On the validity of subjective measures of company performance

Subjective measures of company performance are widely used in research and typically are interpreted as equivalent to objective measures. Yet, the assumption of equivalence is open to challenge. We compared the use of both types of measure in 3 separate samples. Findings were consistent in showing that: (a) subjective and objective measures of company performance were positively associated (convergent validity); (b) those relationships were stronger than those between measures of differing aspects of performance using the same method (discriminant validity); and (c) the relationships of subjective and objective company performance measures with a range of independent variables were equivalent (construct validity).

The Effect of nutritional supplementation on subjective and objective measures of visual and retinal function:a random controlled trial

In industrialised countries age-related macular disease (ARMD) is the leading cause of visual loss in older people. Because oxidative stress is purported to be associated with an increased risk of disease development the role of antioxidant supplementation is of interest. Lutein is a carotenoid antioxidant that accumulates within the retina and is thought to filter blue light. Increased levels of lutein have been associated with reduced risk of developing ARMD and improvements in visual and retinal function in eyes with ARMD. The aim of this randomised controlled trial (RCT) was to investigate the effect of a lutein-based nutritional supplement on subjective and objective measures of visual function in healthy eyes and in eyes with age-related maculopathy (ARM) – an early form of ARMD. Supplement withdrawal effects were also investigated. A sample size of 66 healthy older (HO), healthy younger (HY), and ARM eyes were randomly allocated to receive a lutein-based supplement or no treatment for 40 weeks. The supplemented group then stopped supplementation to look at the effects of withdrawal over a further 20 weeks. The primary outcome measure was multifocal electroretinogram (mfERG) N1P1 amplitude. Secondary outcome measures were mfERG N1, P1 and N2 latency, contrast sensitivity (CS), Visual acuity (VA) and macular pigment optical density (MPOD). Sample sizes were sufficient for the RCT to have an 80% power to detect a significant clinical effect at the 5% significance level for all outcome measures when the healthy eye groups were combined, and CS, VA and mfERG in the ARM group. This RCT demonstrates significant improvements in MPOD in HY and HO supplemented eyes. When HY and HO supplemented groups were combined, MPOD improvements were maintained, and mfERG ring 2 P1 latency became shorter. On withdrawal of the supplement mfERG ring 1 N1P1 amplitude reduced in HO eyes. When HO and HY groups were combined, mfERG ring 1 and ring 2 N1P1 amplitudes were reduced. In ARM eyes, ring 3 N2 latency and ring 4 P1 latency became longer. These statistically significant changes may not be clinically significant. The finding that a lutein-based supplement increases MPOD in healthy eyes, but does not increase mfERG amplitudes contrasts with the CARMIS study and contributes to the debate on the use of nutritional supplementation in ARM.

Representational modes of thinking employed by children aged thirteen and fourteen, and their relationship to performance in standardised tests of ability, measures of creativity and personality

This thesis proposes that despite many experimental studies of thinking, and the development of models of thinking, such as Bruner's (1966) enactive, iconic and symbolic developmental modes, the imagery and inner verbal strategies used by children need further investigation to establish a coherent, theoretical basis from which to create experimental curricula for direct improvement of those strategies. Five hundred and twenty-three first, second and third year comprehensive school children were tested on 'recall' imagery, using a modified Betts Imagery Test; and a test of dual-coding processes (Paivio, 1971, p.179), by the P/W Visual/Verbal Questionnaire, measuring 'applied imagery' and inner verbalising. Three lines of investigation were pursued: 1. An investigation a. of hypothetical representational strategy differences between boys and girls; and b. the extent to which strategies change with increasing age. 2. The second and third year children's use of representational processes, were taken separately and compared with performance measures of perception, field independence, creativity, self-sufficiency and self-concept. 3. The second and third year children were categorised into four dual-coding strategy groups: a. High Visual/High Verbal b. Low Visual/High Verbal c. High Visual/Low Verbal d. Low Visual/Low Verbal These groups were compared on the same performance measures. The main result indicates that: 1. A hierarchy of dual-coding strategy use can be identified that is significantly related (.01, Binomial Test) to success or failure in the performance measures: the High Visual/High Verbal group registering the highest scores, the Low Visual/High Verbal and High Visual/Low Verbal groups registering intermediate scores, and the Low Visual/Low Verbal group registering the lowest scores on the performance measures. Subsidiary results indicate that: 2. Boys' use of visual strategies declines, and of verbal strategies increases, with age; girls' recall imagery strategy increases with age. Educational implications from the main result are discussed, the establishment of experimental curricula proposed, and further research suggested.

Lack of association between glucocorticoid use and presence of the metabolic syndrome in patients with rheumatoid arthritis:a cross-sectional study

Introduction - Rheumatoid arthritis (RA) associates with excessive cardiovascular morbidity and mortality, attributed to both traditional and novel cardiovascular risk factors. The metabolic syndrome, a cluster of classical cardiovascular risk factors, including hypertension, obesity, glucose intolerance, and dyslipidaemia, is highly prevalent in RA. Reports suggest that long-term glucocorticoid (GC) use may exacerbate individual cardiovascular risk factors, but there have been no studies in RA to assess whether it associates with the metabolic syndrome. We examined whether GC exposure associates with the presence of metabolic syndrome in patients with RA. Methods - RA patients (n = 398) with detailed clinical and laboratory assessments were categorised into three groups according to GC exposure: no/limited (<3 months) exposure (NE), low-dose (<7.5 mg/day) long-term exposure (LE), and medium-dose (greater than or equal to 7.5 mg to 30 mg/day) long-term exposure (ME). The metabolic syndrome was defined using the National Cholesterol Education Programme III guidelines. The association of GC exposure with the metabolic syndrome was evaluated using binary logistic regression. Results - The metabolic syndrome was present in 40.1% of this population and its prevalence did not differ significantly between the GC exposure groups (NE 37.9% versus LE 40.7% versus ME 50%, P = 0.241). Binary logistic regression did not demonstrate any increased odds for the metabolic syndrome when comparing ME with LE (odds ratio = 1.64, 95% confidence interval 0.92 to 2.92, P = 0.094) and remained non significant after adjusting for multiple potential confounders. Conclusions - Long-term GC exposure does not appear to associate with a higher prevalence of the metabolic syndrome in patients with RA. The components of the metabolic syndrome may already be extensively modified by other processes in RA (including chronic inflammation and treatments other than GCs), leaving little scope for additive effects of GCs.

The effects of a lutein-based supplement on objective and subjective measures of retinal and visual function in eyes with age-related maculopathy - a randomised controlled trial

Lutein and zeaxanthin are lipid-soluble antioxidants found within the macula region of the retina. Links have been suggested between increased levels of these carotenoids and reduced risk for age-related macular disease (ARMD). Therefore, the effect of lutein-based supplementation on retinal and visual function in people with early stages of ARMD (age-related maculopathy, ARM) was assessed using multi-focal electroretinography (mfERG), contrast sensitivity and distance visual acuity. A total of fourteen participants were randomly allocated to either receive a lutein-based oral supplement (treated group) or no supplement (non-treated group). There were eight participants aged between 56 and 81 years (65·50 (sd 9·27) years) in the treated group and six participants aged between 61 and 83 years (69·67 (sd 7·52) years) in the non-treated group. Sample sizes provided 80 % power at the 5 % significance level. Participants attended for three visits (0, 20 and 40 weeks). At 60 weeks, the treated group attended a fourth visit following 20 weeks of supplement withdrawal. No changes were seen between the treated and non-treated groups during supplementation. Although not clinically significant, mfERG ring 3 N2 latency (P= 0·041) and ring 4 P1 latency (P= 0·016) increased, and a trend for reduction of mfERG amplitudes was observed in rings 1, 3 and 4 on supplement withdrawal. The statistically significant increase in mfERG latencies and the trend for reduced mfERG amplitudes on withdrawal are encouraging and may suggest a potentially beneficial effect of lutein-based supplementation in ARM-affected eyes. Copyright © 2012 The Authors.

New measures of job control, cognitive demand and production responsibility

Recent research has highlighted several job characteristics salient to employee well-being and behavior for which there are no adequate generally applicable measures. These include timing and method control, monitoring and problem-solving demand, and production responsibility. In this article, an attempt to develop measures of these constructs provided encouraging results. Confirmatory factor analyses applied to data from 2 samples of shop-floor employees showed a consistent fit to a common 5-factor measurement model. Scales corresponding to each of the dimensions showed satisfactory internal and test–retest reliabilities. As expected, the scales also discriminated between employees in different jobs and employees working with contrasting technologies.

Complexity measures of electroencephalographic data

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Are dyslexics' visual deficits limited to measures of dorsal stream function?

We tested the hypothesis that the differences in performance between developmental dyslexics and controls on visual tasks are specific for the detection of dynamic stimuli. We found that dyslexics were less sensitive than controls to coherent motion in dynamic random dot displays. However, their sensitivity to control measures of static visual form coherence was not significantly different from that of controls. This dissociation of dyslexics' performance on measures that are suggested to tap the sensitivity of different extrastriate visual areas provides evidence for an impairment specific to the detection of dynamic properties of global stimuli, perhaps resulting from selective deficits in dorsal stream functions. © 2001 Lippincott Williams & Wilkins.

Measures of process harmonization

Context Many large organizations juggle an application portfolio that contains different applications that fulfill similar tasks in the organization. In an effort to reduce operating costs, they are attempting to consolidate such applications. Before consolidating applications, the work that is done with these applications must be harmonized. This is also known as process harmonization. Objective The increased interest in process harmonization calls for measures to quantify the extent to which processes have been harmonized. These measures should also uncover the factors that are of interest when harmonizing processes. Currently, such measures do not exist. Therefore, this study develops and validates a measurement model to quantify the level of process harmonization in an organization. Method The measurement model was developed by means of a literature study and structured interviews. Subsequently, it was validated through a survey, using factor analysis and correlations with known related constructs. Results As a result, a valid and reliable measurement model was developed. The factors that are found to constitute process harmonization are: the technical design of the business process and its data, the resources that execute the process, and the information systems that are used in the process. In addition, strong correlations were found between process harmonization and process standardization and between process complexity and process harmonization. Conclusion The measurement model can be used by practitioners, because it shows them the factors that must be taken into account when harmonizing processes, and because it provides them with a means to quantify the extent to which they succeeded in harmonizing their processes. At the same time, it can be used by researchers to conduct further empirical research in the area of process harmonization.