Mokken Scale Analysis Research Articles

Mokken scale analysis of the Internet Gaming Disorder Scale–Short-Form and the Gaming Disorder Test

In recent years, research on Gaming Disorder (GD) has grown substantially with researchers developing different psychometric tools for assessing disordered gaming. Two of the most prominent tools are the Internet Gaming Disorder Scale–Short-Form (IGDS9-SF) and the Gaming Disorder Test (GDT), which assess disordered gaming under the American Psychiatric Association (APA) and the World Health Organisation (WHO) frameworks respectively. The main aim of this study was to assess and compare the scalability, reliability, and validity of both scales to determine if the tools effectively assess GD in a normative sample, through the Mokken Scale Analysis (MSA). A sample of 605 participants (42.31 % female, meanage = 23.98 years, SD = 9.21 years) was recruited for the present study. Results showed that both the IGDS9-SF and GDT were unidimensional, with all items presenting latent monotonicity fitting in the Monotone Homogeneity Model (MHM). Item characteristic curves did not intersect and presented with adequate fit in the Double Monotonicity Model (DMM). These findings further support the psychometric adequacy of the IGDS9-SF and GDT, attesting to their suitability to assess disordered gaming.

Examining the psychometric properties of the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 among young urban South African women

BackgroundValid, reliable, and easy-to-administer scales are crucial for identifying mental health conditions, especially in LMICs where such scales tend not to be validated. This study aims to address this gap by investigating the psychometric properties and factorial structure of the PHQ-9 and GAD-7 in a sample of young women in Soweto, South Africa. MethodsThe PHQ-9 and GAD-7 were administered to 6028 women aged 18–28 years old. Cronbach's alpha, Mokken scale analysis, and Confirmatory Factor Analysis were used to provide support for the internal consistency and construct validity of these scales. ResultsBoth scales demonstrated good internal consistency (α = 0.81 for PHQ-9 and α = 0.84 for GAD-7). Internal consistency reliability was further supported by positive inter-item correlations and item-by-scale correlations for all items on both measures. CFA of the PHQ-9 and GAD-7 showed a reasonable fit for the 1-factor model and 2-factor models (depression and anxiety with somatic and cognitive subtypes). LimitationsThis study was limited to young African women in urban Soweto who were proficient in English, which may affect generalizability. Differences in language or cultural context may impact the accuracy and applicability of these scales to other African populations. ConclusionThe PHQ-9 and GAD-7 are valid and reliable for identifying psychological distress in the studied population. Despite showing good psychometric properties, further diagnostic assessment is needed to confirm clinical diagnoses. The scales are useful for identifying those at risk but not a substitute for comprehensive diagnostic evaluations.

Measuring psychache as a suicide risk variable: A Mokken analysis of the Holden's Psychache Scale

BackgroundThe Psychache Scale (PAS) is a questionnaire measuring trait-level psychological pain with satisfactory internal consistency and a strong correlation with suicidal ideation severity. However, inconsistent results have been reported for the PAS dimensionality. In the present study we used a non-parametric item response theory model, called Mokken Scale Analysis (MSA), to refine an unidimensional version of the PAS. MethodsThe sample was composed of 400 Italian adults (312 females and 88 males) nonrandomly recruited from the general population. ResultsA final set of 10 items satisfied the unidimensionality, local independence, and monotonicity assumptions, although it did not satisfy the double monotonicity assumption. The internal consistency of the PAS-10 was satisfactory (ordinal alpha = 0.98, ω = 0.97, and AVE = 0.82), and ROC curves analysis indicated good discriminant validity when differentiating participants with higher suicide risk from those with lower suicide risk. LimitationsStructural invariance between nonclinical and clinical samples was not investigated, and the presence of suicide ideation and behaviors was assessed with self-report measures with potential under-reporting of the phenomenon. ConclusionThe PAS-10 resulted to be a potentially valid and unidimensional measure of psychological pain (i.e., psychache) that could be used to screen adults at higher risk for suicide. Future studies are needed to investigate psychometric properties of the PAS-10 in clinical samples and to replicate results in independent samples.

Addressing the role of eHealth literacy in shaping popular attitudes towards post-COVID-19 vaccination among Chinese adults

This study examined the influence of eHealth literacy on Chinese individuals’ attitudes towards post-COVID-19 vaccination and explored methods to address obstacles related to eHealth literacy that could affect their comprehension and willingness to get vaccinated. In 2022, a web-based cross-sectional survey was conducted to assess the vaccination-related knowledge, attitudes and intentions of 950 participants. Vaccination knowledge was established by employing validated measures and conducting a Mokken scale analysis. Causal-directed acyclic graphs were used to illustrate the current comprehension of the correlation between eHealth literacy and the desire to receive vaccinations. This study utilised causal mediation and multiple linear regression analysis to determine the relationships between eHealth literacy, vaccination knowledge, vaccination willingness and subjective health status. The primary finding of this study was that an individual’s comprehension of vaccination was a robust indicator of their inclination to receive vaccination. Moreover, eHealth literacy has an indirect effect on the propensity to get vaccinated by enhancing one’s understanding of vaccines. This study emphasises the significant role of eHealth literacy in enhancing vaccination awareness and willingness, particularly among Chinese adults with poorer health in the post-COVID-19 period. The results affirm the efficacy of employing eHealth technologies to bolster immunisation initiatives, amplify vaccine consciousness, and promote compliance. Moreover, this study emphasises the significance of additional research to assess and record the function of eHealth literacy in immunisation practices.

Item Hierarchy of Vocal Fatigue Index (VFI) in School Teachers—A Study from South India

AimThe study aimed to identify the item hierarchy of the Vocal Fatigue Index (VFI) in school teachers using Mokken Scaling Analysis (MSA). MethodA total of 362 school teachers from five zones in Chennai city, southern part of India, participated in the study. All subjects completed a subject information form that had details such as age, sex, duration of vocal demand per day, number of classes taken, grades taught, and years of experience and VFI. Based on the VFI factor I scores, teachers were segregated into three groups, viz., No fatigue (NF; <11), Low Fatigue (LF; 11-24), High Fatigue (HF; >24). Percentage analysis, Mann Whitney U, Pearson’s chi square was done for finding the association of variables (listed above) with vocal fatigue and MSA. ResultsTwo-hundred and seventy-five teachers (75.5%) identified themselves with vocal fatigue, and 87 (24%) others reported no vocal fatigue. The highest percentage of fatigue (63.18%) was documented in factor II, followed by factor III (48.90%), and factor I (40.38%). Mann Whitney U test revealed a significant difference in vocal fatigue experience between males and females (p=0.01). Pearson chi square showed a positive association between factor I and years of experience in teachers (p=0.02). No significant correlation was observed between other variables and factors of VFI. MSA divided the VFI scale into two, scale 1 (factor I & II) and scale 2 (factor III). On segregation, several reliable scales were obtained, however, all the scales had a low Loevinger’s coefficient. Discussion/ConclusionVFI, though a reliable tool, did not capture the underlying trait of vocal fatigue completely in school teachers as a population. This study ascertains the need to develop a tool that is specific to occupation/profession, geographic, socio-cultural, and ethnic group. Mere adaptations and translations of tools may not necessarily suffice for clinical utility and application.

Total, Between-, and Within-Item Attribute Person Fit Analysis Using Mokken Scaling Techniques: An Exploratory Nonparametric Approach to Person Fit

The purpose of this study was to consider how researchers can incorporate item attributes into nonparametric person fit analysis for the purpose of providing additional insight into person fit beyond what is available using typical total-scale person fit approaches. Inspired by parametric person fit statistics that consider patterns of residuals at the total-scale, between-item-attribute, and within-item-attribute levels, we proposed simple adaptations to standard Mokken Scale Analysis (MSA) person fit analysis techniques to reflect these three levels of person fit analysis. We demonstrated the technique using a secondary analysis of survey data related to learning motivation and considered how the results may be interpreted in an affective assessment context. We used a simple exploratory simulation study to consider the techniques under a wider range of conditions. Overall, the results suggested that it is possible to incorporate item attributes into MSA person fit analysis at the total-scale, between-item-attribute, and within-item attribute levels, and that each set of analyses provides a unique perspective on person fit.

Harmonizing perspectives to understand attitudes: A mixed methods approach to crafting an assessment literacy attitude scale

Assessment literacy's vital role in faculty effectiveness within higher education lacks sufficient tools for measuring faculty attitudes on this matter. Employing a sequential mixed-methods approach, this study utilized the theory of planned behavior to develop the Assessment Literacy Attitude Scale (ALAS) and evaluate its psychometric properties within the U.S. higher education context. The qualitative phase involved a literature review of relevant studies and existing self-report measures, interviews with stakeholders, and panel reviews to shape initial item development. Following the establishment of a conceptual foundation and a comprehensive overview of the scale's construction, our study advanced to the quantitative stage that involves factor analytical and item response theory approaches using data from 260 faculty across three public universities in the U.S. Exploratory factor analysis (EFA) was employed initially to obtain preliminary insights into the scale's factorial structure and dimensionality. Confirmatory factor analysis (CFA) was subsequently applied with separate data and the findings largely supported the conclusions from the EFA. Exploratory and confirmatory factor analyses resulted in 15 items loading across two factors in a good model fit range. Finally, we used nonparametric item response theory (IRT) techniques based on Mokken Scale Analysis (MSA) to evaluate individual items for evidence of effective psychometric properties to support the interpretation of ALAS scores, including monotonicity, scalability, and invariant item ordering. The newly-developed scale shows promise in assessing faculty attitudes toward enhancing their assessment literacy.

Improved Accuracy of the Addenbrooke's Cognitive Examination-Revised in the Diagnosis of Mild Cognitive Impairment, Mild Dementia Due to Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia Using Mokken Scale Analysis.

The Addenbrooke's Cognitive Examination-Revised (ACE-R) is an accessible cognitive tool that supports the early detection of mild cognitive impairment (MCI), Alzheimer's disease (AD), and behavioral variant frontotemporal dementia (bvFTD). To investigate the diagnostic efficacy of the ACE-R in MCI, AD, and bvFTD through the identification of novel coefficients for differentiation between these diseases. We assessed 387 individuals: 102 mild AD, 37 mild bvFTD, 87 with amnestic MCI patients, and 161 cognitively unimpaired controls. The Mokken scaling technique facilitated the extraction out of the 26 ACE-R items that exhibited a common latent trait, thereby generating the Mokken scales for the AD group and the MCI group. Subsequently, we performed logistic regression, integrating each Mokken scales with sociodemographic factors, to differentiate between AD and bvFTD, as well as between AD or MCI and control groups. Ultimately, the Receiver Operating Characteristic curve analysis was employed to assess the efficacy of the coefficient's discrimination. The AD-specific Mokken scale (AD-MokACE-R) versus bvFTD exhibited an Area Under the Curve (AUC) of 0.922 (88% sensitivity and specificity). The AD-MokACE-R versus controls achieved an AUC of 0.968 (93% sensitivity, 94% specificity). The MCI-specific scale (MCI-MokACE-R) versus controls demonstrated an AUC of 0.859 (78% sensitivity, 79% specificity). The ACE-R's capacity is enhanced through statistical methods and demographic integration, allowing for accurate differentiation between AD and bvFTD, as well as between MCI and controls. This new method not only reinforces its clinical value in early diagnosis but also surpasses traditional approaches noted in prior studies.

The MACE-SCREEN – Screening for Abuse and Neglect Across Developmental Stages

ABSTRACT Few high-quality instruments are available to comprehensively screen for multiple interpersonal traumatic childhood experiences differentiated by developmental stage. One instrument assessing various forms of childhood trauma is the Maltreatment and Abuse Chronology of Exposure (MACE-X, Teicher & Parigger, 2015), which allows for the assessment of age at exposure for every item. The aim of this study is the development of a shorter version, which is suitable for screening. In- and out-patients (n = 719) of a somatic clinic were assessed with the German version of the 75-item MACE. Descriptive statistics, a nonparametric item response theory model (Mokken Scale Analysis), and factor analysis were combined to select items for a screening version. A screener (MACE-SCREEN) with 39 items allocated to five scales was developed. Scales differentiate between abuse types and neglect, direct experience vs. witnessing violence, and the age of the perpetrator (adults vs. peers). The scales showed good internal consistency (Alpha .78 to .91) and the total score a strong correlation with the total score of the long version (r = .96). This screening version is still comprehensive as it assesses exposure to various forms of interpersonal traumatic events, including peer violence and witnessing domestic abuse. As it also allows for the concurrent assessment of age at exposure, it lends itself to assessing exposure across developmental stages.

Development of the Brazilian version of the Mini-Addenbrooke Cognitive Examination (M-ACE BR) to screen for cognitive impairment in older adults.

Age is the most important risk factor for develop dementia, and the recommendation is that older adults are cognitively tested to detect impairment in the initial stage for adequate treatment. The demand for the care of these older adults is great, drawing attention to the need for rapid tests, with good accuracy and simple application to identify cognitive impairment. To develop and validate the Brazilian Mini-Addenbrooke Cognitive Examination (M-ACE BR) as a short screening test for cognitive impairment in older adults. The M-ACE BR was developed using the Mokken scaling analysis in 352 participants (cognitively unimpaired [CU] = 232, cognitive impairment no dementia [CIND] = 82; and dementia = 38) and validated in an independent sample of 117 participants (CU = 25; CIND = 88; and dementia = 4). The Mokken scaling analysis derived 9 items (spatial orientation, anterograde memory, retrograde memory, delayed recall, recognition [name and address], letter verbal fluency, repetition of 4 words, naming of 10 items, and comprehension) with a maximum score of 51 points and an average duration time of 7 minutes. The cut-off score ≤ 43/51 for CIND had a sensitivity of 59.09% and a specificity of 80%. For a screening test in which sensitivity is prioritized for further investigation, we suggest using a cutoff of ≤ 47 (sensitivity 85.23% and specificity 24%), maintaining a good positive predictive value (79.8%). The M-ACE BR is a brief and adequate instrument to detect cognitive impairment in older Brazilian adults. However, screening for CIND and for different educational levels should be further explored.

Combining Mokken Scale Analysis with Rasch measurement theory to explore differences in measurement quality between subgroups

Mokken Scale Analysis (MSA) is a nonparametric approach that offers exploratory tools for understanding the nature of item responses while emphasizing invariance requirements. MSA is often discussed as it relates to Rasch measurement theory, which also emphasizes invariance, but uses parametric models. Researchers who have compared and combined MSA and Rasch approaches have generally concluded that these approaches offer complementary perspectives. However, researchers have not considered how the two approaches may provide insight related to examinee subgroups. Using a simulation and illustrative real data analysis, we propose an exploratory approach to integrating MSA and Rasch techniques to understand item fit as it relates to differences in item characteristics between examinee subgroups. Our results suggest that integrating complete-sample and subgroup-level MSA and Rasch model item fit analyses can provide insight into differences in item quality between subgroups. In some cases, misfit at the complete sample level corresponds to subgroup-related differences. On the other hand, fit at the complete sample level does not guarantee consistent measurement properties within subgroups. When subgroups are important for scale interpretation and use, our results suggest that conducting separate analyses within groups and considering their results with respect to those from the full sample may lend useful insight.

Using a nonparametric item response theory model to identify patterns of cognitive decline: The Mokken scale analysis.

Cognitive decline, particularly in dementia, presents complex challenges in early detection and diagnosis. While Item Response Theory (IRT) has been instrumental in identifying patterns of cognitive impairment through psychometric tests, its parametric models often require large sample sizes and strict assumptions. This creates a need for more adaptable, less demanding analytical methods. This study aimed to evaluate the effectiveness of Mokken scale analysis (MSA), a nonparametric IRT model, in identifying hierarchical patterns of cognitive impairment from psychometric tests. Using data from 1164 adults over 60 years old, we applied MSA to the orientation subscale of ACE-III. Our analysis involved calculating scalability, monotone homogeneity, invariant item ordering (IIO) and response functions. The MSA effectively retrieved the hierarchical order of cognitive impairment patterns. Most items showed strong scalability and consistent patterns of cognitive performance. However, challenges with IIO were observed, particularly with items having adjacent difficulty parameters. The findings highlight MSA's potential as a practical alternative to parametric IRT models in cognitive impairment research. Its ability to provide valuable insights into patterns of cognitive deterioration, coupled with less stringent requirements, makes it a useful tool for clinicians and researchers.

Validation of an improved questionnaire assessing the social cognitive constructs of the Health Action Process Approach among parents regarding brushing their children's teeth.

The Health Action Process Approach (HAPA) describes social cognitive constructs related to behaviour change. A validated questionnaire is needed to measure these constructs in paediatric dentistry. The aim of this study was to improve an existing HAPA-based questionnaire for parents regarding brushing their children's teeth and to assess its validity and reliability in a population of parents of high caries risk children. Parents of high caries risk children of 3-10 years filled out the adjusted HAPA-based questionnaire. Mokken scale analysis, graded response model analyses, factor analyses and reliability analyses were performed according to the protocol of Dima. Discriminant validity was assessed by comparing the mean scores of the HAPA constructs between two groups of participants, based on different levels of caries experience, brushing frequency and education level of the mother. The Mokken scale analysis and factor analyses indicated a multidimensional eight factor scale. The graded response model did not fit our data. The subscale action control could be identified as a two-factor subscale. Reliability indices from the Dima protocol varied, for instance Cronbach alpha ranged from 0.73 to 0.96. The constructs coping self-efficacy, action planning and action control discriminated between brushing frequencies. The adjusted HAPA-based questionnaire is an improved, valid and reliable instrument that could be used to evaluate HAPA-based interventions to improve children's oral health.

Validation of the de Morton mobility index (DEMMI) among acute stroke patients aged ≥65 years: a register study

Purpose To validate the de Morton Mobility Index (DEMMI) in older (≥65 years) patients with acute stroke in a hospital setting within the first week after stroke onset. Materials and methods In the Danish National Database of Geriatrics, we identified 4,176 patients with acute stroke (≥65 years). Floor and ceiling effects of DEMMI were investigated. Furthermore, convergent validity was investigated by correlations between DEMMI and the Barthel Index using Spearman’s rho. Known-groups validity was tested by comparing DEMMI scores for different groups (with/without dementia, depression, comorbidity, and walking aids), and unidimensionality of DEMMI was evaluated by Mokken scale analysis. Results A floor effect was identified with 22.1% of the patients scoring 0 on DEMMI on admission. Both convergent and known-groups validity were confirmed for DEMMI. Patients who were bedbound had a lower DEMMI score (median [IQR]: 0 [0;0]) than patients without any walking aid (median [IQR]: 62 [33;74]). Furthermore, Mokken scale analysis identified unidimensionality with overall fit to the model (Loevinger H 0.88 (p < 0.0001)). Conclusion DEMMI is a valid instrument for use in patients with acute stroke (≥65 years) in a hospital setting within the first week after stroke onset.

Measurement of perceived pressures in psychiatry: paper-and-pencil and computerized adaptive version of the P-PSY35 scale

PurposeFormal coercion in psychiatry is widely studied yet much less is known about pressures patients may experience, partly because of the very few measures available. The goal of this study was to validate the P-PSY35 (Pressures in Psychiatry Scale) and provide a paper-and-pencil and a computerised adaptive test (CAT) to measure pressures experienced by patients in psychiatry.MethodsThe P-PSY35 items were developed with users. Patients were evaluated during psychiatric hospitalisation or through an online survey. Mokken scale analysis and Item response theory (IRT) were used to select and estimate the items parameters. A Monte-Carlo simulation was performed to evaluate the number of items needed to transform the paper-and-pencil test into a reliable psychometric CAT.ResultsA total of 274 patients were assessed. The P-PSY35 demonstrated good internal validity, internal consistency, convergent and divergent validity. The P-PSY35 could be substantially shortened while maintaining excellent reliability using the CAT procedure.ConclusionThe P-PSY35 was developed in collaboration with users. It is a psychometrically rigorous tool designed to measure experienced pressures in French-language. The development and successful validation of the P-PSY35 represent a welcome step towards implementing and evaluating programs aimed at reducing negative consequences of coercion.

EFL Teachers’ Attitudes towards Mobile Teaching Affordances: A Mokken Scale Analysis

In contemporary education settings, the expeditious advancement of mobile devices, wireless communications and network infrastructures has emerged as a crucial issue. Although mobile technology capabilities and affordances have attracted considerable attention, there is a lack of a valid scale for evaluating mobile teaching affordances. Therefore, this research sought to develop and validate a 36-item inventory of mobile teaching affordances. To accomplish this objective, 204 EFL teachers in this research utilising the convenience sampling method. The data was analysed using the Mokken scale analysis. The study results indicated that 10 out of 36 items should be deleted to optimise the utilisation of the data. Consequently, the study created a valid and reliable 26-item inventory that could be used to measure mobile teaching affordance in EFL or ESL teaching contexts. The research findings suggested that the newly created scale is an invaluable instrument for evaluating the perspectives of EFL teachers regarding the potential benefits of mobile teaching. Furthermore, it can effectively pinpoint areas where teachers may require further development in their understanding of and proficiency in utilising mobile teaching methods. These revelations can also act as a basis for developing instructional programmes aimed at empowering EFL teachers to seamlessly incorporate mobile devices into their pedagogical approaches, thereby enhancing their overall effectiveness. The study’s findings can be used by teachers, learners and researchers in educational systems.

Combining Nonparametric and Parametric Item Response Theory to Explore Data Quality: Illustrations and a Simulation Study

ABSTRACT Researchers who use measurement models for evaluation purposes often select models with stringent requirements, such as Rasch models, which are parametric. Mokken Scale Analysis (MSA) offers a theory-driven nonparametric modeling approach that may be more appropriate for some measurement applications. Researchers have discussed using MSA as a preliminary procedure with which to evaluate data quality before applying a parametric model. However, the literature includes only a few examples in which researchers have integrated MSA techniques with parametric models throughout the analytic procedure. We consider a systematic approach for integrating results from nonparametric MSA techniques with parametric measurement models to evaluate measurement quality and construct scales with useful measurement properties. We use real-data illustrations and a simulation study to demonstrate and systematically explore our approach. We discuss implications for research and practice.

Construction and Normalization of Competency Evaluative Indicators based on the Screening of Psychological and Personality Fundamental Scales with the Third Edition of Minnesota Multiphasic Personality Inventory (MMPI-3)

This research aimed to construct, validate and normalize a measuring scale of competency evaluative indicators based on the screening of psychological and personality fundamental scales with the Third Edition of Minnesota Multiphasic Personality Inventory (MMPI-3). Present study aimed that competency indicators can be measured with a validate instrument named MMPI-3. We assessed the validity of this new measure applied to 3000 participating from Iran. We obtained evidence for (a) content validity (through item analysis), (b) internal structure with Mokken Scaling Analysis and structural equation modeling to examine the item–construct relationship, differential item functioning, and reliability, and (c) association with external variables. The items were found to function one-dimensionally, with strong item–construct relationships and no differential functioning. Theoretically consistent associations were found between scales of MMPI-3 and constructed Indicators by researchers. The findings of the present study shown that (a) we can assess competency indicators as second layer of MMPI-3 profile, (b) there’s a strong correlation among competency indicators and MMPI-3 scales as reverse layer and (c) constructed indicators by researchers are validate and reliable to assess competency indicators for evaluating and screening psychological and personality features

A Place to Feel at Home? An Exploratory Study of the Perceived Living Environment in Home-Like Groups, Family-Style Group Homes, and Traditional Residential Youth Care

ABSTRACT Traditionally, residential youth care (RYC) in the Netherlands has been characterized by short-term placements, groups with relatively large numbers of youth (8–12), often located on a campus with several RYC units. Recently, alternative RYC settings have been developed to create a home-like environment and promote stability. These alternative settings are characterized by long-term care, smaller groups (typically 6), and placements within the community. Examples of alternative RYC settings are home-like groups and family-style group homes (with live-in professionals). We aimed to gain insight into the perceived living environment in different RYC settings from the perspectives of 26 youth, 14 parents, and 35 professionals. Quantitative data were collected using q-methodology. To deal with the small sample size, we used a triangulation of techniques: the Mokken scale, Mann-Whitney, and by-person factor analyses to explore differences in perceived living environments between RYC settings. We found that participants in home-like groups experienced significantly more sensitivity from professionals than did participants in traditional RYC. Participants in alternative RYC tended to emphasize sensitivity, while participants in traditional RYC tended to emphasize factual conditions. Alternative RYC may provide more opportunities than traditional RYC for youth to experience an environment with sensitive professionals and a positive group atmosphere.

C-Test construct validity: Evidence from nonparametric item response theory

C-Test is a gap-filling test designed to measure first and second language proficiency. Over the past four decades, researchers have shown the fit of C-Test data to parametric item response theory (IRT) models, but no study so far has shown the fit of C-Tests to nonparametric IRT models. The purpose of this study is to contribute to the ongoing C-Test validation project by providing evidence of fit to the Mokken scale analysis as a widely used nonparametric IRT model. A six-passage C-Test battery was analyzed using the monotone homogeneity model and the double monotonicity model of Mokken. Unidimensionality was evaluated using the automatic item selection procedure. Findings showed that the C-Test passages form a strong unidimensional scale, fit well to the monotone homogeneity model, and, after deleting one item, have a sufficient fit to the double monotonicity model. The findings also indicated that the items form a hierarchy, and persons can be located on an ordinal scale using their C-Test sum scores. Implications of the study for C-Test validity and application are discussed.