Determinants of health-related quality of life in people with Parkinson’s disease: a path analysis

Purpose:
To identify the demographic factors, impairments and activity limitations that contribute to health-related quality of life (HRQOL) in people with idiopathic Parkinson’s disease (PD).

Method:
Two hundred and ten individuals with idiopathic PD who participated in the baseline assessment of a randomized clinical trial were included. The Parkinson’s Disease Questionnaire-39 summary index was used to quantify HRQOL. In order to provide greater clarity regarding the determinants of HRQOL, path analysis was used to explore the relationships between the various predictors in relation to the functioning and disability framework of the International Classification of Functioning model.

Results:
The two models of HRQOL that were examined in this study had a reasonable fit with the data. Activity limitations were found to be the strongest predictor of HRQOL. Limitations in performing self-care activities contributed the most to HRQOL in Model 1 (β = 0.38; p < 0.05), while limitations in functional mobility had the largest contribution in Model 2 (β = −0.31; p < 0.0005). Self-reported history of falls was also found to have a significant and direct relationship with HRQOL in both models (Model 1 β = −0.11; p < 0.05; Model 2 β = −0.21; p < 0.05).

Conclusions:
Health-related quality of life in PD is associated with self-care limitations, mobility limitations, self-reported history of falls and disease duration. Understanding how these factors are inter-related may assist clinicians focus their assessments and develop strategies that aim to minimize the negative functional and social sequelae of this debilitating disease.

Perceptions of public security in post-reform urban China: a routine activity analysis

This paper investigates the personal and environmental determinants of public security perceptions across 32 Chinese cities within the risk/opportunity framework of Cohen and Felson's (American Sociological Review 44:588-608, 1979) routine activity theory. Structural path analysis reveals that public security perceptions in China are informed by similar personal and environment characteristics to those reported as important in extant research within Western contexts. However, the frequently reported influence of gender on public security perceptions in the West does not appear to extend to post-reform urban China. The results provide support for the routine activity theory in terms of extending our understanding of the factors that influence perceptions of public security to a non-Western context. © 2009 Springer Science+Business Media B.V.

A path model of psychosocial and health behaviour change predictors of excessive gestational weight gain

This study aimed to evaluate a conceptual model of psychosocial, behaviour change, and behavioural predictors of excessive gestational weight gain (GWG). Background: Excessive GWG can place women and their babies at risk of poor health outcomes, including obesity. Models of psychosocial and behaviour change predictors of excessive GWG have not been extensively explored; understanding the mechanisms leading to excess GWG will provide crucial evidence towards the development of effective interventions. Method: Two hundred and eighty-eight pregnant women (≤18 weeks gestation) were recruited to a prospective study. Demographic, psychosocial, health behaviour change, and behavioural factors were assessed at 17 (Time 1, T1) and 33 weeks (Time 2, T2) gestation. Pre-pregnancy and final pregnancy weight were obtained and women were classified with/without excessive GWG. Logistic regressions refined the list of predictors of excessive GWG; variables with p < .1 were included in a path analysis. Results: Age, family income, T2 depression, T2 pregnancy-specific coping, T1 buttocks dissatisfaction, T2 GWG-specific self-efficacy, T1 dietary readiness, T1 dietary importance, and T1 vegetable intake predicted excessive GWG in the logistic regressions and were included in the path model. The baseline path model demonstrated poor fit. Once statistically and theoretically plausible paths were added, adequate model fit was achieved (χ² = 21.61(9), p < .05; RMSEA = .07; CFI = .93); this revised model explained 19.5% of the variance in excessive GWG. Women with high T1 buttocks dissatisfaction were more likely to exhibit low levels of dietary readiness. Women with low dietary readiness were more likely to have a lower vegetable intake, which predicted excessive GWG. Women with higher T2 depressive symptoms were more likely to report lower GWG self-efficacy and gain excessively. Conclusion: Future behavioural GWG trials should consider combining psychosocial and health behaviour change factors to optimise GWG.

An exploration of the relationships between food lifestyle and vegetable consumption

A short questionnaire was completed by 276 South Australian consumers, which examined postulated relationships between personal values, food lifestyle, demographics and their usual consumption of 24 vegetables. Principal components analyses showed that consumers' vegetable consumption could be divided into several categories, most notably salad and boiled vegetables. In multiple regression analyses different sets of values and lifestyle factors predicted intakes of overall vegetable (Rsq=27 per cent), salad (16 per cent) and boiled (27 per cent) vegetables. Path analysis revealed a complex set of pathways leading from values and personal demographics through motives, perceived food attributes and cooking skills to consumption. These partly confirmed the food lifestyle model proposed by Grunert et al. The findings show that vegetable consumption has a number of contextual and cognitive antecedents but strongly suggest that other likely predictive variables require investigation.

Embodied energy in buildings : wood versus concrete - reply to Börjesson and Gustavsson

We analyse the wood and concrete designs of the Wälludden building described by Börjesson et al. (Energy Policy 28 (2000) 575) in terms of their embodied energy, employing an environmentally extended input–output framework in a tiered hybrid life-cycle assessment, and in a structural path analysis. We illustrate the complexity of the inter-industry supply chains underlying the upstream energy requirements for the building options, and demonstrate that higher-order inputs are difficult to capture in a conventional process analysis. Our calculations show that Börjesson and Gustavsson's estimates of energy requirements and greenhouse gas emissions are underestimated by a factor of about 2, and that corresponding greenhouse gas balances are positive at about 30 t C-eq. Nevertheless, Börjesson and Gustavsson's general result—the concrete-framed building causing higher emissions—still holds.

Hierarchical relationship between values, lifestyles, possessions and food consumption among Beijing adult population

A representative sample (N=801) of the Beijing adult population was used to empirically test and validate a proposed hierarchical model of relationships between values, lifestyles, possessions and food consumption. The theoretical contribution of the present study is the development and an empirically supported paradigm, which explains consumers' consumption behaviour. A further outcome is the substantiation of a pathway model involving hierarchical relationship between values, lifestyle, and demographic variables on material possessions and food consumption.

How can managers reduce employee intention to quit?

This paper reports on an investigation of the variables that may be predictive of intentions to leave a job, and tests a model that includes mediating variables. A total of 173 retail salespeople completed questionnaires measuring commitment to the organization for which they worked, job satisfaction, stress, supervisor support, locus of control, self-esteem, the perceived stressors in the job and their intention to quit. Path analysis was used to test the relationships hypothesized in the model. The majority of hypotheses were supported, with the variables included accounting for 52 per cent of the variance in intention to quit. Emotional support from supervisors and self-esteem mediated the impact of stressors on stress reactions, job satisfaction, commitment to the organization and intention to quit. It is suggested that to ameliorate intention to quit and in turn reduce turnover, managers need to actively monitor workloads, and the relationships between supervisors and subordinates in order to reduce and manage stress. Managers also need to monitor both the extrinsic and intrinsic sources of job satisfaction available to employees. These activities could assist in maintaining and increasing job satisfaction and commitment to the organization.

Same strategic HRM issues predict performance in both for-profit and non-profit organizations in a key knowledge-intensive industry

This paper examines the adoption of strategic human resource management (HRM) by for-profit and non-profit knowledge-intensive health services (HS) organisations in Australia. Survey data collected from senior executives is used to test the relationships between a strategic HRM model and firm performance. Path analysis found that, irrespective of whether for-profit or non-profit, adopting strategic HRM could increase organisational performance. Strategic HRM could be achieved through the cultivation of an external orientation to customers’ demands and an internal orientation highlighting commitment to employees. Public and non-profit organisations in the HS industry facing or undergoing health sector reform need to be aware of both of these orientations in order to adopt strategic HRM and improve their performance.

Strategic HRM in for-profit and non-profit organizations in a knowledge-intensive industry

This article examines the adoption of strategic Human Resource Management (HRM) by for-profit and non-profit knowledge-intensive health services (HS) organizations in the Australian context. Survey data collected from senior executives are used to test the relationships between a strategic HRM model and firm performance. Path analysis found that for HS firms, irrespective of whether for-profit or non-profit, adopting strategic HRM could increase organizational performance. Strategic HRM could be achieved through the cultivation of an external orientation to customers' demands and a commitment to employees. Building an external orientation with internal structural dimensions such as commitment to employees, allows HS organizations to develop a strategic HRM approach with human capital-enhancing HRM practices. Public and non-profit organizations in the HS industry facing or undergoing health sector reform need to be aware of both of these orientations in order to adopt strategic HRM and improve their performance.

Investigation of the effects of microcomputers on the work of professional accountants

Information technology research over the past two decades suggests that the installation and use of computers fundamentally affects the structure and function of organisations and, m particular, the workers in these organizations. Following the release of the IBM Personal Computer in 1982, microcomputers have become an integral part of most work environments. The accounting services industry, in particular, has felt the impact of this ‘microcomputer revolution’. In Big Six accounting firms, there is almost one microcomputer for each professional accountant employed, Notwithstanding this, little research has been done on the effect of microcomputers on the work outcomes of professional accountants working in these firms. This study addresses this issue. It assesses, in an organisational setting, how accountant’ perceptions of ease of use and usefulness of microcomputers act on their computer anxieties, microcomputer attitudes and use to affect their job satisfaction and job performance. The research also examines how different types of human-computer interfaces affect the relationships between accountants' beliefs about microcomputer utility and ease of use, computer anxiety, microcomputer attitudes and microcomputer use. To attain this research objective, a conceptual model was first developed, The model indicates that work outcomes (job satisfaction and job performance) of professional accountants using microcomputers are influenced by users' perceptions of ease of use and usefulness of microcomputers via paths through (a) the level of computer anxiety experienced by users, (b) the general attitude of users toward using microcomputers, and (c) the extent to which microcomputers are used by individuals. Empirically testable propositions were derived from the model to test the postulated relationships between these constructs. The study also tested whether or not users of different human-computer interfaces reacted differently to the perceptions and anxieties they hold about microcomputers and their use in the workplace. It was argued that users of graphical interfaces, because of the characteristics of those interfaces, react differently to their perceptions and anxieties about microcomputers compared with users of command-line (or textual-based) interfaces. A passive-observational study in a field setting was used to test the model and the research propositions. Data was collected from 164 professional accountants working in a Big Six accounting firm in a metropolitan city in Australia. Structural equation modelling techniques were used to test the, hypothesised causal relationships between the components comprising the general research model. Path analysis and ordinary least squares regression was used to estimate the parameters of the model and analyse the data obtained. Multisample analysis (or stacked model analysis) using EQS was used to test the fit of the model to the data of the different human-computer interface groups and to estimate the parameters for the paths in those different groups. The results show that the research model is a good description of the data. The job satisfaction of professional accountants is directly affected by their attitude toward using microcomputers and by microcomputer use itself. However, job performance appears to be only directly affected by microcomputer attitudes. Microcomputer use does not directly affect job performance. Along with perceived ease of use and perceived usefulness, computer anxiety is shown to be an important determinant of attitudes toward using microcomputers - higher levels of computer anxiety negatively affect attitudes toward using microcomputers. Conversely, higher levels of perceived ease of use and perceived usefulness heighten individuals' positive attitudes toward using microcomputers. Perceived ease of use and perceived usefulness also indirectly affect microcomputer attitudes through their effect on computer anxiety. The results show that higher levels of perceived ease of use and perceived usefulness result in lower levels of computer anxiety. A surprising result from the study is that while perceived ease of use is shown to directly affect the level of microcomputer usage, perceived usefulness and attitude toward using microcomputers does not. The results of the multisample analysis confirm that the research model fits the stacked model and that the stacked model is a significantly better fit if specific parameters are allowed to vary between the two human-computer interface user groups. In general, these results confirm that an interaction exists between the type of human-computer interface (the variable providing the grouping) and the other variables in the model The results show a clear difference between the two groups in the way in which perceived ease of use and perceived usefulness affect microcomputer attitude. In the case of users of command-line interfaces, these variables appear to affect microcomputer attitude via an intervening variable, computer anxiety, whereas in the graphical interface user group the effect occurs directly. Related to this, the results show that perceived ease of use and perceived usefulness have a significant direct effect on computer anxiety in command-line interface users, but no effect at all for graphical interface users. Of the two exogenous variables only perceived ease of use, and that in the case of the command-line interface users, has a direct significant effect on extent of use of microcomputers. In summary, the research has contributed to the development of a theory of individual adjustment to information technology in the workplace. It identifies certain perceptions, anxieties and attitudes about microcomputers and shows how they may affect work outcomes such as job satisfaction and job performance. It also shows that microcomputer-interface types have a differential effect on some of the hypothesised relationships represented in the general model. Future replication studies could sample a broader cross-section of the microcomputer user community. Finally, the results should help Big Six accounting firms to maximise the benefits of microcomputer use by making them aware of how working with microcomputers affects job satisfaction and job performance.

Enhancing hotel managers’ organisational commitment : an investigation of the impact of structure, needfor achievement and participative budgeting

This study investigates the role of decentralised structure and managers’ need for achievement as antecedents of participative budgeting, and the impact of the concurrent relationships of all three preceding variables on organisational commitment. Ninety-one managers from the Australian hotel industry participated in the study and data were analysed using path analysis. Direct and positive relationships were found between the two antecedent variables: decentralised structure and managers’ need for achievement, and participative budgeting. Participative budgeting, in turn, was found to have a direct and positive relationship with organisational commitment. The results of the study have implications for the design of effective management control processes and for human resource management of hospitality organisations.

Attachment as a predictor of leadership and follower outcomes

Research has suggested that effective leadership, specifically the utilisation of transformational leadership behaviours, is heavily entrenched in a leader’s interpersonal skills. However, few studies have investigated the interpersonal factors that drive appropriate use of transformational and transactional leadership in leader-follower settings. Attachment theory provides a robust framework in which to chart the developmental precursors of effective leadership that underpin positive leader-follower relationships and potential organisational outcomes. In this study, 46 manager-non manager dyads recruited from a Victorian education institution, a national telecommunications company and a Victorian real-estate business (managers – Mean age = 48.5 years, SD = 7.78, non-managers – Mean age 43.92 years, SD = 8.72) took part in an online questionnaire. Participants completed measures of attachment, leadership behaviour and organisational citizenship behaviour. Path analysis revealed that manager’s attachment style significantly predicted follower ratings of transformational and transactional leadership behaviours. Additionally, follower ratings of leadership were associated with organisational citizenship behaviour. Thus, it is concluded that attachment theory provides a valid framework in which to understand follower perceptions of leadership behaviour and subsequent organisational outcomes. These findings are discussed within the context of attachment theory and the leadership literature.

Gaming maching addiction : the role of avoidance, accessibility and social support

Commonality in etiology and clinical expression plus high comorbidity between pathological gambling and substance use disorders suggest common underlying motives. It is important to understand common motivators and differentiating factors. An overarching framework of addiction was used to examine predictors of problem gambling in current electronic gaming machine (EGM) gamblers. Path analysis was used to examine the relationships between antecedent factors (stressors, coping habits, social support), gambling motivations (avoidance, accessibility, social) and gambling behavior. Three hundred and forty seven (229 females: M = 29.20 years, SD = 14.93; 118 males: M = 29.64 years, SD = 12.49) people participated. Consistent with stress, coping and addiction theory, situational life stressors and general avoidance coping were positively related to avoidance-motivated gambling. In turn, avoidance-motivated gambling was positively related to EGM gambling frequency and problems. Consistent with exposure theory, life stressors were positively related to accessibility-motivated gambling, and accessibility-motivated gambling was positively related to EGM gambling frequency and gambling problems. These findings are consistent with other addiction research and suggest avoidance-motivated gambling is part of a more generalized pattern of avoidance coping with relative accessibility to EGM gambling explaining its choice as a method of avoidance. Findings also showed social support acted as a direct protective factor in relation to gambling frequency and problems and indirectly via avoidance and accessibility gambling motivations. Finally, life stressors were positively related to socially motivated gambling but this motivation was not related to either social support or gambling behavior suggesting it has little direct influence on gambling problems.

Predicting landscape-genetic consequences of habitat loss, fragmentation and mobility for multiple species of woodland birds

Inference concerning the impact of habitat fragmentation on dispersal and gene flow is a key theme in landscape genetics. Recently, the ability of established approaches to identify reliably the differential effects of landscape structure (e.g. land-cover composition, remnant vegetation configuration and extent) on the mobility of organisms has been questioned. More explicit methods of predicting and testing for such effects must move beyond post hoc explanations for single landscapes and species. Here, we document a process for making a priori predictions, using existing spatial and ecological data and expert opinion, of the effects of landscape structure on genetic structure of multiple species across replicated landscape blocks. We compare the results of two common methods for estimating the influence of landscape structure on effective distance: least-cost path analysis and isolation-by-resistance. We present a series of alternative models of genetic connectivity in the study area, represented by different landscape resistance surfaces for calculating effective distance, and identify appropriate null models. The process is applied to ten species of sympatric woodland-dependant birds. For each species, we rank a priori the expectation of fit of genetic response to the models according to the expected response of birds to loss of structural connectivity and landscape-scale tree-cover. These rankings (our hypotheses) are presented for testing with empirical genetic data in a subsequent contribution. We propose that this replicated landscape, multi-species approach offers a robust method for identifying the likely effects of landscape fragmentation on dispersal.