Assessment of Score Dependability of the Wisconsin Schizotypy Scales Using Generalizability Analysis

Development and Validation of the Chronic Gastritis Scale Under the System of Quality of Life Instruments for Chronic Diseases QLICD-CG Based on Classical Test Theory and Generalizability Theory

BACKGROUND AND AIM

Quality of life (QOL) for patients with chronic gastritis (CG) is of interest worldwide and disease-specific instruments are needed for clinical research and practice. This paper focused on the development and validation of the CG scale under the system of Quality of Life Instruments for Chronic Diseases (QLICD-CG) by the modular approach and both classical test theory and generalizability theory.

METHODS

The QLICD-CG was developed based on programmed decision procedures including multiple nominal and focus group discussions, in-depth interviews and quantitative statistical procedures. Based on the data measuring QOL 3 times before and after treatments from 142 inpatients with CG, the psychometric properties of the scale were evaluated with respect to validity, reliability and responsiveness employing correlation analysis, multi-trait scaling analysis, factor analyses, t tests and also G studies and D studies of generalizability theory analysis.

RESULTS

Correlation, multi-trait scaling and factor analyses confirmed good construct validity and criterion-related validity when using SF-36 as a criterion. The internal consistency α for all domains were higher than 0.70 except for the social domain (0.62). Test-retest reliability coefficients (Pearson r and intraclass correlations) for the overall score and all domains were higher than 0.80 except for the social domain (0.77), while they were ranging between 0.72 to 0.94 at facets level; The overall score and scores for all domains/facets had statistically significant changes (P<0.01) after treatments except for facets of social effects and sexual function with standardized response mean ranging from 0.04 to 1.03, but from 0.34 to 1.03 for the domain level scores. G-coefficients and index of dependability (Ф coefficients) confirmed the reliability of the scale further with more exact variance components, and decision information on number of items changing.

CONCLUSIONS

The QLICD-CG could be used as a useful instrument in assessing QoL for patients with CG, with good psychometric properties including validity, reliability and responsiveness and also several advantages.

Development and preliminary validation of the chronic obstructive pulmonary disease scale quality of life instruments for chronic diseases-chronic obstructive pulmonary disease based on classical test theory and generalizability theory

Quality of life (QOL) in patients with Chronic obstructive pulmonary disease (COPD) is a major global concern in respiratory care with the specific instruments used rarely being developed using a modular approach. This paper is aimed to develop the COPD scale of the system of QOL Instruments for Chronic Diseases (QLICD-COPD) by the modular approach based on Classical Test Theory and Generalizability Theory (GT). 114 inpatients with COPD were used to provide the data measuring QOL three times before and after treatments. The psychometric properties of the scale were evaluated with respect to validity, reliability and responsiveness employing correlation analysis, factor analyses, multi-trait scaling analysis, and also GT analysis. The Results showed that Multi-trait scaling analysis, correlation and factor analyses confirmed good construct validity and criterion-related validity with almost all correlation coefficients or factor loadings being above 0.40. The internal consistency α and test-retest reliability coefficients (Pearson r and Intra-class correlations ICC) for all domains except for the social domain were larger than 0.70, ranging between 0.70–0.86 with r = 0.85 for the overall. The overall score and scores for physical and the specific domains had statistically significant changes after treatments with moderate effect size SRM (standardized response mean) ranging from 0.32 to 0.44. All G-coefficients and index of dependability were all greater than 0.80 exception of social domain (0.546 and 0.500 respectively), confirming the reliability of the scale further. It concluded that the QLICD-COPD has good validity, reliability, and moderate responsiveness, and can be used as the QOL instrument for patients with COPD.

Development and validation of the peptic ulcer scale under the system of quality of life instruments for chronic diseases based on classical test theory and generalizability theory

BACKGROUND

Quality of life (QOL) for patients with Peptic ulcer disease (PUD) is of interest worldwide and disease-specific instruments are needed for clinical research and practice. This paper focus on the development and validation of the PUD scale under the system of quality of life instruments for chronic diseases (QLICD-PU) by the modular approach and both classical test theory and Generalizability Theory.

METHODS

The QLICD-PU is developed based on programmatic decision-making procedures, including multiple nominal and focus group discussions, in-depth interviews, and quantitative statistical procedures. Based on the data of 153 PUD inpatients, correlation analysis, factor analysis, t-test, and Generalizability Theory analysis (including generalizability study and decision study, ie. G-study and D-study) were used to assess the validity, reliability, and responsiveness of the scale.

RESULTS

When the popular scale health survey short form (SF-36) was used as the standard, correlation and factor analysis confirmed good construct validity and criterion-related validity of QLICD-PU. Except for the social domain (0.62), the internal consistency α of all domains is higher than 0.70. The overall score and the test-retest reliability coefficients (Pearson r and intra-class correlation ICC) in all domains are higher than 0.80 (0.77 in the social domain). After treatments, the overall score and scores of all domains have statistically significant changes (P < 0.01), except for social impact and sexual function scores. The SRM (Standardized response mean) of domain-level scores ranges from 0.34 to 1.03. The G coefficient and reliability index (Ф coefficient) further confirm the reliability of the scale through more accurate variance components and decision-making information about changes in the number of items.

CONCLUSIONS

The QLICD-PU can be used as a useful measurement to assess the quality of life of PUD patients with good psychometric characteristics and multiple advantages.

Impaired Facial Emotion Recognition in Individuals at Ultra-High Risk for Psychosis and Associations With Schizotypy and Paranoia Level

BACKGROUND

Patients with schizophrenia and individuals at ultra-high risk for psychosis (UHR) have been reported to exhibit impaired recognition of facial emotion expressions. This impairment has involved both inaccuracy and negative bias of facial emotion recognition. The present study aimed to investigate whether UHR individuals display both types of impaired facial emotion recognition and to explore correlations between these impairments and schizotypy, as well as paranoia levels, in these individuals.

METHODS

A total of 43 UHR individuals and 57 healthy controls (HC) completed a facial emotion recognition task consisting of 60 standardized facial photographs. To explore correlations, we assessed schizotypy using the Revised Physical Anhedonia Scale and Magical Ideation Scale and paranoia level using the Paranoia Scale and persecution/suspicious item of the Positive and Negative Syndrome Scale in UHR individuals.

RESULTS

Compared with HC, UHR individuals exhibited less accuracy for facial emotion recognition (70.6% vs. 75.6%, p=0.010) and a higher rate of "fear" responses for neutral faces (14.5% vs. 6.0%, p=0.003). In UHR individuals, inaccuracy was significantly correlated with schizotypy scores, but not with paranoia level. Conversely, "disgust" response for neutral faces was the only fear response correlated with paranoia level, and no threat-related emotion response correlated with schizotypy scores.

DISCUSSION

UHR individuals exhibited inaccuracy and negative bias of facial emotion recognition. Furthermore, schizotypy scores were associated with inaccuracy but not with negative bias of facial emotion recognition. Paranoia level was correlated with "disgust" responses for neutral faces but not with inaccuracy. These findings suggest that inaccuracy and negative bias of facial emotion recognition reflect different underlying processes, and that inaccuracy may be a vulnerability marker for schizophrenia.

Genome-Wide Association Study of Psychosis Proneness in the Finnish Population

The current study examined quantitative measures of psychosis proneness in a nonpsychotic population, in order to elucidate their underlying genetic architecture and to observe if there is any commonality to that already detected in the studies of individuals with overt psychotic conditions, such as schizophrenia and bipolar disorder. Heritability, univariate and multivariate genome-wide association (GWAs) tests, including a series of comprehensive gene-based association analyses, were developed in 4269 nonpsychotic persons participating in the Northern Finland Birth Cohort 1966 study with information on the following psychometric measures: Hypomanic Personality, Perceptual Aberration, Physical and Social Anhedonia (also known as Chapman's Schizotypia scales), and Schizoidia scale. Genome-wide genetic data was available for ~9.84 million SNPs. Heritability estimates ranged from 16% to 27%. Phenotypic, genetic and environmental correlations ranged from 0.04-0.43, 0.25-0.73, and 0.12-0.43, respectively. Univariate GWAs tests revealed an intronic SNP (rs12449097) at the TMC7 gene (16p12.3) that significantly associated (P = 3.485 × 10-8) with the hypomanic scale. Bivariate GWAs tests including the hypomanic and physical anhedonia scales suggested a further borderline significant SNP (rs188320715; P-value = 5.261 × 10-8, ~572 kb downstream the ARID1B gene at 6q25.3). Gene-based tests highlighted 20 additional genes of which 5 had previously been associated to schizophrenia and/or bipolar disorder: CSMD1, CCDC141, SLC1A2, CACNA1C, and SNAP25. Altogether the findings explained from 3.7% to 14.1% of the corresponding trait heritability. In conclusion, this study provides preliminary genomic evidence suggesting that qualitatively similar biological factors may underlie different psychosis proneness measures, some of which could further predispose to schizophrenia and bipolar disorder.

Reliability analysis of the Chinese version of the Functional Assessment of Cancer Therapy - Leukemia (FACT-Leu) scale based on multivariate generalizability theory

Background

The Functional Assessment of Cancer Therapy–Leukemia (FACT-Leu) scale, a leukemia-specific instrument for determining the health-related quality of life (HRQOL) in patients with leukemia, had been developed and validated, but there have been no reports on the development of a simplified Chinese version of this scale. This is a new exploration to analyze the reliability of the HRQOL measurement using multivariate generalizability theory (MGT). This study aimed to develop a Chinese version of the FACT-Leu scale and evaluate its reliability using MGT to provide evidence to support the revision and improvement of this scale.

Methods

The Chinese version of the FACT-Leu scale was developed by four steps: forward translation, backward translation, cultural adaptation and pilot-testing. The HRQOL was measured for eligible inpatients with leukemia using this scale to provide data. A single-facet multivariate Generalizability Study (G-study) design was demonstrated to estimate the variance–covariance components and then several Decision Studies (D-studies) with varying numbers of items were analyzed to obtain reliability coefficients and to understand how much the measurement reliability could be vary as the number of items in MGT changes.

Results

One-hundred and one eligible inpatients diagnosed with leukemia were recruited and completed the HRQOL measurement at the time of admission to the hospital. In the G-study, the variation component of the patient-item interaction was largest while the variation component of the item was the smallest for the four of five domains, except for the leukemia-specific (LEUS) domain. In the D-study, at the level of domain, the generalizability coefficients (G) and the indexes of dependability (Ф) for four of the five domains were approximately equal to or greater than 0.80 except for the Emotional Well-being (EWB) domain (>0.70 but <0.80). For the overall scale, the composite G and composite Ф coefficients were greater than 0.90. Based on the G coefficient and Ф coefficient, two decision options for revising this scale considering the number of items were obtained: one is a 37-item version while the other is a 45-item version.

Conclusion

The Chinese version of the FACT-Leu scale has good reliability as a whole based on the results of MGT and the implementation of MGT could lead to more informed decisions in complex questionnaire design and improvement.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0664-2) contains supplementary material, which is available to authorized users.

Normative data of the Magical Ideation Scale from childhood to adulthood in an Italian cohort

The assessment of schizotypy allows to identify people at risk to develop psychosis. For this purpose, psychometric tools have been developed, such as the Magical Ideation Scale (MIS). This scale investigates attenuated forms of thought transmission experiences, thought withdrawal and aberrant beliefs, related to positive schizotypy. This study aims at providing an Italian version of the MIS and its normative data in the general population from childhood to adulthood, being the first study evaluating subjects under 17year-old. The Italian MIS version was translated by three independent operators and administered to 1378 non-clinical participants, stratified into four age groups (i.e., 8-13, 14-17, 18-24 and 25-34). The unidimensionality of the scale was supported, and its internal consistency was satisfactory (i.e., ordinal Cronbach's αs ranging from 0.86 to 0.90 in different age groups), as well as test-retest reliability (i.e., 1-month ICC of 0.82 in a retested sub-sample). Normative data for the age groups were provided. Specific gender and age-related differences in MIS score were found, i.e. females scored higher than males in the 25-34 age group, which in general, as a group, scored lower than all the other age groups. This study provided evidence of reliability for the Italian version of the MIS in childhood and adolescence, for the first time, as well as in adulthood, showing specific gender and age effects in the early adult cohort.

Development and validation of the nasopharyngeal cancer scale among the system of quality of life instruments for cancer patients (QLICP-NA V2.0): combined classical test theory and generalizability theory

OBJECTIVES

This research was designed to develop a nasopharyngeal cancer (NPC) scale based on quality of life (QOL) instruments for cancer patients (QLICP-NA). This scale was developed by using a modular approach and was evaluated by classical test and generalizability theories.

METHODS

Programmed decision procedures and theories on instrument development were applied to create QLICP-NA V2.0. A total of 121 NPC inpatients were assessed using QLICP-NA V2.0 to measure their QOL data from hospital admission until discharge. Scale validity, reliability, and responsiveness were evaluated by correlation, factor, parallel, multi-trait scaling, and t test analyses, as well as by generalizability (G) and decision (D) studies of the generalizability theory.

RESULTS

Results of multi-trait scaling, correlation, factor, and parallel analyses indicated that QLICP-NA V2.0 exhibited good construct validity. The significant difference of QOL between the treated and untreated NPC patients indicated a good clinical validity of the questionnaire. The internal consistency (α) and test-retest reliability coefficients (intra-class correlations) of each domain, as well as the overall scale, were all >0.70. Ceiling effects were not found in all domains and most facets, except for common side effects (24.8 %) in the domain of common symptoms and side effects, tumor early symptoms (27.3 %) and therapeutic side effects (23.2 %) in specific domain, whereas floor effects did not exist in each domain/facet. The overall changes in the physical and social domains were significantly different between pre- and post-treatments with a moderate effective size (standard response mean) ranging from 0.21 to 0.27 (p < 0.05), but these changes were not obvious in the other domains, as well as in the overall scale. Scale reliability was further confirmed by G coefficients and index of dependability, with more exact variance components based on generalizability theory.

CONCLUSIONS

QLICP-NA V2.0 exhibited reasonable degrees of validity, reliability, and responsiveness. However, this scale must be further improved before it can be used as a practical instrument to evaluate the QOL of NPC patients in China.

The Chapman psychosis-proneness scales: Consistency across culture and time

The purpose of the present study was to examine the factor structure and the temporal stability of the Chapman psychosis-proneness scales in a representative sample of nonclinical Chinese young adults. The four psychosis-proneness scales evaluated were the Perceptual Aberration (PAS), Magical Ideation (MIS), revised Social Anhedonia (RSAS), and revised Physical Anhedonia (RPAS) scales. The sample consisted of 1724 young adults with a mean age of 18.8 years (S.D. = 0.84). The results of the confirmatory factor analyses indicated that the best fitting model was a two-factor model with positive schizotypy (PER and MIS) scales and negative schizotypy (RSAS and RPAS) scales. The data add to the growing literature indicating that the measurement of schizotypal traits is consistent across cultures. In addition, the results support the measurement invariance of the Chapman psychosis-proneness scales across time, i.e., there was ample evidence of test-retest reliability over a test interval of 6 months.

Predicting symptoms of depression from social anhedonia and emotion regulation

The literature examining social anhedonia, emotion regulation, and symptoms of depression in psychiatric inpatients has been limited. However, some studies have shown that difficulties in emotion regulation and social anhedonia were independently associated with depression. The current study attempted to examine the effects of these two potential predictors of unipolar depressed mood. Fifty-nine (73% female) psychiatric inpatients were given the measures of emotion regulation, symptoms of anxiety and depression, and social anhedonia. Results showed that difficulties in emotion regulation, specifically dysfunctional emotion regulation strategies and emotional clarity, served as significant predictors of depressive symptoms above and beyond contributions from social anhedonia. These results highlight the importance of attending to emotion regulation in the study and treatment of depression in inpatient samples.

Development and validation of the irritable bowel syndrome scale under the system of quality of life instruments for chronic diseases QLICD-IBS: combinations of classical test theory and generalizability theory

PURPOSE

This paper is aimed to develop the irritable bowel syndrome (IBS) scale of the system of Quality of Life Instruments for Chronic Diseases (QLICD-IBS) by the modular approach and validate it by both classical test theory and generalizability theory.

METHODS

The QLICD-IBS was developed based on programmed decision procedures with multiple nominal and focus group discussions, in-depth interview, and quantitative statistical procedures. One hundred twelve inpatients with IBS were used to provide the data measuring QOL three times before and after treatments. The psychometric properties of the scale were evaluated with respect to validity, reliability, and responsiveness employing correlation analysis, factor analyses, multi-trait scaling analysis, t tests and also G studies and D studies of generalizability theory analysis.

RESULTS

Multi-trait scaling analysis, correlation, and factor analyses confirmed good construct validity and criterion-related validity when using SF-36 as a criterion. Test-retest reliability coefficients (Pearson r and intra-class correlation (ICC)) for the overall score and all domains were higher than 0.80; the internal consistency α for all domains at two measurements were higher than 0.70 except for the social domain (0.55 and 0.67, respectively). The overall score and scores for all domains/facets had statistically significant changes after treatments with moderate or higher effect size standardized response mean (SRM) ranging from 0.72 to 1.02 at domain levels. G coefficients and index of dependability (Ф coefficients) confirmed the reliability of the scale further with more exact variance components.

CONCLUSIONS

The QLICD-IBS has good validity, reliability, responsiveness, and some highlights and can be used as the quality of life instrument for patients with IBS.

Development and validation of the coronary heart disease scale under the system of quality of life instruments for chronic diseases QLICD-CHD: combinations of classical test theory and Generalizability Theory

Background

Quality of life (QOL) for patients with coronary heart disease (CHD) is now concerned worldwide with the specific instruments being seldom and no one developed by the modular approach.

Objectives

This paper is aimed to develop the CHD scale of the system of Quality of Life Instruments for Chronic Diseases (QLICD-CHD) by the modular approach and validate it by both classical test theory and Generalizability Theory.

Methods

The QLICD-CHD was developed based on programmed decision procedures with multiple nominal and focus group discussions, in-depth interview, pre-testing and quantitative statistical procedures. 146 inpatients with CHD were used to provide the data measuring QOL three times before and after treatments. The psychometric properties of the scale were evaluated with respect to validity, reliability and responsiveness employing correlation analysis, factor analyses, multi-trait scaling analysis, t-tests and also G studies and D studies of Genralizability Theory analysis.

Results

Multi-trait scaling analysis, correlation and factor analyses confirmed good construct validity and criterion-related validity when using SF-36 as a criterion. The internal consistency α and test-retest reliability coefficients (Pearson r and Intra-class correlations ICC) for the overall instrument and all domains were higher than 0.70 and 0.80 respectively; The overall and all domains except for social domain had statistically significant changes after treatments with moderate effect size SRM (standardized response mea) ranging from 0.32 to 0.67. G-coefficients and index of dependability (Ф coefficients) confirmed the reliability of the scale further with more exact variance components.

Conclusions

The QLICD-CHD has good validity, reliability, and moderate responsiveness and some highlights, and can be used as the quality of life instrument for patients with CHD. However, in order to obtain better reliability, the numbers of items for social domain should be increased or the items’ quality, not quantity, should be improved.

Assessing the Dependability of Drinking Motives via Generalizability Theory

This study assessed the score reliability of the Drinking Motives Questionnaire-Revised (DMQ-R) via generalizability theory. Participants (n = 367 college students) completed the DMQ-R at three time points. Across subscale scores, persons, persons × occasions, and persons × items interactions accounted for meaningful variance. Findings illustrate advantages of generalizability theory-based techniques.

Psychometric properties and validity of short forms of the Wisconsin Schizotypy Scales in two large samples

The Wisconsin Schizotypy Scales (WSS) have been widely used in the study of clinical and non-clinical samples. However, researchers often find the length of the scales prohibitive. The present study examined the reliability and validity of recently developed 15-item short forms of the Perceptual Aberration, Magical Ideation, Physical Anhedonia, and Revised Social Anhedonia Scales in two large samples of non-clinically ascertained young adults. The scales demonstrated good reliability and correlated highly with the original scales. The validity of the scales was assessed by comparing the association of the original and shortened WSS with interview measures of psychotic-like and schizophrenia-spectrum symptoms and impaired functioning, as well as with questionnaire measures of personality and social impairment. The associations of the shortened WSS with the interview and questionnaire measures were comparable in terms of statistical significance and effect size with the associations of the original scales. The present findings provide the first demonstration of the validity of the shortened WSS and support their use in the study of schizotypy.