A comparison of two time-domain analysis procedures in the determination of VO2 kinetics by pseudorandom binary sequence exercise testing

The purpose of this study was to apply and compare two time-domain analysis procedures in the determination of oxygen uptake (VO2) kinetics in response to a pseudorandom binary sequence (PRBS) exercise test. PRBS exercise tests have typically been analysed in the frequency domain. However, the complex interpretation of frequency responses may have limited the application of this procedure in both sporting and clinical contexts, where a single time measurement would facilitate subject comparison. The relative potential of both a mean response time (MRT) and a peak cross-correlation time (PCCT) was investigated. This study was divided into two parts: a test-retest reliability study (part A), in which 10 healthy male subjects completed two identical PRBS exercise tests, and a comparison of the VO2 kinetics of 12 elite endurance runners (ER) and 12 elite sprinters (SR; part B). In part A, 95% limits of agreement were calculated for comparison between MRT and PCCT. The results of part A showed no significant difference between test and retest as assessed by MRT [mean (SD) 42.2 (4.2) s and 43.8 (6.9) s] or by PCCT [21.8 (3.7) s and 22.7 (4.5) s]. Measurement error (%) was lower for MRT in comparison with PCCT (16% and 25%, respectively). In part B of the study, the VO2 kinetics of ER were significantly faster than those of SR, as assessed by MRT [33.4 (3.4) s and 39.9 (7.1) s, respectively; P<0.01] and PCCT [20.9 (3.8) s and 24.8 (4.5) s; P < 0.05]. It is possible that either analysis procedure could provide a single test measurement Of VO2 kinetics; however, the greater reliability of the MRT data suggests that this method has more potential for development in the assessment Of VO2 kinetics by PRBS exercise testing.

Testing of disability identification tool for schools

There has been an ongoing concern about the lack of reliable data on disabled children in schools. To date there has been no consistent way of identifying and categorising disabilities. Schools in England are currentlyrequired to collect data on children with Special Educational Need (SEN), but this does not capture information about all disabled children. The lack of this information may seriously restrict capacity at all levels of policy and practice to understand and respond to the needs of disabled children and their families in line with Disability Discrimination Act (2005) and the single Equality Act (2010). The aim of the project was to test the draft tools for identifying disability and accompanying guidance in a sample of all types of maintained schools in order to assess their usability and reliability and whether they resulted in the generation of robust and consistent data that could reliably inform school returns for the annual School Census.

Hypotheses testing for structural calibration model

The main objective of this paper is to discuss maximum likelihood inference for the comparative structural calibration model (Barnett, in Biometrics 25:129-142, 1969), which is frequently used in the problem of assessing the relative calibrations and relative accuracies of a set of p instruments, each designed to measure the same characteristic on a common group of n experimental units. We consider asymptotic tests to answer the outlined questions. The methodology is applied to a real data set and a small simulation study is presented.

Testing hypotheses in the Birnbaum-Saunders distribution under type-II censored samples

The two-parameter Birnbaum-Saunders distribution has been used successfully to model fatigue failure times. Although censoring is typical in reliability and survival studies, little work has been published on the analysis of censored data for this distribution. In this paper, we address the issue of performing testing inference on the two parameters of the Birnbaum-Saunders distribution under type-II right censored samples. The likelihood ratio statistic and a recently proposed statistic, the gradient statistic, provide a convenient framework for statistical inference in such a case, since they do not require to obtain, estimate or invert an information matrix, which is an advantage in problems involving censored data. An extensive Monte Carlo simulation study is carried out in order to investigate and compare the finite sample performance of the likelihood ratio and the gradient tests. Our numerical results show evidence that the gradient test should be preferred. Further, we also consider the generalized Birnbaum-Saunders distribution under type-II right censored samples and present some Monte Carlo simulations for testing the parameters in this class of models using the likelihood ratio and gradient tests. Three empirical applications are presented. (C) 2011 Elsevier B.V. All rights reserved.

Swedish translation and psychometric testing of the safety attitudes questionnaire (operating room version)

Background: Tens of millions of patients worldwide suffer from avoidable disabling injuries and death every year. Measuring the safety climate in health care is an important step in improving patient safety. The most commonly used instrument to measure safety climate is the Safety Attitudes Questionnaire (SAQ). The aim of the present study was to establish the validity and reliability of the translated version of the SAQ. Methods: The SAQ was translated and adapted to the Swedish context. The survey was then carried out with 374 respondents in the operating room (OR) setting. Data was received from three hospitals, a total of 237 responses. Cronbach's alpha and confirmatory factor analysis (CFA) was used to evaluate the reliability and validity of the instrument. Results: The Cronbach's alpha values for each of the factors of the SAQ ranged between 0.59 and 0.83. The CFA and its goodness-of-fit indices (SRMR 0.055, RMSEA 0.043, CFI 0.98) showed good model fit. Intercorrelations between the factors safety climate, teamwork climate, job satisfaction, perceptions of management, and working conditions showed moderate to high correlation with each other. The factor stress recognition had no significant correlation with teamwork climate, perception of management, or job satisfaction. Conclusions: Therefore, the Swedish translation and psychometric testing of the SAQ (OR version) has good construct validity. However, the reliability analysis suggested that some of the items need further refinement to establish sound internal consistency. As suggested by previous research, the SAQ is potentially a useful tool for evaluating safety climate. However, further psychometric testing is required with larger samples to establish the psychometric properties of the instrument for use in Sweden.

Translating and testing the Alberta Context Tool for use among nurses in Swedish elder care

Background. There is emerging evidence that context is important for successful transfer of research knowledge into health care practice. The Alberta Context Tool (ACT) is a Canadian developed research-based instrument that assesses 10 modifiable concepts of organizational context considered important for health care professionals’ use of evidence. Swedish and Canadian health care have similarities in terms of organisational and professional aspects, suggesting that the ACT could be used for measuring context in Sweden. This paper reports on the translation of the ACT to Swedish and a testing of preliminary aspects of its validity, acceptability and reliability in Swedish elder care. Methods. The ACT was translated into Swedish and back-translated into English before being pilot tested in ten elder care facilities for response processes validity, acceptability and reliability (Cronbach’s alpha). Subsequently, further modification was performed. Results. In the pilot test, the nurses found the questions easy to respond to (52%) and relevant (65%), yet the questions’ clarity were mainly considered ‘neither clear nor unclear’ (52%). Missing data varied between 0 (0%) and 19 (12%) per item, the most common being 1 missing case per item (15 items). Internal consistency (Cronbach’s Alpha > .70) was reached for 5 out of 8 contextual concepts. Translation and back translation identified 21 linguistic- and semantic related issues and 3 context related deviations, resolved by developers and translators. Conclusion. Modifying an instrument is a detailed process, requiring time and consideration of the linguistic and semantic aspects of the instrument, and understanding of the context where the instrument was developed and where it is to be applied. A team, including the instrument’s developers, translators, and researchers is necessary to ensure a valid translation. This study suggests preliminary validity, reliability and acceptability evidence for the ACT when used with nurses in Swedish elder care.

Design, format, validity and reliability of mutiple choice questions for use in nursing research and education

Multiple choice questions are used extensively in nursing research and education and play a fundamental role in the design of research studies or educational programs. Despite their widespread use, there is a lack of evidence-based guidelines relating to design and use of multiple choice questions. Little is written about their format, structure, validity and reliability of in the context of nursing research and/or education and most of the current literature in this area is based on opinion or consensus. Systematic multiple choice question design and use of valid and reliable multiple choice questions are vital if the results of research or educational testing are to be considered valid. Content and face validity schould be established by expert panel review and construct validity should be established using ‘key check’, item discrimination and item difficulty analyses. Reliability measures include internal consistency and equivalence. Internal consistency should be established by determination of internal consistency using reliability coefficients while equivalence should be established using alternate form correlation. This paper reviews literature related to the use of multiple choice questions, current design recommendations and processes to establish reliability and validity, and discusses implications for their use in nursing research and education.

Vocational learners: testing readiness for online learning

McVay's (2000) Readiness for Online Learning questionnaire is tested for its potential value as an instrument to assess the readiness for online learning of technical level and of university level vocational learners. The research indicates that the instrument yields a reliable factor structure that is replicable across the two learner groups, and is interpretable in a context of broader research and theory on flexible learning. Although the reliability of the instrument and its items is acceptable for the university level sample, reliability was less than acceptable for the technical level learners. The utility of the instrument is discussed for each of these samples of learners.

Evaluation of cervial range of motion and isometric nech muscle strngth: reliability and validity

Objective: To examine the test–retest reliability and construct validity of cervical active range of motion and isometric neck muscle strength as measured by the Multi Cervical Rehabilitation Unit (Hanoun Medical Inc., Ontario).
Design: A cross-sectional study.
Setting: Institutional practice.
Subjects: Twenty-one patients with neck pain and 25 healthy volunteers.
Methods: After a trial-run session, active range of motion (AROM) was measured in the subsequent two sessions, with 2–3 days in between. During each session, three measurements were taken for each direction (flexion, extension, lateral flexions and rotations). The measurement of isometric strength was after a 15-minute break following completion of the measurement of AROM. Three measurements were made for each of the six directions (flexion, extension, lateral flexions, protraction and retraction). The software of the Multi Cervical Rehabilitation Unit automatically recorded and calculated the maximum AROM and isometric strength.
Results: There was a good to high level of reliability in the measurement of AROM for both groups of subjects, with intraclass correlation coefficients (ICCs) ranging from 0.81 to 0.96. Results also demonstrated very good to excellent reliability in isometric strength measurement (ICCs ranged from 0.92 to 0.99). Moreover, there was a significant difference in isometric neck muscle strength (p = 0.001) and in AROM (p = 0.034) between the two groups.
Conclusions: The Multi Cervical Rehabilitation Unit was found to be reliable and valid for testing the cervical active range of motion and isometric neck muscle strength for both normal and patient subjects.

Testing the psychometric properties of Clary's volunteer motivation scale with online panel members

Academic researchers, industry and policy-makers are increasingly using online panels as a means for data collection for their research. Online panels are frequently constituted by volunteers who can choose to accept offers to participate in research (cf. voluntary opt-in Cooper 2000). This research focuses on the importance volunteering as the primary reason as to why individuals decide to become panel members. In so doing, we tested the psychometric properties of Clary et al. 's (1998) Volunteer Functions Inventory (VFI) making use of confirmatory factor analyses and ascertained that the dimensions exhibit adequate levels of reliability and validity in an online panel member's milieu.

Reliability of normalisation methods for EMG analysis of neck muscles

Acceptable reliability of normalisation contractions in electromyography (EMG) is paramount for testing conducted over a number of days or if normal laboratory strength testing equipment is unavailable. This study examined the reliability of maximal voluntary isometric contractions (MVIC) and sub-maximal (60%) isometric contractions for use in neck muscle EMG studies. Surface EMG was recorded bilaterally from eight sites around the neck at C4/5 level from five healthy male subjects. Subjects performed MVIC and sub-maximal normalisation contractions using an isokinetic dynamometer (ID) and a portable cable dynamometer with attached strain gauge (PCD) in addition to a MVIC against a manual resistance (MR). Subjects were tested in flexion, extension, left and right lateral bending and were retested by the same tester within a two-week period. Intra class correlation co-efficients (ICC) were calculated for each testing method and contraction direction and a mean ICC was calculated across all contraction directions. All normalisation methods produced excellent within-day reliability (mean ICC >0.80) but only the MVICs using the ID and PCD had acceptable reliability when assessed between-days. This study confirmed the validity of using MVICs elicited using the ID and PCD as reliable reference contractions for the normalisation of neck EMG.