Item Infit Research Articles

Designing and Testing an Inventory for Measuring Social Media Competency of Certified Health Education Specialists.

BackgroundSocial media can promote healthy behaviors by facilitating engagement and collaboration among health professionals and the public. Thus, social media is quickly becoming a vital tool for health promotion. While guidelines and trainings exist for public health professionals, there are currently no standardized measures to assess individual social media competency among Certified Health Education Specialists (CHES) and Master Certified Health Education Specialists (MCHES).ObjectiveThe aim of this study was to design, develop, and test the Social Media Competency Inventory (SMCI) for CHES and MCHES.MethodsThe SMCI was designed in three sequential phases: (1) Conceptualization and Domain Specifications, (2) Item Development, and (3) Inventory Testing and Finalization. Phase 1 consisted of a literature review, concept operationalization, and expert reviews. Phase 2 involved an expert panel (n=4) review, think-aloud sessions with a small representative sample of CHES/MCHES (n=10), a pilot test (n=36), and classical test theory analyses to develop the initial version of the SMCI. Phase 3 included a field test of the SMCI with a random sample of CHES and MCHES (n=353), factor and Rasch analyses, and development of SMCI administration and interpretation guidelines.ResultsSix constructs adapted from the unified theory of acceptance and use of technology and the integrated behavioral model were identified for assessing social media competency: (1) Social Media Self-Efficacy, (2) Social Media Experience, (3) Effort Expectancy, (4) Performance Expectancy, (5) Facilitating Conditions, and (6) Social Influence. The initial item pool included 148 items. After the pilot test, 16 items were removed or revised because of low item discrimination (r<.30), high interitem correlations (Ρ>.90), or based on feedback received from pilot participants. During the psychometric analysis of the field test data, 52 items were removed due to low discrimination, evidence of content redundancy, low R-squared value, or poor item infit or outfit. Psychometric analyses of the data revealed acceptable reliability evidence for the following scales: Social Media Self-Efficacy (alpha=.98, item reliability=.98, item separation=6.76), Social Media Experience (alpha=.98, item reliability=.98, item separation=6.24), Effort Expectancy(alpha =.74, item reliability=.95, item separation=4.15), Performance Expectancy (alpha =.81, item reliability=.99, item separation=10.09), Facilitating Conditions (alpha =.66, item reliability=.99, item separation=16.04), and Social Influence (alpha =.66, item reliability=.93, item separation=3.77). There was some evidence of local dependence among the scales, with several observed residual correlations above |.20|.ConclusionsThrough the multistage instrument-development process, sufficient reliability and validity evidence was collected in support of the purpose and intended use of the SMCI. The SMCI can be used to assess the readiness of health education specialists to effectively use social media for health promotion research and practice. Future research should explore associations across constructs within the SMCI and evaluate the ability of SMCI scores to predict social media use and performance among CHES and MCHES.

Screening for depression in pregnant women from Côte d׳Ivoire and Ghana: Psychometric properties of the Patient Health Questionnaire-9

BackgroundMajor depression in antepartum women is a considerable health problem. This article aims at exploring the psychometric properties of the 9-item Patient Health Questionnaire (PHQ-9) in West African pregnant women. MethodsIn a cross-sectional survey, the PHQ-9 was administered to n=639 Ivorian and n=389 Ghanaian women in their last trimester of pregnancy (gestational age range: 28–40 weeks) in 2010–11. Statistical analysis applied methods from both classical test theory (CTT) and item response theory (IRT). ResultsInternal consistency was Cronbach׳s α=.65 in Côte d׳Ivoire and α=.68 in Ghana. Investigation of factorial validity by confirmatory factor analyses showed that unidimensionality of the PHQ-9 was sufficient. Rasch analyses resulted in excellent item infit and outfit measures. Yet, unidimensionality was questionable in residual principal component analyses. IRT analyses suggested that the response categories were not utilized as intended. Analysis of differential item functioning revealed interviewer-related item bias for several items in both samples. Item-person-fit was not ideal because the PHQ-9 items showed a low discriminability in the region of the latent trait where the majority of the women from the general population were located. Convergent validity was demonstrated by correlations between the PHQ-9 and two measures assessing anxiety and perceived disability. LimitationsBoth samples were quite homogenous regarding residence in urban areas and gestational age. ConclusionsIn our samples of African pregnant women, depression measured with the PHQ-9 does not appear as an entirely homogenous construct. However, the use of the sum score of the PHQ-9 is appropriate for depression screening purposes.

Psychometric properties of the 7-item Generalized Anxiety Disorder scale in antepartum women from Ghana and Côte d’Ivoire

BackgroundTo explore the psychometric properties of the 7-item Generalized Anxiety Disorder scale (GAD-7) in West African pregnant women. MethodsIn a cross-sectional study, the GAD-7, the PHQ-9 (depression module of the Patient Health Questionnaire) and the WHO-DAS II (12-item World Health Organization Disability Scale) were administered to n=647 Ivorian and n=395 Ghanaian antepartum women with low-risk pregnancies (third trimester; gestational age range: 28–40 weeks) in 2010–2011. Statistical analyses combined classical test theory (CTT) and item response theory (IRT). ResultsCronbach׳s α was close to acceptable (α=.69 in Côte d’Ivoire; α=.67 in Ghana). Construct validity was demonstrated by correlations between the GAD-7 and both the PHQ-9 and the WHO-DAS II. Results regarding factorial validity were ambiguous: confirmatory and exploratory factor analyses indicated that the data fit the unidimensionality assumption; however, the explained variance was low. IRT methods suggested excellent item infit and outfit measures. Yet, residual principal component analyses showed a lack of unidimensionality. Rasch analyses revealed that the response options were not used as intended. Item-person-fit was not optimal since the items did not discriminate well on the range of the latent construct where most of the women drawn from the general population were located. LimitationsBoth samples were somewhat homogenous regarding gestational age and urban residence; test–retest reliability was not investigated. ConclusionThe GAD-7 met the requirements of CTT. However, applying the stricter criteria of IRT suggested areas for potential improvements. Cross-cultural adaption and a dichotomized response format might ameliorate the GAD-7 for the use in sub-Saharan countries.

Development and validation of the 21‐item Children's Vision for Living Scale (CVLS) by Rasch analysis

BackgroundThe aim was to develop and validate an instrument called the ‘Children's Vision for Living Scale’ (CVLS) for the assessment of vision‐related quality of life in Saudi Arabian children with and without amblyopia.MethodsA 43‐item child self‐report questionnaire was initially developed based on interviews with children with amblyopia, their parents and eye‐care professionals, and a literature review. Following a process that involved the removal of redundant items, 28 items remained and were piloted on children aged five to 12 years with and without amblyopia (n = 48 amblyopic, n = 53 non‐amblyopic) living in Saudi Arabia. Rasch analysis was applied to determine whether the 28‐item questionnaire fitted the Rasch model. Rasch analysis was used to assess the validity and reliability of the questionnaire. Principal components analysis (PCA) was used to check dimensionality. A 21‐item questionnaire resulting from this process was administered in children with (n = 81) and without (n = 82) amblyopia in Saudi Arabia for further validation.ResultsThe final 21‐item questionnaire had good validity and reliability as demonstrated by person separation of 2.02, person reliability of 0.80 (mean square and standard deviation: infit = 1.01 ± 0.39; outfit = 1.01 ± 0.40) and item reliability of 0.93 (item infit range = 1.33 to 0.78; item outfit range = 0.78 to 1.30). The mean difference between person and item scores of 0.33 ± 0.53 logits (scale range, 2 to ‐2) indicates that the items are well targeted to the populations. The PCA (dimensionality measures) shows the percentage of variance explained by measures equal to 26.4 per cent (modelled 26.9 per cent) and an eigenvalue of the first contrast of 2.5, which demonstrated good stability.ConclusionThe 21‐item CVLS is a valid uni‐dimensional child self‐report instrument for the assessment of the impact of amblyopia on vision‐related quality of life in children with and without amblyopia living in Saudi Arabia.

Development of the Functional Vision Questionnaire for Children and Young People with Visual Impairment: The FVQ_CYP

To develop a novel age-appropriate measure of functional vision (FV) for self-reporting by visually impaired (VI) children and young people. Questionnaire development. A representative patient sample of VI children and young people aged 10 to 15 years, visual acuity of the logarithm of the minimum angle of resolution (logMAR) worse than 0.48, and a school-based (nonrandom) expert group sample of VI students aged 12 to 17 years. A total of 32 qualitative semistructured interviews supplemented by narrative feedback from 15 eligible VI children and young people were used to generate draft instrument items. Seventeen VI students were consulted individually on item relevance and comprehensibility, instrument instructions, format, and administration methods. The resulting draft instrument was piloted with 101 VI children and young people comprising a nationally representative sample, drawn from 21 hospitals in the United Kingdom. Initial item reduction was informed by presence of missing data and individual item response pattern. Exploratory factor analysis (FA) and parallel analysis (PA), and Rasch analysis (RA) were applied to test the instrument's psychometric properties. Psychometric indices and validity assessment of the Functional Vision Questionnaire for Children and Young People (FVQ_CYP). A total of 712 qualitative statements became a 56-item draft scale, capturing the level of difficulty in performing vision-dependent activities. After piloting, items were removed iteratively as follows: 11 for high percentage of missing data, 4 for skewness, and 1 for inadequate item infit and outfit values in RA, 3 having shown differential item functioning across age groups and 1 across gender in RA. The remaining 36 items showed item fit values within acceptable limits, good measurement precision and targeting, and ordered response categories. The reduced scale has a clear unidimensional structure, with all items having a high factor loading on the single factor in FA and PA. The summary scores correlated significantly with visual acuity. We have developed a novel, psychometrically robust self-report questionnaire for children and young people-the FVQ_CYP-that captures the functional impact of visual disability from their perspective. The 36-item, 4-point unidimensional scale has potential as a complementary adjunct to objective clinical assessments in routine pediatric ophthalmology practice and in research.

Cross-sectional validation of the Rasch-based Depression Screening (DESC) in a mixed sample of patients with mental and somatic diseases

BackgroundThe study aimed to cross-validate the psychometric properties of the two parallel versions of the “Rasch-based Depression Screening (DESC)” in a mixed clinical sample of patients with mental disorders and somatic diseases. Additionally, it was intended to confirm the initially proposed cut-off scores. MethodsOne hundred eleven inpatients from the Departments of Psychiatry (n=50), Cardiology (n=39) and Otorhinolaryngology (n=22) were examined. Accordance to Rasch model assumptions was determined by analyzing item infit and outfit as well as unidimensionality and local independence via residual principal components factor analysis (PCFA). Furthermore, separation, reliability and the targeting were considered. Differential item functioning (DIF) was investigated with regard to gender, age and clinical group. Finally, receiver operating characteristics (ROC) curves analyses were conducted and parallel test reliability was calculated. ResultsItem and person separation and reliability were good with separation values being above 2.90 and reliability exceeding being .90. Rasch model fit was good for all items except for the two items “sad” and “hopeless” displaying slight misfit. Targeting was appropriate with a person mean of −1.6 (DESC-I) and −1.5 (DESC-II) reflecting as expected that the two DESC versions were in average to easy for a mixed sample of patients with mental disorders and somatic. PCFA showed unidimensionality and local independence: The Rasch dimension “depression” explained 84.8% (DESC-I) and 82.2% (DESC-II) of the observed variance. No DIF was found. ROC curves confirmed the proposed cut-off score of 12 points. The area under the curve amounted to .91 for both DESC forms. The Youden index was 75.5 for DESC-I and 75.7 for DESC-II. A high parallel test reliability of .94 showed virtual equivalence of both DESC forms. ConclusionsResults of the present study support the good psychometric properties of both DESC forms in patients with mental disorders and somatic diseases. This study confirmed the cut-off scores that had already been determined in former patient samples. Thus, both DESC forms can be used validly as screening instruments for depression in clinical practice.

Development and Validation of the Dietary Sodium Reduction Self-Care Agency Scale

A scale did not exist for measuring the capability or self-care agency of lowering salt consumption in older adults with hypertension. Therefore, our objectives were to develop and validate the Dietary Sodium Reduction Self-Care Agency Scale (DSR-SCA Scale). A 24-item scale was developed and tested in 242 older adults with hypertension. Exploratory factor analysis using principal components extraction, Rasch analysis, and internal consistency reliability were used to evaluate the DSR-SCA Scale. Principal components extraction with Promax rotation was used. An 11-item DSR-SCA Scale with three factor loadings, which measure proficiency, persuasiveness, and resourcefulness, was finalized after it was found to meet the criteria of a minimal factor loading of 0.40, with eigenvalues of 2.20, 1.73, and 1.64, respectively. The Kaiser-Meyer-Olkin was 0.80, and Bartlett's test was significant, χ(2) (df = 55) 403.71, p < 0.0001. The measures accounted for 51% of the total variance. Item infit and outfit mean square ranged from 0.88 to 1.18 and the infit and outfit standardized mean square was -1.8 to 1.7. The 11-item scale demonstrated internal consistency with a Cronbach's alpha coefficient of 0.73 for the total scale. The results showed that the DSR-SCA Scale consisted of three factors that have adequate construct validity and reliability to measure power components and enabling capability related to Orem's self-care theory. This scale is brief, easy-to-complete, and useful for measuring salt reduction self-care agency in older adults with hypertension

Rasch Analysis of US Household Food Security Survey Module in Latino Migrant Farmworkers

This secondary analysis evaluated the validation of the short version of the US Department of Agriculture's Household Food Security Survey Module (HFSSM) in a Latino migrant population. The Rasch model assessed the HFSSM's structure, item severity levels, and fitness of the sample population. Differential item functioning (DIF) analysis explored the invariance of HFSSM response patterns between less/more acculturated households. Item infit scores were within an adequate range (0.7–1.3). Item severity scores and unidimensionality structure supported the HFSSM's theoretical framework. Analysis showed statistically nonsignificant DIF contrast between acculturation levels. The adapted HFSSM performed in agreement with the theoretical framework of food insecurity as a managed process in this Latino migrant population.

Rasch Analysis of the Ocular Surface Disease Index (OSDI)

The Ocular Surface Disease Index (OSDI) is a 12-item scale for the assessment of symptoms related to dry eye disease and their effect on vision. Its reliability and validity have been investigated within the classical test theory framework and, more recently, using Rasch analysis. The purpose of the present analysis was to more completely investigate the functioning of its response category structure, the validity of its three subscales, and the unidimensionality of the latent construct it is intended to assess. Responses to the OSDI from 172 females participating in the Dry Eye in Postmenopause (DEiM) study who had previously been diagnosed with dry eye or reported significant ocular irritation and dryness were analyzed. Response category structure and item fit statistics were evaluated for assessment of model fit. Person separation statistics were used to examine the validity of the subscales. Unidimensionality was assessed by principal component analysis (PCA) of model residuals. The recommended five-category response structure resulted in disordered response thresholds. A four-category structure resulted in ordered thresholds. Item infit statistics were acceptable for all 12 items. Person separation with this category structure was adequate, with a person separation index of 2.16. None of the three subscales demonstrated adequate person separation. PCA showed one other significant factor onto which the three environmental items loaded significantly. All items demonstrated acceptable fit to the model after collapsing categories to order the response thresholds. The original subscales did not prove valid, and there is some evidence of multidimensionality and poor targeting.

Assessing Differences in the Psychometric Characteristics of the Latin American and Caribbean Food Security Scale in Colombia and Mexico

The Latin American Food Security Scale (ELCSA) was applied to nationally representative samples of Colombia and Mexico (n= 13,611 and 1,560, respectively). This study explores differences in psychometric characteristics of ELCSA when applied in two different national settings. Rasch Modeling was used to assess infit and relative item severities for all questions in the scale separately in the countries. Differences in estimated item severities between the Colombian and the Mexican samples were assessed using Differential Item Functioning (DIF) models. The scale presented adequate fitness and most item infit values were within adequate range (0.8–1.2). Most items in ELCSA presented no DIF larger than 0.5 logit units, and only one item showed a DIF larger than 1.0 logit units (“socially unacceptable copying strategies”; DIF=1.22). Besides this item, households in both countries presented similar relative item severities for all other items, following similar patterns of increasing relative item severities with each item in the questionnaire. This research demonstrates that the psychometric properties of ELCSA are similar when applied in two different Latin American countries. The results of this study support the use of the proposed scale as a regional tool, but suggest also the revision of some of the items used in ELCSA for its better adaptation to diverse settings.

Health- and Vision-Related Quality of Life in Intellectually Disabled Children

To investigate the psychometric properties of instruments for the assessment of self-reported functional vision performance and health-related quality of life in children with intellectual disabilities (IDs). Two instruments [Autoquestionnaire Enfant Image (AUQUEI), LV Prasad-Functional Vision Questionnaire (LVP-FVQ)] designed for the assessment of functional vision and health-related quality of life were adapted and administered to 168 school children with ID, aged 8 to 18 years. Rasch analysis was used to determine the appropriateness of the rating scales of these instruments and to identify any redundant items. Redundant items were excluded based on descriptive statistics and Rasch analysis, leaving 17 of 23 items in the revised AUQUEI and 16 of 22 in the LVP-FVQ. The AUQUEI items showed disordered thresholds on the rating scale. A modified step calibration (collapsed from four categories to three categories) resulted in ordered response thresholds for all items. The adjusted instrument produced an overall fit to the model (mean item infit = 1.06, SD = 0.32; mean item outfit = 1.11, SD = 0.35), indicating good construct validity. After Rasch analysis, the AUQUEI showed good content validity (person separation = 2.18; item reliability = 0.99; Cronbach alpha = 0.89). Increased similarity of person and item means and SDs on the logit scale after modification would indicate that the instrument was more applicable to the target population in its modified form. In contrast, the LVP-FVQ had a low person separation (1.35), suggesting that a more appropriate instrument is needed for assessment of vision-related quality of life in children with ID. The psychometric properties of two instruments were explored using Rasch analysis. By rescaling and reduction of items, the instruments were modified for use in a population of children with at least mild to moderate ID. However, an alternative instrument is needed for the assessment of vision-related quality of life in intellectually disabled children with normal vision or mild visual abnormalities.

Experiential household food insecurity in an urban underserved slum of North India

One-third of India’s urban population resides in extreme poverty, in slums and squatters. Food insecurity remains a visible reality among this segment. Yet, it is scarcely documented. This paper describes levels and determinants of experiential household food insecurity (HFI) in an underserved urban slum of Delhi (India) and reports the internal validity and reliability of the measure used to assess experiential HFI. A four-item scale was adapted from the U.S. six-item short-form food security scale and was administered in Hindi through household interviews with 410 female adults. Association of HFI with household economic and socio-demographic characteristics were examined using multiple logistic regression. Cronbach’s alpha and Rasch-model-based item fit statistics were used to assess reliability and internal validity. Fifty-one percent of households were food insecure. Significant HFI predictors were unemployed to employed family members’ ratio of > 3:1 (Odds Ratio 2.1, Confidence Interval 1.2 – 3.4) and low household standard of living (OR 4.9, C.I. 2.7 – 8.9). Cronbach’s alpha was 0.8. Item severities as estimated under Rasch model assumptions spanned 9.7 logits. Item infit statistics (0.77 – 1.07) indicated that the Rasch model fit the data well. Item outfit statistics suggested that one item was inconsistently understood by a small proportion of respondents. For improving HFI among the urban poor, in addition to improving behaviors/entitlement access, programs should consider linkage of urban poor to existing employment schemes, upgrading of their skills and linkage to potential employers. The adapted scale was reliable and easy to administer. However, being a subjective assessment, its sensitivity to social expectation and its association with nutrition security require examination.

Gender of respondent does not affect the psychometric properties of the Brazilian Household Food Security Scale

Food insecurity is a major public concern that occurs when nutritional needs are not met, incorporates psychological and physiological coping mechanisms, and can range from basic concern over obtaining food to severe malnutrition. This study was performed to explore differences in female and male respondent psychometric characteristics of a locally adapted Brazilian Household Food Security Scale (Escala Brasileira de Medida da Insegurança Alimentar--EBIA). The 16-item EBIA was incorporated into the 2004 Brazilian National Household Sample Survey 2004 (Pesquisa Nacional por Amostra de Domicílios--PNAD; n = 108 606). Rasch Modelling was used to evaluate survey one-dimensionality, construct and independence through analysis of infit and relative item severities of adult and children items by gender. Differences in estimated item severities between male and female respondents were assessed using Differential Item Functioning (DIF) models. The scale presented good fitness and most item infit values were within adequate range (0.8-1.2), being practically identical when comparing female and male responses. Both female and male respondents presented similar relative item severities for adult and children items and followed the same pattern of increasing relative item severities with each item in the questionnaire. None of the items presented substantial DIF. This research demonstrates that the psychometric properties of the EBIA are not affected by respondent gender in Brazil. The results of this study support the validity of the proposed scale, suggesting that the scale will provide accurate information regardless of respondent gender for governments, researchers and agencies concerned with reducing epidemic levels of food insecurity and the resulting health disparities.

Dimensionality and Construct Validity of the Fugl-Meyer Assessment of the Upper Extremity

Woodbury ML, Velozo CA, Richards LG, Duncan PW, Studenski S, Lai S-M. Dimensionality and construct validity of the Fugl-Meyer Assessment of the upper extremity. Objective To investigate the dimensionality and construct validity of the Fugl-Meyer Assessment of the upper extremity by using Rasch analysis. Design Secondary analysis of pooled data from 2 existing datasets: a randomized therapeutic exercise clinical trial and a cohort longitudinal study of stroke recovery. Setting University research center. Participants A total of 512 subjects, ages 69.8±11.1 years, who were 0 to 145 days poststroke. Interventions Not applicable. Main Outcome Measures Dimensionality was examined with principal components analysis and Rasch item-fit statistics. The Rasch-derived item hierarchy was examined for consistency with the expected course of poststroke upper-extremity recovery suggested by the reflex-hierarchical conceptual model underlying the assessment. Results Factor loadings and item infit statistics suggested that the 3 reflex items were empirically disconnected from other assessment items. The reflex items were removed. The modified 30-item assessment showed a unidimensional structure. The Rasch-item-difficulty order was not consistent with the expected item order. Conclusions The items testing resting-state reflexes may threaten the assessment’s dimensionality. With reflex items removed, the assessment is a unidimensional measure of volitional movement. The Rasch-generated item-difficulty order challenges the hierarchical structure implied by the instrument’s underlying conceptual framework.

The Quality of Life Impact of Refractive Correction (QIRC) Questionnaire: Development and Validation

The purpose of the study was to develop a questionnaire that could quantify the quality of life (QOL) of people with refractive correction by spectacles, contact lenses, and refractive surgery in the prepresbyopic age group. The questionnaire was developed and validated using traditional methods and Rasch analysis. A 90-item pilot questionnaire was developed through extensive literature search and use of professional and lay focus groups. Pilot study data were obtained from 306 subjects for item reduction to produce the 20-item Quality of Life Impact of Refractive Correction (QIRC) questionnaire. Validity and reliability studies (test-retest reliability with intraclass correlation coefficient and Bland-Altman limits of agreement, and internal consistency with Rasch fit statistics, factor analysis, and Cronbach's alpha) were performed from data of an additional 312 subjects. Rasch analysis demonstrated QIRC has good precision, reliability, and internal consistency (person separation, 2.03; reliability, 0.80; root-mean-square measurement error, 3.25; mean square +/- SD infit, 0.99 +/- 0.38; outfit, 1.00 +/- 0.39; item infit range, 0.70 to 1.24; and item outfit range, 0.78 to 1.32). The items (mean score, 50.3 +/- 7.3) were well targeted to the subjects (mean score, 47.8 +/- 5.5) with a mean difference of 2.45 (scale range, 0 to 100) units. Test-retest reliability (intraclass correlation coefficient, 0.88; coefficient of repeatability, +/-6.85 units), factor loading range (0.40 to 0.76), and Cronbach's alpha (0.78) also indicated the reliability and validity of QIRC. The 20-item QIRC questionnaire, which quantifies the QOL of people with refractive correction by spectacles, contact lenses, and refractive surgery in the prepresbyopic age group, was developed using Rasch analysis and shown to be valid and reliable. The use of Rasch scaling allows scores to be treated as a valid continuous variable. QIRC has broad applicability for cross-sectional and outcomes research.