The nutrition for sport knowledge questionnaire (NSKQ): development and validation using classical test theory and Rasch analysis

Central vascular access devices (CVADs) have become an important focus for safe practice in some patients. The aim of this study was to develop a reliable and valid knowledge questionnaire of blood sampling via CVADs for registered nurses by using both classical test theory (CTT) and Rasch analysis. A cross-sectional study was conducted, and the questionnaire was completed by 445 participants. CTT and Rasch analysis were used to measure the psychometric properties of the questionnaire. The final questionnaire consisted of 23 items. CTT analysis revealed acceptable internal reliability with Cronbach's alpha of 0.825 and content validity index (I-CVI=0.99, S-CVI/UA=0.925). Rasch analysis was conducted using a dichotomous scale, and the final 23-item questionnaire is unidimensional. The person reliability index was 0.69 with an item reliability index of 0.97. The test-retest reliability was excellent, with an intraclass correlation coefficient of 0.964. This questionnaire demonstrated a unidimensional structure and good psychological properties and was clinically meaningful for registered nurses to test their knowledge of blood sampling via CVADs. The findings represent a useful beginning for further analysis of the questionnaire in larger samples internationally.

Classical Test Theory (CTT), also known as the true score theory, refers to the analysis of test results based on test scores. The statistics produced under CTT include measures of item difficulty, item discrimination, measurement error and test reliability. The term “Classical” is used in contrast to “Modern” test theory which usually refers to item response theory (IRT). The fact that CTT was developed before IRT does not mean that CTT is outdated or replaced by IRT. Both CTT and IRT provide useful statistics to help us analyse test data. Generally, CTT and IRT provide complementary results. For many item analyses, CTT may be sufficient to provide the information we need. There are, however, theoretical differences between CTT and IRT, and many researchers prefer IRT because of enhanced measurement properties under IRT. IRT also provides a framework that facilitates test equating, computer adaptive testing and test score interpretation. While this book devotes a large part to IRT, we stress that CTT is an important part of the methodologies for educational and psychological measurement. In particular, the exposition of the concept of reliability in CTT sets the basis for evaluating measuring instruments. A good understanding of CTT lays the foundations for measurement principles. There are other approaches to measurement such as generalizability theory and structural equation modelling, but these are not the focus of attention in this book.

IntroductionSport climbing has gained increased scientific attention, including studies investigating the dietary habits and nutritional requirements of climbers; however, significant gaps in the literature remain. An assessment of nutritional knowledge, weight loss for competition, and supplement use has not been previously reported in senior competition climbing athletes.MethodsFifty climbers (26 male, 24 female; BMI 21.6 ± 1.9; 23.7 ± 5.2 years) participated in the study. Participants answered a 72-item questionnaire, comprised of demographic data and three main sections to assess general and sports nutrition knowledge, weight loss strategies, and supplement use.ResultsThe mean nutrition knowledge score was ‘average’, with considerable individual variation (53.5 ± 11.1 %). There were no significant sex differences in the general (GNK) or sport (SNK) nutrition knowledge scores, or effect of age. Significantly higher knowledge was demonstrated by national vs. international athletes for the GNK scores (11.09 ± 1.58 vs. 9.58 ± 1.75; p = 0.028). Participants scored well in questions concerning protein, carbohydrates, alcohol, and supplements, and conversely, performed poorly in hydration and micronutrient related questions. Less than one-fifth of respondents had access to a dietitian. Forty-six percent of males and 38% of female climbers reported intentional weight loss for competition on at least one occasion. Of those, ~76% reported utilizing concerning practices, including methods that conform with disordered eating and/or eating disorders, dehydration, vomiting, and misuse of laxatives. Approximately 65% of athletes reported using at least one nutritional supplement in the previous 6 months, with 44% reporting multiple supplement use. There was no significant difference in supplement use between sexes or competition level.DiscussionDue to the established importance of nutritional intake on athlete health and performance, educational support should be employed to improve knowledge in climbers and address shortcomings. Moreover, intentional weight loss for climbing competition is common, with most athletes achieving ~3–8% body weight loss over ≥2 weeks. It is crucial that professionals working with competitive climbers are vigilant in identifying athletes at risk of concerning weight management and establish referral pathways to the appropriate specialist services. High quality intervention trials to assess the efficacy of ergogenic aids in climbing remains inadequate.

Background Item response theory (IRT), particularly the graded response model, provides a latent trait (θ) that reflects balance ability and offers a complementary framework for psychometric evaluation. Although IRT is recommended for estimating clinical thresholds, its application to cutoff determination for stroke populations remains limited. We hypothesized that IRT-based approaches will yield cutoff values that differ from those derived using classical test theory and provide additional methodological insight for cutoff determination. Purpose To estimate and compare cutoff values for walking independence in inpatients with stroke using classical test theory and IRT. Methods Data from 165 inpatients with stroke were analyzed. Balance was assessed using the Brief Balance Evaluation Systems Test (Brief-BESTest). Cutoff scores were calculated using receiver operating characteristic (ROC), IRT combined with ROC (IRT+ROC), prevalence-based IRT method (old IRT), and embedded state-item IRT method (new IRT). Discriminative performance was evaluated using area under the ROC curve (AUC), sensitivity, specificity, likelihood ratios, and accuracy. Results The cutoff values for walking independence were 12.37 (ROC), 11.46 (IRT+ROC), 10.54 (old IRT), and 7.90 (new IRT). All methods demonstrated comparable performance, with AUC values ranging from 0.769 to 0.794, indicating good discriminative ability of the Brief-BESTest for identifying walking independence. The new IRT method achieved the highest AUC and sensitivity; ROC and IRT+ROC methods achieved similar AUCs. Although cutoff values and classification metrics differed slightly across methods, their confidence intervals overlapped. Conclusion To our knowledge, this is the first study to directly compare cutoff estimation methods incorporating IRT in stroke rehabilitation, suggesting that IRT-based approaches can yield cutoff values with stability comparable to that of classical test theory and providing methodological insight for future research and clinical assessment scale development.

ObjectiveSubjective motoric cognitive risk syndrome (MCR-S) is a well-established screening tool that has been validated for objective motoric cognitive risk syndrome (MCR-O) and predicted risk of incident dementia. MCR is associated with cardiovascular factors and coronary artery disease (CAD). MCR-S is crucial for remote cognitive screening but has only been validated in community settings so far. Our study aimed to validate a Chinese version of the MCR-S in CAD patients.MethodThe Chinese version of the MCR-S was obtained through a standardized forward-backward translation and cultural adaptation. 338 CAD patients were recruited. Traditional analysis based on classical test theory and Rasch analysis based on latent trait theory were performed on the MCR-S for validation. Receiver operating characteristic analysis was applied to determine the discriminative ability of MCR-S for the MCR-O in CAD patients.ResultsThe MCR-S met the unidimensionality, lack of local dependency or disordered thresholds, and good fit value for each item of the Rasch model, the item-person map shows that the item’s estimate of capacity is appropriate. MCR-S has good content validity, criterion-related validity, and test-retest reliability. An optimal cut-score of 4.6 on the MCR-S score was determined to have good sensitivity (79.2%) and specificity (71.3%) for MCR-O in CAD patients.ConclusionThe Chinese version of MCR-S meets the requirements of the Rasch model and has good validity in CAD patients. The validated MCR-S cutoff can support long-term monitoring and early intervention for CAD patients at risk of MCR-O.

Elite sport participation creates a significant burden on adolescent athletes due to demanding training schedules, high training intensities, and the complexity of puberty. As such, an athletes' ability to effectively balance stress and recovery is essential for their athletic performance and requires appropriate management throughout the competitive season. This research aimed to investigate: (i) the quantity, quality, and timing of sleep; (ii) general and sport-specific nutrition knowledge; (iii) recovery practices; and (iv) the relationships between sleep, nutrition, and recovery practices in elite adolescent athletes. A total of 51 athletes completed a battery of previously validated and reliable questionnaires which investigated their sleep characteristics, nutrition knowledge, and recovery practices. Statistically significant moderate correlations were observed between their Pittsburgh Sleep Quality Index (PSQI) global score, Sleep Difficulty Classification (SDC), and Recovery Stress Questionnaire for Athletes (REST-Q Sport) scales, with small significant correlations observed between the SDC and REST-Q recovery scales. Participants had lower scores in both their sport (36.10 ± 12.13) and total (40.25 ± 11.18) nutrition knowledge compared to their general nutrition knowledge (49.53 ± 16.46). Moderate levels of general (1.50 ± 0.86) and sport-specific (1.57 ± 0.85) stress and high levels of general (3.92 ± 0.74) and sport-specific (3.72 ± 0.96) recovery were demonstrated. Furthermore, 94% reported their sleep quality to be "fairly good" (n = 30) or "very good" (n = 18). These findings highlight the necessity of further investigating the effect of educational strategies on improving sleep, nutrition, and recovery knowledge in athletes to aid recovery and dietary behaviours.

ABSTRACTNomophobia, or the anxiety of being separated from one's mobile phone, is an emerging psychological condition in our digital age. The 20‐item Nomophobia Questionnaire (NMP‐Q) was developed to assess nomophobia symptoms. This study utilized item response theory (IRT) and classical test theory (CTT) methods to evaluate the NMP‐Q's psychometric properties. Data were collected from 5087 adults who completed the NMP‐Q. The CTT analyses included the computation of correlation coefficients, including McDonald's ω, Cronbach's α, Guttman's λ2, Guttman's λ6, greatest lower bound, average interitem correlation, Feldt–Gilmer coefficient, Feldt–Brennan coefficient, and Raju's β. IRT analyses included graded response modeling of items, test information function, differential item functioning, and reliability. CTT analysis revealed high reliability coefficients across nine metrics and a four‐factor model with good fit indices. IRT analysis showed a strong item fit to the polytomous graded model, indicating the questionnaire's robustness. Based on IRT (both uni‐ and multidimensional IRT) analyses, we propose a 10‐item short version (NMP‐Q Short), demonstrating high correlation (r = 0.97) with the original NMP‐Q. Our findings provide very good support for the NMP‐Q's reliability and construct validity. The items displayed good discrimination and difficulty parameters. The second 10 items of the NMP‐Q appeared to be the most informative. The proposed NMP‐Q Short offers a valuable option for efficient/rapid and accurate screening. However, additional validation and sensitivity testing are warranted to further establish its usefulness.

A classic topic in the fields of psychometrics and measurement has been the impact of the number of scale categories on test score reliability. This study builds on previous research by further articulating the relationship between item response theory (IRT) and classical test theory (CTT). Equations are presented for comparing the reliability and precision of scores within the CTT and IRT frameworks. This study presented new results pertaining to the relative precision (i.e., the test score conditional standard error of measurement for a given trait value) of CTT and IRT, and the new results shed light on the conditions where total scores and IRT estimates are more or less precisely measured. The relative reliability of CTT and IRT scores is examined as a function of item characteristics (e.g., locations, category thresholds, and discriminations) and subject characteristics (e.g., the skewness and kurtosis of the latent distribution). CTT total scores were more reliable when the latent distribution was mismatched with category thresholds, but the discrepancy between CTT and IRT declined as the number of scale categories increased. This article also considered the appropriateness of linear approximations of polytomous items and presented circumstances where linear approximations are viable. A linear approximation may be appropriate for items with two response options depending on the item discrimination and the match between the item location and latent distribution. However, linear approximations are biased whenever items are located in the tails of the latent distribution and the bias is larger for more discriminating items.

Pachyonychia congenita (PC) is a rare but often debilitating, dominantly inherited disorder. New treatments require more accurate instruments for evaluating changes in the quality of life in these patients. This study was undertaken to develop and validate a quality of life questionnaire for PC patients (PCQoL). Relevant factors influencing quality of life in PC patients were identified and incorporated into the well-recognized, general questionnaire, the Dermatology Life Quality Index (DLQI), to establish a disease-specific measure, the PCQoL. Classical test theory (CTT) and Rasch analysis (RA) were used to analyze and validate the PCQoL. CTT analysis established test-retest reliability and internal consistency for the PCQoL. Concurrent and construct validity for the DLQI and the PCQoL were also validated. Chi-square-based infit and outfit statistics indicated that the Rasch model fits the observed responses very well. RA reconfirmed reliability, internal consistency, reasonable homogeneity, construct validity, and the presence of three RA-based domains. The PCQoL questionnaire is a measure validated by both CTT and RA. It appears to be a valuable tool in measuring quality of life modifications in PC individuals with keratoderma.

BackgroundThe Fibromyalgia Impact Questionnaire - Revised (FIQR) is one of the most commonly used self-rating instruments developed to quantify the severity of disease burden and impact of disease on functional...

Nutrition knowledge is an important factor that influences the nutritional status and health of the individual, group or community. Research studies have been trying to develop a reliable tool which can measure nutrition-related knowledge, nutrition-related awareness and its effect on dietary behaviour. Sports nutritionists usually base their dietary interventions on a nutrition education program with dietary guidelines. There are no. of cross-sectional studies for both coaches and athletes, reporting on nutrition knowledge. Achieving optimal physical condition and maximising athletic performance both depend heavily on nutrition. Our diet provides our bodies with the energy and nutrients they need to sustain physical activity, improve muscular function, and aid in recuperation. Any physical fitness program is incomplete without nutrition as it is an integral part of physical fitness. For any sportsman, the dietary goal is to obtain adequate nutrition to improve their health and fitness or performance in sports. A carefully organized nutrition program greatly improves athletic performance. Nutritional status is a crucial factor in determining the physical fitness and training of a sports individual. For sportsmen energy requirement or nutrient requirements are high due to their game. As it is known, appropriate nutrition improves the physical performance of the sportsmen. On the other hand, inadequate intake of nutrients leads to nutrient deficiencies therefore leading to poor performance and health problems. Many studies have provided strong evidence that optimal nutrition supports physical activity, recovery and athlete performance. However Apart from less nutritional knowledge, there are several factors such as restrictive dietary intake or excessive exercise which influence healthy eating. In addition, lack of knowledge, zeal to follow a nutritious diet, lack of money and lack of time, can be a potential reason not to follow a healthy diet. Athletes generally rely on their coaches for nutrition-related guidance. So, when coaches have less knowledge about nutrition it can be a potential problem for athletes to follow a healthy diet. In some Cross-sectional studies, it is found that Coaches Play a key role in providing nutritional-related information. However, they were not aware of the importance of nutrition on performance therefore not giving the necessary importance to their diets. Coaches have inadequate knowledge about sports nutrition and their role is critical as they are prime contact for the athletes to know about their diet to enhance their performance

The authors examined the in.uence of deviant scale items (i.e., items failing to adequately assess the construct of interest) on item parameter estimates of focal scale items and person parameter estimates through a comparison of item response theory (IRT) and classical test theory (CTT) methods. The authors used monte carlo methods to fully explore results found in a pilot investigation of jobattitude data. They found that graded response model item discrimination parameter estimates were robust when the number of focal items was larger than the number of deviant items, when the focal items were more discriminating than the deviant items, and when the correlation between the focal and deviant items was positive. IRT discrimination estimates were typically more robust than CTT discrimination estimates. Under extremely unfavorable conditions, however, CTT estimates were more robust than the IRT estimates. For person parameter estimates, the robustness of estimates depended primarily on the correlation of the deviant items with the focal construct. Implications are discussed for researchers employing IRT or CTT methods in scale development.

This study is about relations between classical test theory (CTT) and item response theory (IRT). It is shown that CTT is based on the assumption that measures are exchangeable, whereas IRT is based on conditional independence. Thus, IRT is presented as an extension of CTT, and concepts from both theories are related to one another. Furthermore, it is demonstrated that IRT can be used to provide CTT statistics in situations where CTT fails. Reliability, for instance, can be determined even though a test was not administered to the intended population.

Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. Individual change assessment can be conducted using either the methodologies of classical test theory (CTT) or item response theory (IRT). Researchers have been optimistic about the possible advantages of using IRT rather than CTT in change assessment. However, little empirical evidence is available to support the alleged superiority of IRT in the context of individual change assessment. In this study, the authors compared the CTT and IRT methods with respect to their Type I error and detection rates. Preliminary results revealed that IRT is indeed superior to CTT in individual change detection, provided that the tests consist of at least 20 items. For shorter tests, however, CTT is generally better at correctly detecting change in individuals. The results and their implications are discussed.

ABSTRACTWe give an account of classical test theory (CTT) in terms of the more fundamental ideas of item response theory (IRT). This approach views CTT as a very general version of IRT, and the commonly used IRT models as detailed elaborations of CTT for special purposes. We then use this approach to CTT to derive some general results regarding the prediction of the true score of a test from an observed score on that test as well from an observed score on a different test. This leads us to a new view of linking tests that were not developed to be linked to each other. In addition we propose true‐score prediction analogues of the Dorans and Holland measures of the population sensitivity of test linking functions. We illustrate the accuracy of the first‐order theory using simulated data from the Rasch model and illustrate the effect of population differences using a set of real data.