The Thai version of the PSS-10: An Investigation of its psychometric properties

Background  

Among the stress instruments that measure the degree to which life events are perceived as stressful, the Perceived Stress Scale (PSS) is widely used. The goal of this study was to examine the psychometric properties of a Thai version of the PSS-10 (T-PSS-10) with a clinical and non-clinical sample. Internal consistency, test-retest reliability, concurrent validity, and the factorial structure of the scale were tested.     

Cross-cultural adaption and psychometric properties of the Chinese version of the Diabetes Behavior Rating Scale: a pilot study

Self-care behavior plays a major role in diabetic management. However, in China, a satisfactory instrument has not yet been developed to evaluate the compliance of self-care behavior for young patients with type 1 diabetes mellitus(T1 DM). The Diabetes Behavior Rating Scale(DBRS) has a potential to be the first mature instrument. The purpose of this study is to cross-culturally adapt the DBRS, and preliminarily evaluate its psychometric properties. The instrument translation included translation, back translation and culture adaptation. Psychometric properties were assessed in a sample of 116 young patients with T1 DM adapting insulin injection therapy. The Chinese version of the DBRS was divided to four subscales. Cronbach's α for the total scale was 0.92. The mean inter-item and item-total correlations were 0.35 and 0.54 respectively. Test-retest reliability showed good temporal stability(r=0.81, P=0.001). Negative correlations were found between DBRS scores with the Diabetes Distress Scale scores(r=.0.32, P=0.003) and hemoglobin A1 c(HbA1 c) levels(r=.0.36, P=0.002). Higher DBRS scores correlated with better glycemic control. The Chinese insulin injection therapy version of the DBRS is well translated and culturally adapted. It shows good overall reliability and validity and appears to be a valuable tool for assessing the diabetic self-care behaviors for young patients with T1 DM.     

The psychometric properties of the Dutch version of the Telephone Interview Cognitive Status (TICS)

The Telephone Interview Cognitive Status (TICS) is an instrument to screen for dementia in older persons by telephone. Although the psychometric properties of the TICS have been studied in various countries, the quality of the Dutch version of the TICS was yet unknown. This paper presents the Dutch version of the TICS and reports on its reliability and validity among 51 patients of Maastricht University Hospital, The Netherlands. The Pearson and intra-class correlations for test-retest reliability were 0.93 and 0.92, respectively. The Pearson and intra-class correlations for inter-rater reliability were 0.91 and 0.90, respectively. Sensitivity and specificity were studied in relation to the Mini Mental State Examination (MMSE, cut-off point 23/ 24) and the diagnosis of dementia as assessed according to DSM-IV criteria. When using the TICS cut-off point of 26/27, the coefficients for sensitivity and specificity were at least 0.80. The percentages ROC under the curve were 90% and 93% with the MMSE and the diagnosis dementia as criterion, respectively. We conclude that the Dutch version of the TICS is an acceptable instrument for screening for dementia in older persons, particularly when face-to-face contact is not possible.     

Psychometric validation of the Croatian version of the Quality of Life in Epilepsy Inventory (QOLIE-31)

The primary goals of this study were to adapt the Quality of Life in Epilepsy Inventory-31 items (QOLIE-31) questionnaire to the Croatian language and to assess the translated questionnaire's psychometric properties. Translation/retranslation of the English version of the QOLIE-31 was done, and all steps for cross-cultural adaptation process were performed properly by an expert committee. Later, QOLIE-31 questionnaires and previously validated Short Form-36 (SF-36) outcome instruments were given to 200 patients with epilepsy. 172 patients (86%) responded to the first set of questionnaires, and 114 of the first time respondents (66%) returned their second survey. The two measures of reliability as internal consistency and reproducibility were determined by Cronbach alpha statistics and intraclass correlation coefficient, respectively. Concurrent validity was measured by comparing with a SF-36 questionnaire, and measurement was made using the Pearson correlation coefficient (r). The study demonstrated satisfactory internal consistency with high Cronbach a values for all of the corresponding domains (seizure worry 0.84, medication effects 0.80, emotional well-being 0.73, energy/fatigue 0.76, cognitive functioning 0.71, social functioning 0.77, overall quality of life 0.65). The intraclass correlation coefficient for six domains of QOLIE-31 questionnaire demonstrated excellent test/retest reproducibility (ICC > or = 0.75), and good test/retest reproducibility (ICC 0.71) in one domain (cognitive functioning). Considering concurrent validity, three domains had excellent correlation (r = 0.75-1), while 11 had good correlation (r = 0.50 to 0.75), and 3 had moderate correlation (r = 0.25-0.50). This study demonstrated that, if measures are to be used across cultures, the items must not only be translated well linguistically but also must be culturally adapted to maintain the content validity of the instrument at a conceptual level across different cultures. Croatian version of QOLIE-31 will be a valuable contribution to outcome measurement in epilepsy patients, particularly in the context of treatment trials, but als in a wider research context.     

Neuropsychiatric symptoms of dementia: psychometric aspects of the Dutch Neuropsychiatric Inventory (NPI)

Behavioral and psychological symptoms are highly prevalent in dementia. The Neuropsychiatric Inventory was constructed to measure these symptoms. Data from three studies are presented concerning psychometric aspects of the NPI Dutch version. The NPI was compared to the Revised Memory and Behavioral Problems Checklist (RMBPC) and the Mini Mental State Examination (MMSE). In the three selected patient samples prevalence of behavioral or psychological symptoms was as high as 90%. Interrater agreement (n = 19) was very high (kappa > .90). Factor analysis (n = 199) supports NPI construct validity. The NPI items correlated reasonably high (R = .35 - .60) with the relevant RMBPC subscales (n = 24). Although some NPI items did, the NPI total score was not significantly related to the MMSE. The NPI Dutch version can be scored objectively and it is a valid rating scale for measuring a wide range of behavioral and psychological symptoms of dementia.     

Relationship between functional properties and structure of ovalbumin

The effects of ovalbumin (OVA) denaturation using urea, guanidinium chloride (GdnHCl), sodium dodecyl sulphate (SDS), cetylpyridinium chloride (CPC), 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS), and 5 different cationic detergents with various side chains, HCl, and CH₃COOH were observed. Progressive unfolding in ovalbumin was measured as a function of fluorescent light intensity, peak response and shift in the maximum of emission. Kinetic measurements demonstrated that the rate of denaturation usually followed a double exponential decay pattern, but at small concentrations of urea and acids first-order reaction was indicated. The reversibility of the unfolding-folding transitions was confirmed from tryptophan fluorescence and circular dichroism (CD) measurements. Differences in secondary structure were observed and changes of-helical content were calculated. Polyacrylamide gel electrophoresis (PAGE) with and without sodium dodecyl sulphate (SDS-PAGE) showed differences in the structure of native and denatured ovalbumin. Native protein samples in PAGE demonstrated smaller number and larger mobilities of subunits than denatured ones with different reductants, such as SDS and 2-mercaptoethanol (2 ME). Scanning of SDS protein patterns showed the appearance of aggregated forms in region of 45 kD.     

Letter fluency: psychometric properties and Dutch normative data

Normative data were collected for a Dutch version of the Controlled Oral Word Association Test (COWAT) in 200 healthy subjects between 17 and 89 years of age. The COWAT is a letterfluency task that is widely used in clinical neuropsychology. Fluency is an important aspect of executive functioning. The psychometric properties of the Dutch version of the test were largely comparable to those of the original COWAT. Its reliability is 0.80, and its scores are significantly related to level of education and/or vocabulary, but not to age or gender. A regression formula is provided by which the raw scores can be corrected for level of education.     

Validation of a French version of the Freiburg Mindfulness Inventory - short version: relationships between mindfulness and stress in an adult population

Background  

Whereas interest in incorporating mindfulness into interventions in medicine is growing, data on the relationships of mindfulness to stress and coping in management is still scarce. This report first presents a French validation of the Freiburg Mindfulness Inventory-short form (FMI) in a middle-aged working population. Secondly, it investigates the relationship between psychological adjustment and mindfulness.     

Improving psychometric assessment of the Beck Depression Inventory using Multidimensional Item Response Theory

We studied the latent factor structure of the Beck Depression Inventory (BDI) under the light of Multidimensional Item Response Theory models. Under a Bayesian Markov chain Monte Carlo setting, we chose the most adequate model, estimated its parameters and verified its fit to the data. An evaluation of the inventory in terms of the assumed dimensions seems to agree with previous investigations in the factor structure of the BDI present in the literature. Cognitive and somatic‐affective latent traits were identified in the analysis making possible the interpretation of symptom evolution along these dimensions, in terms of probability of their appearance.     

Initial psychometric characterization for the Portuguese version of the Morningness-Eveningness-Stability-Scale improved (MESSi)

ABSTRACT

This work reports the initial psychometric characterization of the Morningness-Eveningness-Stability-Scale improved (MESSi) for Portuguese young-adults (N = 466). A confirmatory factor analysis confirmed a three-factor model (i.e. Morning Affect, Eveningness and Distinctness) in our data, as originally proposed. Furthermore, construct validity evidence in relation to external variables (i.e. morningness/eveningness and satisfaction with life), as well as adequate reliability (i.e. internal consistency and test-retest reliability), were found. Finally, sex-based invariance and between-sex differences were investigated for the three subscales, as were correlations with age. Results point to the suitability of the MESSi for multi-cultural research on relevant and multiple aspects of chronotype.     

Development and psychometric testing of a theory-based tool to measure self-care in diabetes patients: the Self-Care of Diabetes Inventory

Background

Self-care is essential for patients with diabetes mellitus. Both clinicians and researchers must be able to assess the quality of that self-care. Available tools have various limitations and none are theoretically based. The aims of this study were to develop and to test the psychometric properties of a new instrument based on the middle range-theory of self-care of chronic illness: the Self-Care of Diabetes Inventory (SCODI).

Methods

Forty SCODI items (5 point Likert type scale) were developed based on clinical recommendations and grouped into 4 dimensions: self-care maintenance, self-care monitoring, self-care management and self-care confidence based on the theory. Content validity was assessed by a multidisciplinary panel of experts. A multi-centre cross-sectional study was conducted in a consecutive sample of 200 type 1 and type 2 diabetes patients. Dimensionality was evaluated by exploratory factor analyses. Multidimensional model based reliability was estimated for each scale. Multiple regression models estimating associations between SCODI scores and glycated haemoglobin (HbA1c), body mass index, and diabetes complications, were used for construct validity.

Results

Content validity ratio was 100%. A multidimensional structure emerged for the 4 scales. Multidimensional model-based reliabilities were between 0.81 (maintenance) and 0.89 (confidence). Significant associations were found between self-care maintenance and HbA1c (p?=?0.02) and between self-care monitoring and diabetes complications (p?=?0.04). Self-care management was associated with BMI (p?=?0.004) and diabetes complications (p?=?0.03). Self-care confidence was a significant predictor of self-care maintenance, monitoring and management (all p?<?0.0001).

Conclusion

The SCODI is a valid and reliable theoretically-grounded tool to measure self-care in type 1 and type 2 DM patients.

     

Psychometric properties and accuracy of the European Portuguese version of the Pittsburgh Sleep Quality Index in clinical and non-clinical samples

To assess the reliability and validity concerning the formal European Portuguese version of the Pittsburgh Sleep Quality Index [PSQI (EP)], its accuracy, and optimal cut-off point. N = 564 volunteers (18–80 years old) recruited in several settings (e.g., university campuses; work place; home; sleep consultations), agreed to complete the PSQI (EP). Subgroups completed additional measures: Insomnia Severity Index (ISI), STOP-Bang, Glasgow Sleep Effort Scale, or responded to a supplementary question about perceived sleep problems. As to internal consistency, Cronbach’s α = 0.75. Principal component analysis revealed a unidimensional structure. Six PSQI (EP) components and total scores were able to discriminate individuals who did versus did not describe having any sleep problem; all PSQI (EP) scores were significantly higher (denoting poorer quality) in participants suffering from a sleep disorder. Most Cohen’s d values showed large magnitude associations. PSQI (EP) and ISI scores were highly correlated, but no significant correlations were found considering STOP-Bang. ROC analysis confirmed an optimal cut-off point > 5 of the PSQI (EP) to detect self-reported poor/good sleepers in non-clinical settings. To discriminate non-clinical from clinical sleep patients, the optimal cutoff was > 7, and AUC = 0.94. The European Portuguese version of the PSQI performs as a reliable, valid, and accurate measure of overall sleep quality in Portuguese participants. Furthermore, results suggest that PSQI (EP) can discriminate poor sleepers in non-clinical settings, in addition to demonstrating high clinical accuracy in signaling potential sleep-disorder cases. In conclusion, the PSQI (EP) is a suitable tool to assess general sleep quality in Portuguese participants, both for clinical or non-clinical applications.

     

Relationship between mechanical properties and collagen structure of closed and open wounds

Mechanical properties and collagen structure of excisional wounds left open are compared with wounds closed by clips. In both wound models, collagen fiber diameter increases with time post-wounding and is related to tensile strength. Clipped wounds show a higher ultimate tensile strength and tangent modulus compared with open wounds. In clipped wounds, newly deposited collagen appears as a biaxially oriented network as observed in normal skin. In open wounds a delay in the organization of the collagen network is observed and parallel wavy-shaped ribbons of collagen fibers are deposited. At long term, the high extensibility observed in open wounds may be due to the sliding of ribbons of collagen fibers past each other.     

Validating the use of database potentials in protein structure determination by NMR

The refinement of protein structures determined by nuclear magnetic resonance spectroscopy against database potentials of mean force allows for the exclusion of unfavourable conformations of the protein backbone during a structure calculation, resulting in protein structures with a marked improvement in Ramachandran statistics. In this communication, we use multiple sets of residual dipolar couplings as quality assessment criteria for several proteins and show that not only do the Ramachandran and structural quality statistics improve, but a significant improvement in the accuracy of structures is achieved upon refinement.     

The Revised Fibromyalgia Impact Questionnaire (FIQR): validation and psychometric properties

Introduction  

The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR.     

Enhancing and confirming the specificity of RNAi experiments

RNA interference (RNAi) provides a powerful technique for the derivation and analysis of loss-of-function phenotypes in vertebrate cells, where alternative approaches are either arduous or frequently ineffective. RNAi, however, is not always totally specific, and confirming the specificity, and hence the validity, of data obtained using RNAi therefore forms an essential component of experiments that rely on this technique. Here I briefly review the potential pitfalls associated with RNAi, and then suggest experimental approaches that can be used to maximize the specificity of RNAi or to confirm that the data obtained are indeed valid.