Bifactor Model Research Articles

Reliability and validity of communal narcissism scale in Chinese university students

ObjectiveThe Communal Narcissism Inventory (CNI) was applied to college students to explore the factor structure of the scale under the background of Chinese culture, and to test its reliability and validity. Methods949 university students were measured with CNI scale. The prosocial behavior scale, self-esteem scale and Big Five personality scale were used to verify the reliability and validity of the Chinese version of CNI scale. Three weeks later, 90 college students were randomly selected for retesting. ResultsThe bifactor model is more suitable for university students than the single-factor model. Cronbach'α are 0.92, 0.91 and 0.86. Exploratory factor analysis and confirmatory factor analysis show that the project load is between 0.52 and 0.84, the correlation coefficient is significant, and there is a good fitting index. ConclusionThe Chinese version of CNI has reasonable reliability and validity under the Chinese cultural background, and can be used for the evaluation and research of communal narcissism of domestic university students.

Examining the Development of Peer Attachment Based on Parental Attachment, and Collaborative Impacts on Mental Health among Japanese Youth

This study aimed at confirming the factor structure of the Japanese version of Inventory of Parent and Peer Attachment (IPPA) for peers. Furthermore, it examined whether or not peer attachment is significantly influenced by father and/or mother attachment, and to see whether father and mother attachment affects mental health directly and/or indirectly via peer attachment for each gender among Japanese youth. The targets of this study were 433 (men: 149, women: 284) Japanese college students who completed every item of the Japanese version of father, mother, and peer IPPAs, as well as Clinical Outcomes in Routine Evaluation – Outcome Measure (CORE-OM) to evaluate their mental health. Confirmatory Factor Analysis (CFA) was conducted to confirm the factor structure of the Japanese version of peer IPPA. Structural Equation Modelling (SEM) was utilized to see whether or not peer attachment is significantly influenced by father and/or mother attachment, and whether or not peer attachment mediates between parental IPPA and mental health. A bi-factor model, constituted by one general factor and three specific factors forming the original IPPA developed by Armsden & Greenberg (1989), was supported by excluding one item from the specific factor Alienation. SEM revealed that the mental health of both male and female respondents was significantly influenced by peer attachment. Among males, its platform was built by attachment only to the father, whereas among females, it was built by both father and mother attachment.

Understanding the Within- and Between-Person Structure of Daily Psychopathology Among Adolescents and Young Adults.

Previous investigations on the underlying structure of psychopathology symptoms primarily focused at the between-person level and among adult samples. This study used two independent Canadian samples with month-long daily diary designs to investigate daily psychopathology structure at both within- and between-person level among adolescents (n = 99, 2,132 daily reports) and young adults (n = 313, 6,431 and 4,018 daily reports at each wave). Four mainstream types of psychopathology structure were compared based on a comprehensive set of standards. The results suggest that the general factor of psychopathology (p factor) derived from the higher-order and bifactor models performed similarly well at both within- and between-person levels, while the specific factors estimated in the bifactor models demonstrated low reliability and consistency over time. Psychopathology manifests as multidimensional at the within-person level but unidimensional at the between-person level. The current findings inform the development of future prevention and intervention programs by supporting the adoption of transdiagnostic treatment that addresses multiple psychopathology symptoms with a holistic approach.

Evaluating the factor structure of the pregnancy-related anxiety scale: implications for maternal and infant wellbeing

ABSTRACT Aims/Background Although the Pregnancy-Related Anxiety Scale – also referred to as the Pregnancy-Related Thoughts Scale (PRT) – is one of the most widely utilised measures of pregnancy-related anxiety (PrA), there is limited research exploring its factor structure and psychometric properties. The present study sought to (a) explore the factor structure of the PRT and (b) examine whether specific dimensions of PrA differentially predict postpartum outcomes. Design/Methods A community sample of pregnant women (N = 159) was recruited from a Midwestern city in the United States and completed the PRT alongside other self-report measures of stress and maternal health and mood during pregnancy. Participants also completed measures of maternal health and mood, as well as parenting/infant outcomes, at 1- and 6-months postpartum. Results Results provided support for a bifactor model with two unique dimensions of the PRT capturing baby- and self-focused concerns, respectively. Maternal self-focused PrA uniquely predicted postpartum internalising problems (β = .22), worse physical health (β = -.27), and impaired mother-infant bonding (β = .19) when controlling for baby-focused and general PrA. Conclusion Findings highlight the utility of screening for specific dimensions of PrA to promote both maternal and infant wellbeing following childbirth. Specifically, evidence suggests that screening for self-focused PrA, above and beyond baby-focused PrA, might facilitate prevention and intervention efforts and allow researchers to better understand antecedents and consequences of unique facets of PrA.

Polygenic Risk Underlies Youth Psychopathology and Personalized Functional Brain Network Topography.

Functional brain networks are associated with both behavior and genetic factors. To uncover clinically translatable mechanisms of psychopathology, it is critical to define how the spatial organization of these networks relates to genetic risk during development. To determine the relationship between transdiagnostic polygenic risk scores (PRSs), personalized functional brain networks (PFNs), and overall psychopathology (p-factor) during early adolescence. The Adolescent Brain Cognitive Development (ABCD) Study is an ongoing longitudinal cohort study of 21 collection sites across the United States. Here, we conduct a cross-sectional analysis of ABCD baseline data, collected 2017-2018. The ABCD Study ® is a multi-site community-based study. The sample is largely recruited through school systems. Exclusion criteria included severe sensory, intellectual, medical, or neurological issues that interfere with protocol and scanner contraindications. Split-half subsets were used for cross-validation, matched on age, ethnicity, family structure, handedness, parental education, site, sex, and anesthesia exposure. Polygenic risk scores of transdiagnostic genetic factors F1 (PRS-F1) and F2 (PRS-F2) derived from adults in Psychiatric Genomic Consortium and UK Biobanks datasets. PRS-F1 indexes liability for common psychiatric symptoms and disorders related to mood disturbance; PRS-F2 indexes liability for rarer forms of mental illness characterized by mania and psychosis. (1) P-factor derived from bifactor models of youth- and parent-reported mental health assessments. (2) Person-specific functional brain network topography derived from functional magnetic resonance imaging (fMRI) scans. Total participants included 11,873 youths ages 9-10 years old; 5,678 (47.8%) were female, and the mean (SD) age was 9.92 (0.62) years. PFN topography was found to be heritable (N=7,459, 57.06% of vertices h 2 p FDR <0.05, mean h 2 =0.35). PRS-F1 was associated with p-factor (N=5,815, r=0.12, 95% CI [0.09-0.15], p<0.001). Interindividual differences in functional network topography were associated with p-factor (N=7,459, mean r=0.12), PRS-F1 (N=3,982, mean r=0.05), and PRS-F2 (N=3,982, mean r=0.08). Cortical maps of p-factor and PRS-F1 regression coefficients were highly correlated (r=0.7, p=0.003). Polygenic risk for transdiagnostic adulthood psychopathology is associated with both p-factor and heritable PFN topography during early adolescence. These results advance our understanding of the developmental drivers of psychopathology.

The structure, development, and etiology of observed temperament during middle childhood.

Investigating the structure and etiology of temperament is key to understanding how children interact with the world (Kagan, 1994). Although these topics have yielded an abundance of research, fewer studies have employed observational data during middle childhood, when unique environmental challenges could influence temperament development. To address this gap, Israeli twin children were observed at Age 6.5 (N = 1,083, 564 families; 50.6% females) and again at Age 8-9 (N = 768, 388 families; 52.0% females; 611 children from 322 families had data from both ages). Temperament was assessed globally by trained coders and, at Age 8-9, also by the experimenter who interacted with the child. We examined whether Rothbart et al.'s (2000) three-factor model, according to which temperament includes the domains negative affect, positive affect/surgency, and effortful control, emerges from the data. In addition, we considered a bifactor model, where a fourth global factor accounts for all behaviors' commonality. Across the two ages and rating methods, confirmatory factor analyses supported the bifactor model. The global factor's loadings suggested that it reflects children's expressiveness. Adding this factor changed the associations between the other factors and enabled differentiation between surgency and positive affect. This suggests that in observational settings that capture temperament impressions holistically, children's expressiveness affects other traits' behavioral displays. Twin models revealed genetic influences for most traits. Importantly, twin models revealed shared-environmental influences for negative affect and expressiveness, which modestly contributed to temperament consistency across ages. These findings shed light on temperament traits' interrelatedness and stress the importance of the shared environment to temperament development during middle childhood. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

An Examination of the Psychometric Properties of the Exercise Identity Scale and Its Adaptation to Physical Activity

ABSTRACT This study investigated whether exercise and physical activity identity are conceptually distinct factors. Undergraduate students (N = 647; M age = 19.54 ± 1.86 years; 61% female) completed an online survey including the Exercise Identity Scale and a modified physical activity version. Confirmatory factor analysis largely supported a 4-factor model consisting of physical activity and exercise role identity and beliefs. Despite some evidence of multidimensionality from a bifactor model, 86% of the variance was captured by a general identity factor, indicating unidimensionality across both domains (i.e. physical activity versus exercise identity) and dimensions (i.e. role identity versus beliefs). Collectively, these findings suggest that exercise and physical activity identity may represent a unitary construct. Further research is needed to determine the best factor structure for these identities, especially in more diverse samples. Researchers are strongly encouraged to select an identity instrument that is congruent with their outcome of interest moving forward.

Leveraging bifactor modeling to test prospective direct and indirect effects of adolescent alcohol use and externalizing symptoms on the development of task-general executive functioning

Leveraging bifactor modeling to test prospective direct and indirect effects of adolescent alcohol use and externalizing symptoms on the development of task-general executive functioning

Developing an Adaptive Behavior Construct from National Longitudinal Transition Study-2 (NLTS2) Data

ABSTRACT The current study aimed to develop an adaptive behavior construct using National Longitudinal Transition Study-2 (NLTS2) data. The parent survey data gathered at Wave 1 was used to create an adaptive behavior construct. A bifactor model with three subdomains of conceptual, social, and practical skills with a total of 21 items was developed using confirmatory factor analysis (CFA) with acceptable fit indices (RMSEA = 0.049, CFI = 0.977, TLI = 0.971). The total score from the adaptive behavior construct was statistically significantly different across groups of youths with different levels of intellectual disability. The adaptive behavior construct created from the current study will allow for a series of research involving adaptive behavior variables within NLTS2 data.

Validation of the Attitudes toward Lying to People with Dementia (ALPD) Questionnaire among Social Workers in Spain.

Gerontological interventions should address the various geriatric syndromes suffered by the elderly, such as neurodegenerative diseases. Therapeutic lying is an effective and humanizing strategy to deal with dementia, used by various disciplines in the social and healthcare fields. This intervention strategy is made up of all the different responses to reality that are given to a person with cognitive impairment. This study analyzes the validity of the Spanish adaptation of the Attitudes toward Lying to People with Dementia (ALPD) questionnaire, given to 253 social workers who directly and indirectly intervened with older people suffering from cognitive impairment in public and private centers in Spain during the year 2022. The results of the validity and reliability analyses support the psychometric quality of ALPD for use in Spanish social workers. The statistical results indicate a good fit of the bifactor model (person-focused and lie-focused) and show the questionnaire to be reliable, with adequate psychometric properties. The article concludes with a discussion of practical, formative, and ethical challenges for social work in the field of geriatric services.

Exploring Associations of Somatic Symptom Disorder with Personality Dysfunction and Specific Maladaptive Traits

Introduction: According to ICD-11, personality disorders (PDs) are defined by the severity of self and interpersonal dysfunction in terms of personality functioning (PF) and an optional assessment of specific maladaptive personality trait expressions. Also, somatoform disorders are replaced by somatic symptom disorder (SSD). This study examines associations using the novel diagnostic criteria of SSD in an unselected primary care sample, PF, and maladaptive traits in patients with and without SSD. Methods: An anonymized cross-sectional study was conducted. A questionnaire including SSD-12 (Somatic Symptom Disorder B Criteria Scale-12) and PHQ-15 (Patient Health Questionnaire-15), LPFS-BF 2.0 (Level of Personality Functioning Scale – Brief Form) and PID-5BF+M (Modified Personality Inventory for DSM-5 – Brief Form Plus) was used. A bifactor (S-1) model was calculated with PF (reference for general factor) and personality traits (specific factors) to estimate associations between PF, specific maladaptive personality traits, and SSD. Differences in personality scales between SSD and non-SSD patients were calculated with the Mann-Whitney U test. Results: A total of 624 patients in six general practices participated (mean age 47 years; 60.4% female). SSD-12 and PHQ-15, respectively, showed significant associations with PF (γ = 0.51; γ = 0.48; p < 0.001), negative affectivity (γ = 0.50; γ = 0.38, p < 0.001) and psychoticism (γ = 0.29; γ = 0.28; p < 0.010). Besides, SSD-12 was significantly associated with disinhibition (γ = −0.38; p < 0.010) and anankastia (γ = −0.16; p < 0.010). Patients with SSD showed significantly impaired PF and maladaptive traits in all scales (p < 0.001). Conclusion: Impaired PF explains moderate to large amounts of the SSD symptoms and maladaptive personality traits negative affectivity, psychoticism, disinhibition, and anankastia show specific associations beyond PF. An in-depth understanding of these relations might be helpful to improve doctor-patient communication and treatment in SSD.

Evaluation of psychometric characteristics of employee motivation in the workplace

Researchers constantly look for the ideal motivating factors in various countries, industries, and sectors, due to its multilateral dimension, which includes employees, managers, organizational policies and practices, and the way that the very dynamic external environmental factors influence them. Self-Determination Theory of motivation proposed by Edward Deci and Richard Ryan, embraces a holistic approach to human motivation which started by identifying several motivational styles and has been implemented in different fields of workplace motivation and management This paper aims to emphasize the importance of examining the psychometric characteristics of the employee motivation scale in the workplace, relying on some bifactor model ancillary indices. The degree of motivation was measured through the Multidimensional Work Motivation Scale (MWMS), based on Self-Determination Theory (SDT). The data were collected from a self-report questionnaire addressed to 658 employees from various businesses and institutions in the Korça region, in Albania. The ancillary indices, derived from the standardized loadings of a confirmatory bifactor model, provide a more comprehensive overview of the psychometric characteristics of the measurement instrument. The study showed that treating the MWMS as unidimensional within a multidimensional construct may cause only a small bias. However, its interpretation seems questionable. On the other hand, the added value of some subscale scores should be considered and can be statistically appropriate for interpretation, helping applied researchers. This study contributes to the field by highlighting the necessity of scrutinizing the psychometric properties of the employee motivation scale and demonstrates the utility of employing bifactor model ancillary indices for a more nuanced understanding. For the first time in Albania, we have a measurement instrument related to the motivation of employees in the workplace, which enjoys good psychometric characteristics.

Unidimensional or multidimensional? Revisiting the psychometrics of PHQ-9 and EPDS using bifactor model and item response theory in 2939 Chinese perinatal women

BackgroundPerinatal depression often goes undetected and untreated in low- and middle-income countries like China. Reliable screening tools can improve this situation. The Patient Health Questionnaire-9 (PHQ-9) and the Edinburgh Postnatal Depression Scale (EPDS), two widely used tools, often exhibit inconsistent factor structures, leading to debates regarding their unidimensionality versus multidimensionality and casting doubts on their psychometric properties. MethodsOur study aimed to assess the utility of PHQ-9 and EPDS in Chinese perinatal women and to address the debate by employing the bifactor model and item response theory (IRT). We enrolled 2939 perinatal women from a maternity and infant health hospital serving all 16 districts of Shanghai. The bifactor model was used to examine the factor structure of PHQ-9 and EPDS, while IRT analysis evaluated the psychometric properties. ResultsThe indices derived from the bifactor model indicated that both PHQ-9 and EPDS should be used as unidimensional measurements. All items in PHQ-9 and EPDS showed adequate discriminative ability and difficulty, but certain items require further refinement. PHQ-9 demonstrated better measurement precision at high levels of latent depression than EPDS. LimitationsThese findings might not generalize to perinatal women in impoverished areas. The absence of clinical diagnoses limited the exploration of sensitivity and specificity. ConclusionsPHQ-9 and EPDS are effective tools for detecting depression in Chinese perinatal women and should be used as unidimensional tools. Our study expands upon existing psychometric findings related to PHQ-9 and EPDS, offering valuable insights for their application in research and clinical settings.

A Follow up on the Continuum Theory of Eco-Anxiety: Analysis of the Climate Change Anxiety Scale Using Item Response Theory among French Speaking Population.

The mental health impact of the environmental crisis, particularly eco-anxiety, is a growing research topic whose measurement still lacks consensus. This study aims to use item response theory (IRT) to gain a deeper understanding of the constructs measured by existing questionnaires. To conduct this review, we applied the graded response model with the help of the MIRT package in R on open-access data from the short French version of the Climate Change Anxiety Questionnaire, which measures cognitive-emotional impairment and functional impairment. The models tested in this study are the one, two, and three-factor models, and the bifactor model. After model selection, the psychometric properties of the selected model were tested. Our results suggest that the unidimensional model seems to be the most appropriate for measuring eco-anxiety. The item difficulty parameter extracted from the IRT enabled us to discuss the severity levels of the items comprising this tool. The Climate Change Anxiety Questionnaire appears to be more appropriate for measuring moderate to severe eco-anxiety. Avenues for improving this questionnaire and the measurement of eco-anxiety in general are then discussed.

The Development and Initial Validation of the Multidimensional Fairness Scale

Research in psychology, sociology, economics, and other disciplines investigating social justice has identified associations between fair treatment and human well-being. However, the lack of a practical and valid instrument for measuring individual experiences of fair treatment in multiple areas of life has limited the ability to understand the relationship between fairness and wellness. The purpose of these studies was to develop and establish the initial psychometric properties and convergent validity of a scale measuring personal experiences of fairness across various life domains. Development and validation occurred across three studies. Scale development in Study 1 included the generation of items, item revision, and analysis of content validity. A review of existing literature and qualitative data derived from focus group discussions informed the initial pool of items. Cognitive interviews and expert input aided in analysis of content validity and revision of items. Study 2 consisted of confirmatory factor analyses to evaluate the performance of items and determine the underlying factor structure of the scale. In Study 3, factor analyses were used to evaluate convergent validity with other fairness-related instruments. Results of the first study supported the conceptualization of fairness along a social-ecological spectrum: experiences of fairness existed in multiple distinct life domains (e.g., interpersonal, occupational, community). Results from the second study revealed a bifactor model with one general Fairness factor and four Interpersonal, Occupational, Community, and Societal ecological group factors. Results from the third study suggested acceptable convergent validity among some subscales and other established instruments, while also suggesting that refinements to the Community fairness subscale might improve the scale. The final 12-item scale demonstrated good reliability. Results of this study produced an instrument able to measure individual experiences of fair treatment across four life domains.

Examining the role of personality functioning in a hierarchical taxonomy of psychopathology using two years of ambulatory assessed data

The Hierarchical Taxonomy of Psychopathology (HiTOP) arranges phenotypes of mental disorders based on empirical covariation, ranging from narrowly defined symptoms to higher-order spectra of psychopathology. Since the introduction of personality functioning (PF) in DSM-5 and ICD-11, several studies have identified PF as a predictor of transdiagnostic aspects of psychopathology. However, the role of PF in the HiTOP classification system has not been systematically examined. This study investigates how PF can be integrated into HiTOP, whether PF accounts for transdiagnostic variance captured in higher-order spectra, and how its predictive value for future affective well-being (AWB) and psychosocial impairment (PSI) compares to the predictive value of specific psychopathology beyond PF. To this end, we examined two years of ambulatory assessed data on psychopathology, PF, PSI, and AWB of N = 27,173 users of a mental health app. Results of bass-ackwards analyses largely aligned with the current HiTOP working model. Using bifactor modeling, aspects of PF were identified to capture most of the internalizing, thought disorder, and externalizing higher-order factor variance. In longitudinal prediction analyses employing bifactor-(S-1) modeling, PF explained 58.6% and 30.6% of variance in PSI and AWB when assessed across one year, respectively, and 33.1% and 23.2% of variance when assessed across two years. Results indicate that personality functioning may largely account for transdiagnostic variance captured in the higher-order components in HiTOP as well as longitudinal outcomes of PSI and AWB. Clinicians and their patients may benefit from assessing PF aspects such as identity problems or internal relationship models in a broad range of mental disorders. Further, incorporating measures of PF may advance research in biological psychiatry by providing empirically sound phenotypes.

Dimensions of parenting during infancy: Testing a latent bifactor model

AbstractIn the current paper, we examined the dimensional structure of parenting using a bifactor model of observed parenting domains during infancy. We validated our parenting dimensions by examining correlations with indicators of family well‐being and child development. Data come from a longitudinal cohort that recruited a diverse sample of mothers (56.5% White) and their newborn child (50.7% males). Parenting was assessed using multiple indicators at an average of 18 months (N = 397). Bifactor modelling revealed a general latent dimension of sensitivity and two unique dimensions indexing emotional input and cognitive input. We found a pattern of shared and unique correlations of the three parenting dimensions with family and child well‐being. The most robust correlations were with the general sensitivity dimension, which we argue cuts across parentings behaviors and is fundamental to development.

U.S. Secondary Students’ Source-Based Argument Writing in History

Developing students’ source-based argument writing skills is a vital educational goal for the 21st-century information society. Consequently, researchers and educators continually seek ways to understand and improve students’ capacities for advancing arguments and synthesizing multiple documents, texts, or sources in a range of subject areas in secondary schools. This study examined differences between middle and high school students’ argument essays (N = 207) in multiple dimensions of source-based argument writing in history, the dimensions writing in history, and the relations of identified dimensions to overall writing quality. Using multivariate analysis of covariance, middle and high school students’ writing significantly varied in areas of writing related to language use, the presentation of ideas, and evidence use. Their writing varied less so for skills related to historical thinking, indicating a lack of development in these skills across secondary school. Findings from confirmatory factor analysis and structural equation modeling showed a bifactor model with a general factor and 4 specific factors—Presentation of Ideas, Evidence Use, Language Use, and Historical Thinking—best represented writing in this genre, with the general factor strongly predicting holistic writing scores. Implications for both research and educational practice are discussed, including the importance of attending to developmental variation in discrete writing skills.

Translation and Validation of the Brazilian Version of the European Obesity Academy Questionnaire on Patients' Motivations for Seeking Metabolic and Bariatric Surgery.

Understanding patients' motives for undergoing metabolic and bariatric surgery (MBS) is key to managing postoperative expectations. We aimed to translate and validate the 14-item European Obesity Academy Questionnaire on Expectations about Surgical Treatment (EOAQ-EST) to Brazilian Portuguese for research and clinical use. This study included a total of 198 candidates for MBS at a reference academic hospital in Brazil from January 2021 to February 2022. We followed Beaton and Bombardier's guidelines for translation and cultural adaptation, including translation, back-translation, comparative analysis, expert review, pilot testing, and the creation of the final version of the questionnaire. Reliability was tested with McDonald's omega, and internal validity was assessed using confirmatory factor analysis (CFA). The final version was applied to 161 patients, 85% female, with a mean age of 46.4 ± 10.3years and a mean BMI of 48.3 ± 8.2kg/m2. Validity was supported by a bifactorial model (95% CI 0.044-0.104, p = 0.08), excluding one item (improved fertility) due to a floor effect. The reliability analysis showed that the 13 remaining items were internally consistent, with a McDonald's ω of 0.625. The Brazilian-Portuguese version of EOAQ-EST proved to be user-friendly, consistent, and reliable. This questionnaire may assist multidisciplinary teams in effectively addressing patients' expectations concerning metabolic and bariatric surgery (MBS) outcomes.

Beliefs about emotion usefulness are nuanced: degree of personal reference and emotional valence predict affective distress

ABSTRACT The beliefs people hold about emotions are implicated in a variety of outcomes including emotion regulation success and overall well-being. However, research on the dimensions of such beliefs is limited, typically addressing broad beliefs about all emotions and focusing only on their controllability. This study investigated emotion usefulness beliefs, specifically, and further parsed dimensions of personal reference (general vs. personal emotions) and valence (positive vs. negative). Study 1 (N = 343), applying a 2 × 2 factorial ANOVA, revealed that participants believed negative emotions in general to be more useful than their own negative emotions, with no such difference emerging for positive emotions. Multiple regression analyses indicated that personal beliefs about emotions better predicted affective distress than general beliefs. Study 2 (N = 531) replicated these findings and employed confirmatory factor analyses to psychometrically assess the distinctiveness of these emotion belief dimensions. Evaluating a two-factor model, four-factor model, and three-factor bifactor model, results showed that both the four-factor and bifactor models fit the data well, whereas the two-factor model did not. These findings suggest that beliefs about emotion in general and beliefs about one’s own emotions may not be fundamentally distinct, but rather different dimensions of the same underlying emotion usefulness belief.