, depression, or obsessive-compulsive disorder, and healthy adults). Study I yielded numerous plausible correlations between ESI subscales and other clinical scales, neuropsychological tests, psychopathological interview data, and neurological symptoms. Study II supported the diagnostic validity of the ESI. A confirmatory factor analysis conducted with the combined schizophrenic sample from both studies corroborated the assumed factor structure. These results confirm the reliability and validity of the ESI.

Incipient neuroleptic malignant syndrome with quetiapine/paroxetine combination treatment: atypical presentation and early, successful rechallenge with olanzapine

A 26-year-old caucasian male developed incipient neuroleptic malignant syndrome (NMS) during the course of paranoid schizophrenia with catatonic signs at admission, while on quetiapine/paroxetine combination treatment. The clinical presentation was "atypical", but increased creatine kinase levels and positive myoglobinemia were highly suggestive of the diagnosis. Of note, the patient was successfully rechallenged with olanzapine. The implications of the drug regimen and of the catatonic presentation are discussed.

Accelerated age-related decline of visual information processing in first-degree relatives of persons with schizophrenia

A recent cross-sectional study suggested that persons with schizophrenia experience an accelerated age-related decline in performance on the Span of Apprehension task, a visual information processing paradigm. However, this study was not able to determine if such decline was primarily related to genetic loading for schizophrenia, as the decline may have been related to chronic neuroleptic use or other confounds found when studying persons with schizophrenia directly. To help address this question, the current study examined healthy first-degree relatives of persons with schizophrenia over a wide age range to investigate whether such age effects may be related to genetic loading for schizophrenia. Twenty-eight healthy first-degree relatives of persons with schizophrenia (ages 21-72) and 31 healthy controls (ages 19-75) were evaluated using the Span of Apprehension task with cross-sectional methodology. Results replicated and extended the earlier report examining persons with schizophrenia, as the data indicated a statistically significant accelerated age-related decline in performance in the relatives. While the study is limited by cross-sectional methodology, it suggests a genetically driven, age-related decline in visual information processing related to schizophrenia and informs future longitudinal studies that can more definitively address such a possibility.

Psychometrische Erfassung charakteristischer subjektiver Zeichen und Symptome der Schizophrenie mit dem Eppendorfer Schizophrenie-Inventar (ESI)

Zusammenfassung. Theoretischer Hintergrund: Das Eppendorfer Schizophrenie-Inventar (ESI) erfasst charakteristische subjektive Zeichen und Symptome der Schizophrenie und kann so zur Verbesserung der Diagnostik beitragen, z.B. bei der Früherkennung und -behandlung psychotischer Störungen. In der vorliegenden Arbeit werden zwei Validierungsstudien zum ESI präsentiert. Fragestellung und Methode: Studie I hatte das Ziel, nach objektivierbaren Korrelaten der mit dem ESI erfassten subjektiven Phänomene zu suchen; N = 100 akut erkrankte Schizophrene wurden eingeschlossen. In Studie II wurde die diagnostische Spezifizität des ESI durch Gruppenvergleiche geprüft (37 ersterkrankte und 30 chronifizierte Schizophrene, 31 Alkoholkranke, 37 Depressive, 34 Zwangskranke, 30 Gesunde). Ergebnisse und Schlussfolgerungen: Studie I erbrachte zahlreiche plausible Korrelationen zwischen ESI-Skalen und anderen klinischen Fragebögen, neuropsychologischen Tests, fremdbeurteilten psychopathologischen und neurologischen Symptomen. Studie II bestätigte die differentialdiagnostische Validität des ESI.