Determining the number of factors to retain: a Windows-based FORTRAN-IMSL program for parallel analysis

Cardiorespiratory optimal point as a submaximal evaluation tool in endurance athletes: An exploratory study

Introduction: The cardiorespiratory optimal point (COP) represents the lowest minute ventilation to oxygen consumption ratio (VE/VO2) and can be estimated during a CPET at submaximal intensity when an exercise test until volitional fatigue is not always advisable (i.e., a conflict zone where you cannot be confident of the security because near-competition, off-season, among other). COP's physiological components have not been wholly described yet. Therefore, this study seeks to identify the determinants of COP in highly trained athletes and its influence on maximum and sub-maximum variables during CPET through principal c omponent analysis (PCA) (explains the dataset's variance). Methods: Female (n = 9; age, 17.4 ± 3.1 y; maximal VO2 [VO2max]), 46.2 ± 5.9 mL/kg/min) and male (n = 24; age, 19.7 ± 4.0 y; VO2max, 56.1 ± 7.6 mL/kg/min) athletes performed a CPET to determine the COP, ventilatory threshold 1 (VT1) and 2 (VT2), and VO2max. The PCA was used to determine the relationship between variables and COP, explaining their variance. Results: Our data revealed that females and males displayed different COP values. Indeed, males showed a significant diminished COP compared to the female group (22.6 ± 2.9 vs. 27.2 ±3.4 VE/VO2, respectively); nevertheless, COP was allocated before VT1 in both groups. Discussion: PC analysis revealed that the COP variance was mainly explained (75.6%) by PC1 (expired CO₂ at VO2max) and PC2 (VE at VT2), possibly influencing cardiorespiratory efficiency at VO2max and VT2. Our data suggest that COP could be used as a submaximal index to monitor and assess cardiorespiratory system efficiency in endurance athletes. The COP could be particularly useful during the offseason and competitive periods and the return to the sports continuum.

Measuring Organizational Culture in Ethiopia's Primary Care System: Validation of a Practical Survey Tool for Managers

BACKGROUND

Organizational culture has been widely recognized as predictive of health system performance and improved outcomes across various healthcare settings. Research on organizational culture in healthcare has been largely conducted in high-income settings, and validated scales to measure this concept in primary healthcare systems in low- and middle-income country (LMIC) settings are lacking. Our study aimed to validate a tool to measure organizational culture in the context of the Ethiopian Primary Healthcare Transformation Initiative (PTI), a collaborative of the Federal Ministry of Health (FMoH) and the Yale Global Health Leadership Initiative to strengthen primary healthcare system performance in Ethiopia.

METHODS

Following established survey development and adaptation guidelines, we adapted a 31-item US-based organizational culture scale using (1) cognitive interviewing, (2) testing with 1176 district and zonal health officials from four regions in Ethiopia, and (3) exploratory factor analysis (EFA).

RESULTS

Based on the results of cognitive interviewing, an adapted 30-item survey was piloted. The factor analyses of 1034 complete surveys (88% complete responses) identified five constructs of the scale which demonstrated strong validity and internal consistency: learning and problem solving, psychological safety, resistance to change, time for improvement, and commitment to the organization. Of the 30 a priori items, 26 items loaded well on the five constructs (loading values 0.40-0.86), and 4 items failed to load. Cronbach alpha coefficients were 0.86 for the scale as a whole and ranged from 0.65 to 0.90 for the subscales. The five-factor solution accounted for 62% of total variance in culture scores across respondents.

CONCLUSION

Through validation and factor analyses, we generated a 26-item scale for measuring organizational culture in public primary healthcare systems in LMIC settings. This validated tool can be useful for managers, implementers, policy-makers, and researchers to assess and improve organizational culture in support of improved primary healthcare system performance.

Senescence-associated morphological profiles (SAMPs): an image-based phenotypic profiling method for evaluating the inter and intra model heterogeneity of senescence

Senescence occurs in response to a number of damaging stimuli to limit oncogenic transformation and cancer development. As no single, universal senescence marker has been discovered, the confident classification of senescence induction requires the parallel assessment of a series of hallmarks. Therefore, there is a growing need for “first-pass” tools of senescence identification to streamline experimental workflows and complement conventional markers.

Here, we utilise a high content, multidimensional phenotypic profiling-based approach, to assess the morphological profiles of senescent cells induced via a range of stimuli. In the context of senescence, we refer to these as senescence-associated morphological profiles (SAMPs), as they facilitate distinction between senescent and proliferating cells. The complexity of the profiles generated also allows exploration of the heterogeneity both between models of senescence and within an individual senescence model, providing a level of insight at the single cell level. Furthermore, we also demonstrate that these models are applicable to the assessment of senescence in vivo, which remains a key challenge for the field. Therefore, we believe SAMPs has the potential to serve as a useful addition in the repertoire of senescence researchers, either as a first-pass tool or as part of the established senescence hallmarks.

Identifying contributing factors influencing pediatric nurses' and health professionals' self-reported collaborative practice behaviors

PURPOSE

In this study, we examined the influence of interprofessional American Heart Association (AHA) resuscitation courses on pediatric health care professionals' (N = 218) self- reported collaborative practice behaviors (CPBs) and examined differences in CPBs between nursing, medicine, and respiratory therapy.

DESIGN AND METHODS

A mixed methods explanatory design was utilized with a sample of pediatric nurses, nurse practitioners, physicians, and respiratory therapists. Data were collected using the Interprofessional Collaborative Competency Attainment Survey (ICCAS) and two open-ended questions. Data analysis included: exploratory factor analysis, paired t-tests, mixed effects modeling and directed content analysis. Inferences were made across quantitative and qualitative data.

RESULTS

Statistically significant improvement in mean CPB scores was demonstrated by all professions (t (208) = -12.76; ρ < 0.001) immediately after the AHA courses. Qualitative responses indicated physicians identified roles and responsibilities (94%, n = 17) as the most important CPB. Communication was identified by nurses (78%, n = 76), nurse practitioners (100%, n = 11) and respiratory therapists (71%, n = 5) as most important.

CONCLUSIONS

Participation in an interprofessional AHA course significantly increased mean self-reported CPB scores. Changes in mean CPB scores were sustained over 6 weeks upon return to clinical practice.

PRACTICE IMPLICATIONS

Future research focused on CPBs of front-line health care professionals can provide an accurate portrayal of an interprofessional team and can inform how collaborative practice is established in everyday clinical practice.

Development and Validation of the Gastrointestinal Unhelpful Thinking Scale (GUTs): A Brief Self-Report Measure for Clinical and Research Settings

This article describes the development and validation of the Gastrointestinal Unhelpful Thinking scale. The purpose of the research was to develop the Gastrointestinal Unhelpful Thinking scale to assess in tandem the primary cognitive-affective drivers of brain-gut dysregulation, gastrointestinal-specific visceral anxiety, and pain catastrophizing. The research involved 3 phases which included undergraduate and community samples. In the first phase, an exploratory factor analysis revealed a 15-item 2-factor (visceral sensitivity and pain catastrophizing) scale (N= 323), which then was confirmed in the second phase: N = 399, χ2(26) = 2.08, p = .001, Tucker-Lewis Index = 0.94, comparative fit index = 0.96, standardized root mean square residual = 0.05, and root mean square error of approximation = 0.07. Demonstrating convergent validity, Gastrointestinal Unhelpful Thinking scale total and subscales were strongly correlated with the modified Manitoba Index, Irritable Bowel Syndrome Symptom Severity Scale scores, Visceral Sensitivity Index, and the Pain Catastrophizing Scale. A third phase (N = 16) established test-retest reliability for the Gastrointestinal Unhelpful Thinking scale (total and subscales). The test-retest reliability correlation coefficient for the Gastrointestinal Unhelpful Thinking scale total score was .93 (p < .001) and for the subscales was .86 (p < .001) and .94 (p < .001), respectively. The Gastrointestinal Unhelpful Thinking scale is a brief psychometrically valid measure of visceral anxiety and pain catastrophizing that can be useful for both clinicians and researchers who wish to measure these thinking patterns and relate them to changes in gastrointestinal and psychological symptoms.

Developing, Implementing, and Validating a Social Toxicity Assessment Tool of Cancer

The social impact of cancer on patients and their family is well known. Yet, unlike with physical and financial toxicities, no validated tools are available to measure this impact. This study aimed at developing, validating, and implementing a novel social toxicity assessment tool for patients with cancer diagnosis (STAT-C).

Exercise training reduces brainstem oxidative stress and restores normal breathing function in heart failure

Enhanced central chemoreflex drive and irregular breathing are both hallmarks in heart failure (HF) and closely related to disease progression. Central chemoreceptor neurons located within the retrotrapezoid nucleus (RTN) are known to play a role in breathing alterations in HF. It has been shown that exercise (EX) effectively reduced reactive oxygen species (ROS) in HF rats. However, the link between EX and ROS, particularly at the RTN, with breathing alterations in HF has not been previously addressed. Accordingly, we aimed to determine: i) ROS levels in the RTN in HF and its association with chemoreflex drive, ii) whether EX improves chemoreflex/breathing function by reducing ROS levels, and iii) determine molecular alterations associated with ROS generation within the RTN of HF rats and study EX effects on these pathways. Adult male Sprague-Dawley rats were allocated into 3 experimental groups: Sham (n = 5), volume overloaded HF (n = 6) and HF (n = 8) rats that underwent EX training for 6 weeks (60 min/day, 25 m/min, 10% inclination). At 8 weeks post-HF induction, breathing patterns and chemoreflex function were analyzed by unrestrained plethysmography. ROS levels and anti/pro-oxidant enzymes gene expression were analyzed in the RTN. Our results showed that HF rats have high ROS levels in the RTN which were closely linked to the enhanced central chemoreflex and breathing disorders. Also, HF rats displayed decreased expression of antioxidant genes in the RTN compared with control rats. EX training increases antioxidant defense in the RTN, reduces ROS formation and restores normal central chemoreflex drive and breathing regularity in HF rats. This study provides evidence for a role of ROS in central chemoreception in the setting of HF and support the use of EX to reduce ROS in the brainstem of HF animals and reveal its potential as an effective mean to normalize chemoreflex and breathing function in HF.

Translation and validation of the "Questionnaire for research on keratoconus results" (KORQ) in the Colombian population

OBJECTIVE

It is proposed to carry out a process of translation and adaptation of the "Questionnaire for Research on Keratoconus Results" (KORQ) into Spanish and its validation in a Spanish-speaking population, such as Colombia. This is intended to provide a tool for measuring and monitoring the commitment to quality of life of patients with this corneal ectasia.

MATERIAL AND METHODS

A prospective analytical study was carried out, in which 200 subjects diagnosed with keratoconus completed a translated version of the KORQ questionnaire. The internal validity of the questionnaire was evaluated using Cronbach's Alpha, while its construction was evaluated by an Exploratory Factor Analysis, including a Parallel Horn Analysis for the selection of the number of underlying factors. Subsequently, 50 patients were re-selected to complete the questionnaire one week later. The repeatability of the questionnaire was measured by the Spearman test.

RESULTS

The KORQ questionnaire in its Spanish version showed some internal validity in both sections. Both sections of the questionnaire showed an essentially unidimensional behaviour. The test-retest repeatability of the test was excellent (Spearman rho> 0.95).

CONCLUSIONS

The translated version of the KORQ is valid in Colombian population.

Significant Extremal Dependence of a Daily North Atlantic Oscillation Index (NAOI) and Weighted Regionalised Rainfall in a Small Island Using the Extremogram

Extremal dependence or independence may occur among the components of univariate or bivariate random vectors. Assessing which asymptotic regime occurs and also its extent are crucial tasks when such vectors are used as statistical models for risk assessment in the field of Climatology under climate change conditions. Motivated by the poor resolution of current global climate models in North Atlantic Small Islands, the extremal dependence between a North Atlantic Oscillation index (NAOI) and rainfall was considered at multi-year dominance of negative and positive NAOI, i.e., −NAOI and +NAOI dominance subperiods, respectively. The datasets used (from 1948–2017) were daily NAOI, and three daily weighted regionalised rainfall series computed based on factor analysis and the Voronoi polygons method from 40 rain gauges in the small island of Madeira (∼740 km2), Portugal. The extremogram technique was applied for measuring the extremal dependence within the NAOI univariate series. The cross-extremogram determined the dependence between the upper tail of the weighted regionalised rainfalls, and the upper and lower tails of daily NAOI. Throughout the 70-year period, the results suggest systematic evidence of statistical dependence over Madeira between exceptionally −NAOI records and extreme rainfalls, which is stronger in the −NAOI dominance subperiods. The extremal dependence for +NAOI records is only significant in recent years, however, with a still unclear +NAOI dominance.

Measuring Students' Ability to Engage in Scientific Inquiry: A New Instrument to Assess Data Analysis, Explanation, and Argumentation

We describe the conceptualization, design, development, validation, and testing of a summative instrument that measures high school students' ability to analyze and evaluate data, construct scientific explanations, and formulate scientific arguments in biology and chemistry disciplinary contexts. Data from 1,405 students were analyzed to evaluate the properties of the instrument. Student measurement separation reliability was 0.71 with items showing satisfactory fit to the Partial Credit Model. The use of the Evidence-Centered Design framework during the design and development process provided a strong foundation for the validity argument. Additional evidence for validation were also gathered. The strengths of the instrument lie in its relatively brief time for administration and a unique approach that integrates science practice and disciplinary knowledge, while simultaneously seeking to decouple their measurement. This research models how to design assessments that align to the National Research Council's framework and informs the design of Next Generation Science Standards-aligned assessments.

Confirmatory factor analyses of the ORTO 15-, 11- and 9-item scales and recommendations for suggested cut-off scores

AIMS

To explore the validity and recommend cut-off scores in an English-speaking sample for 9, 11, and 15-item versions of the ORTO measure for orthorexia, a proposed eating disorder characterised by a pathological obsession with consuming only 'healthy' foods.

MATERIALS AND METHODS

The sample comprised of 585 participants (82.4% female) who completed an online questionnaire containing the ORTO-15, Eating Attitudes test, Obsessive Compulsive Inventory Revised. A series of Confirmatory Factor Analyses were conducted to test model fit. Binary logistic linear regression and receiver-operating-characteristics (ROC) analyses were used to obtain cut-offs.

RESULTS AND CONCLUSION

Results showed that none of the three published versions (9, 11, and 15-item) of the ORTO produced an acceptable model. Subsequent exploratory and confirmatory factor analyses yielded a seven-item version of the ORTO (ORTO-7) with a strong and stable factor structure. Analysis of cut-offs revealed that a cut-off score of equal or greater than 19 on the ORTO-7 represents probable orthorexia.

LEVEL OF EVIDENCE

Level V, descriptive study.

Aesthetics by Numbers: Links between Perceived Texture Qualities and Computed Visual Texture Properties

Our world is filled with texture. For the human visual system, this is an important source of information for assessing environmental and material properties. Indeed-and presumably for this reason-the human visual system has regions dedicated to processing textures. Despite their abundance and apparent relevance, only recently the relationships between texture features and high-level judgments have captured the interest of mainstream science, despite long-standing indications for such relationships. In this study, we explore such relationships, as these might be used to predict perceived texture qualities. This is relevant, not only from a psychological/neuroscience perspective, but also for more applied fields such as design, architecture, and the visual arts. In two separate experiments, observers judged various qualities of visual textures such as beauty, roughness, naturalness, elegance, and complexity. Based on factor analysis, we find that in both experiments, ~75% of the variability in the judgments could be explained by a two-dimensional space, with axes that are closely aligned to the beauty and roughness judgments. That a two-dimensional judgment space suffices to capture most of the variability in the perceived texture qualities suggests that observers use a relatively limited set of internal scales on which to base various judgments, including aesthetic ones. Finally, for both of these judgments, we determined the relationship with a large number of texture features computed for each of the texture stimuli. We find that the presence of lower spatial frequencies, oblique orientations, higher intensity variation, higher saturation, and redness correlates with higher beauty ratings. Features that captured image intensity and uniformity correlated with roughness ratings. Therefore, a number of computational texture features are predictive of these judgments. This suggests that perceived texture qualities-including the aesthetic appreciation-are sufficiently universal to be predicted-with reasonable accuracy-based on the computed feature content of the textures.

Quantifying the physical, social and attitudinal environment of children with cerebral palsy

PURPOSE

To develop an instrument to represent the availability of needed environmental features (EFs) in the physical, social and attitudinal environment of home, school and community for children with cerebral palsy.

METHOD

Following a literature review and qualitative studies, the European Child Environment Questionnaire (ECEQ) was developed to capture whether EFs needed by children with cerebral palsy were available to them: 24, 24 and 12 items related to the physical, social and attitudinal environments, respectively. The ECEQ was administered to parents of 818 children with cerebral palsy aged 8-12 years, in seven European countries. A domain structure was developed using factor analysis.

RESULTS

Parents responded to 98% of items. Seven items were omitted from statistical models as the EFs they referred to were available to most children who needed them; two items were omitted as they did not fit well into plausible domains. The final domains, based on 51 items, were: Transport, Physical - home, Physical - community, Physical - school, Social support - home, Social support - community, Attitudes - family and friends, Attitudes - teachers and therapists, Attitudes - classmates.

CONCLUSION

ECEQ was acceptable to parents and can be used to assess both the access children with cerebral palsy have to the EFs that they need and how available individual EFs are.

On the Dimensional Structure of Personality, Ideological Beliefs, Social Attitudes, and Personal Values

In this paper, the common dimensional-structure of measures of Big Five personality, social attitudes, personal values, conservatism, and ideological beliefs (right-wing authoritarianism and social dominance orientation) was investigated in two convenience samples of adults (Study 1, paper-and-pencil, N = 302; Study 2, Internet, N = 154). A principal components analysis resulted in a three-factor solution in both samples. In particular, a strong ideology factor emerged that can be interpreted as representing an ideological belief system. It is characterized by a right-wing, conservative orientation, social prejudice, ideological beliefs, the value orientations of self-enhancement, low self-transcendence, and the personality trait of low Openness to Experience. The other two factors comprised socially desirable personality traits and values, and a blend of personality and personal-value orientations characterized by energy, activity, openness, and curiosity, respectively. The results are interpreted in relation to recent structural and process models of personality, ideological beliefs, and social attitudes.

Development and validation of the Brazilian version of the Attitudes to Aging Questionnaire (AAQ): An example of merging classical psychometric theory and the Rasch measurement model

BACKGROUND

Aging has determined a demographic shift in the world, which is considered a major societal achievement, and a challenge. Aging is primarily a subjective experience, shaped by factors such as gender and culture. There is a lack of instruments to assess attitudes to aging adequately. In addition, there is no instrument developed or validated in developing region contexts, so that the particularities of ageing in these areas are not included in the measures available. This paper aims to develop and validate a reliable attitude to aging instrument by combining classical psychometric approach and Rasch analysis.

METHODS

Pilot study and field trial are described in details. Statistical analysis included classic psychometric theory (EFA and CFA) and Rasch measurement model. The latter was applied to examine unidimensionality, response scale and item fit.

RESULTS

Sample was composed of 424 Brazilian old adults, which was compared to an international sample (n = 5238). The final instrument shows excellent psychometric performance (discriminant validity, confirmatory factor analysis and Rasch fit statistics). Rasch analysis indicated that modifications in the response scale and item deletions improved the initial solution derived from the classic approach.

CONCLUSION

The combination of classic and modern psychometric theories in a complementary way is fruitful for development and validation of instruments. The construction of a reliable Brazilian Attitudes to Aging Questionnaire is important for assessing cultural specificities of aging in a transcultural perspective and can be applied in international cross-cultural investigations running less risk of cultural bias.

Zur Validität des Fragebogens zur Erfassung aggressiver Verhaltensweisen im Straßenverkehr (AViS)

Zusammenfassung: Für den Fragebogen zur Erfassung aggressiver Verhaltensweisen im Straßenverkehr (AViS) werden Befunde zur Konstrukt- und Kriterienvalidität (N = 841) berichtet. Die Studien zur Konstruktvalidität des AViS belegen eine theoretisch sinnvolle Einbettung verkehrsspezifischer Aggressionen in das untersuchte nomologische Netzwerk aus allgemeiner Aggression, psychologischer Reaktanz, Konfliktbewältigungsstrategien und generellen Persönlichkeitseigenschaften, wie sie mit dem EPP-D erhoben wurden. Zusammenhänge mit Indikatoren des Verkehrsverhaltens, bspw. zur Unfallbeteiligung, Verkehrsverstößen und Führerscheinentzug, belegen die Kriterienvalidität der Punktwerte des AViS. Dabei zeigte sich die Überlegenheit des AViS gegenüber allgemeinen Aggressionsmaßen.

A Validity Study of the Positive Psychology Protective Profile

The purpose of this study was to conduct an exploratory factor analysis to provide support for the construct validity of the Positive Psychology Protective Profile, a self-report measure based on positive psychology. 985 undergraduates completed the profile, the Beck Depression Inventory, and the College Life Stress Inventory. Scores on the first two factor scores (Positive Oudook, Negative Symptoms) for the profile correlated significantly with scores on depression and stress, whereas scores on the third profile factor (Problem-solving) correlated significantly only with scores on the Beck Depression Inventory. Scores on the Positive Outlook significantly differentiated participants having either chronic illness or recent major illness from those who did not.

Zur psychometrischen Optimierung einer Reaktanzskala mittels klassischer und IRT-basierter Analysemethoden

Zusammenfassung. In drei sukzessiven Studien wird eine psychometrisch ambivalente Reaktanzskala durch den kombinierten Einsatz klassischer und IRT-basierter Methoden optimiert. Während mittels herkömmlicher Faktoranalyse keine Klarheit über die Dimensionalität der Skala gewonnen wurde, konnte mit Hilfe von Mischverteilungs-Rasch-Analysen die unterschiedliche Benutzung der Antwortkategorien (Urteilstendenzen) als Quelle der unzureichenden psychometrischen Eigenschaften der Skala identifiziert werden. Daraufhin wurde die Anzahl der Antwortkategorien verringert, was in Verbindung mit einer Itemselektion zu einem eindimensionalen Messinstrument führte.

SPSS and SAS programs for determining the number of components using parallel analysis and velicer's MAP test

Popular statistical software packages do not have the proper procedures for determining the number of components in factor and principal components analyses. Parallel analysis and Velicer's minimum average partial (MAP) test are validated procedures, recommended widely by statisticians. However, many researchers continue to use alternative, simpler, but flawed procedures, such as the eigenvalues-greater-than-one rule. Use of the proper procedures might be increased if these procedures could be conducted within familiar software environments. This paper describes brief and efficient programs for using SPSS and SAS to conduct parallel analyses and the MAP test.