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PubMedDate not supplied

Supervisors' use of social power with graduate supervisees in speech-language pathology.

This investigation discusses social power as an identifiable and measurable aspect of the supervisory process in speech-language pathology (SLP). This study examined the use of French and Raven's (1959) types of social power by 61 clinical supervisors with their 69 beginning and 69 advanced graduate supervisees from 14 university programs. Both supervisors' and supervisees' perceptions of supervisors' use of expert, referent, coercive, legitimate, and reward power were obtained with modified versions of the Rahim Leader Power Inventory (RLPI) (Rahim, 1988). The supervisors' perceptions of their use of the five types of social power with beginning supervisees were not significantly different from the beginning supervisees' perceptions. By contrast, the study yielded discrepant perceptions of supervisors' use of social power with advanced supervisees. Further, supervisors reported differential use of power with supervisees with different amounts of clinical experience. Yet, the perceptions of beginning and advanced supervisees did not differ relative to supervisors' use of any of the five types of social power. These findings can sensitize clinical supervisors to the sources of social power inherent in their practice.

Adult↗

PubMed2001

The impact of a hydroelectric power plant on the sediment load in downstream water bodies, Svartisen, northern Norway.

When the Svartisen hydroelectric power plant was put into operation, extensive sediment pollution was observed in the downstream fjord area. This paper discusses the impact of the power plant and the contribution from various sources of sediment. Computation of the sediment load was based on samples collected one to four times per day. Grain size distribution analyses of suspended sediments were carried out and used as input in a routing model to study the movement of sediments through the system. Suspended sediment delivered to the fjord before the power station was constructed was measured as 8360 metric tons as an annual mean for a 12-year period. During the years 1995-1996 when the power plant was operating, the total suspended load through the power station was measured as 32609 and 30254 metric tons, respectively. Grain size distribution analyses indicate a major change in the composition of the sediments from 9% clay before the power plant was operative to 50-60% clay afterwards. This change, together with the increase in sediment load, is believed to be one of the main causes of the drastic reduction in secchi depths in the fjord. The effect of the suspended sediment load on the fjord water turbidity was evaluated by co-plotting secchi depth and power station water discharge. Measurements during 1995 and 1996 showed that at the innermost of these locations the water failed to attain the minimum requirement of 2 m secchi depth. In later years secchi depths were above the specified level. In 1997 and 1998 the conditions improved. At the more distal locality, the conditions were acceptable with only a few exceptions. A routing model was applied to data acquired at a location 2 km from the power station in order to calculate the contributions from various sediment sources. This model indicated that the contribution from reservoir bed erosion dominated in 1994 but decreased significantly in 1995. Future operation of the power station will mostly take place with a high water level in the reservoir and is likely to result in acceptable water quality in the fjord. However, during periods of low drawdown, sediment pollution may again become a problem.

Environmental Monitoring↗

PubMed2001

Relationship orientation as a moderator of the effects of social power.

This research examined the hypothesis that the concept of power is mentally associated with different goals for individuals with a communal versus an exchange relationship orientation (M. S. Clark & J. Mills, 1979). It was predicted that communals associate power with social-responsibility goals, whereas exchangers link power with self-interest goals. Thus, when power is activated, distinct goals should be ignited for communals and exchangers. Power was primed unobtrusively using semantic cues in Study 1 and using naturally occurring, environmental cues in Studies 2 and 3. Across studies, power-primed communals responded in socially responsible ways, whereas power-primed exchangers acted more in line with their self-interests. These power-goal effects occurred nonconsciously. Overall, the data support taking a Person x Situation approach--one that allows for moderators such as relationship orientation--to understand power's positive and negative effects.

Altruism↗

PubMed2003

From power to action.

Three experiments investigated the hypothesis that power increases an action orientation in the power holder, even in contexts where power is not directly experienced. In Experiment 1, participants who possessed structural power in a group task were more likely to take a card in a simulated game of blackjack than those who lacked power. In Experiment 2, participants primed with high power were more likely to act against an annoying stimulus (a fan) in the environment, suggesting that the experience of power leads to the performance of goal-directed behavior. In Experiment 3, priming high power led to action in a social dilemma regardless of whether that action had prosocial or antisocial consequences. The effects of priming power are discussed in relation to the broader literature on conceptual and mind-set priming.

Adult↗

PubMed1997

Adherence: a matter of self-efficacy and power.

This paper examines the relationship between self-efficacy and social power (expert and referent) and how the application of this relationship, leads to client adherence and compliance. Referent power is defined, including methods that health care professionals may use to develop and apply referent power. Expert power is defined and addressed in the context of referent power, self-esteem and self-efficacy as a means of promoting adherence. Self-efficacy as a concept is defined and explored in the context of social power. The relationships between self-efficacy and social power (expert and referent) are shown as important determinants of adherence and compliance. The theory of the application of referent and expert power in relationship with self-efficacy has been compared with an effective programme, yielding high compliance, at Western Psychiatric Institute and Clinic, showing the theory's relevance and applicability in determining compliance. Explored are the reasons for non-compliance in the elderly population and how the theory model can remedy these detriments for compliance. The empowerment of elderly patients through the application of this theory to medication compliance is examined. The determination of adherence and compliance is shown by the application of the relationship between self-efficacy and both expert and referent power.

Aged↗

PubMed2005

Agents of care and agents of the state: bio-power and nursing practice.

AIM: This paper presents a conceptual analysis of the concept of bio-power in the context of nursing, including a critique of the widespread rhetoric that nursing is deprived of power and consequently is an apolitical agency. BACKGROUND: Traditionally, power tends to be defined in terms of repression, interdiction and punishment. On the contrary, work by Michel Foucault with regard to bio-power brings into evidence the productive and positive nature of power at the heart of society. Despite being often used by various academic and professional disciplines, the concept of bio-power is rarely cited in nursing. FINDINGS: Nursing as a profession is at the heart of bio-power in that nurses lie at the crossroads between the anatomo-political and bio-political ranges of power over life. They therefore contribute to social regulation through a vast array of diverse political technologies. Nurses are at the flexing point of the state's requirements and of individual and collective aspirations. They occupy a strategic position that allows them to act as instruments of governmentality. Consequently, nurses constitute a fully-fledged political entity making use of disciplinary technologies and responding to state ideologies. CONCLUSION: The concept of bio-power offers a rich theoretical perspective for nursing, as it questions the definition of nursing care as neutral and mainly provided according to patients' best interests.

Authoritarianism↗

PubMed2004

Leadership behaviours that foster nursing group power.

Today's health care environment presents many challenges to nursing groups as they seek to achieve their goals. All resources must be recognized and effectively utilized. Power, defined as the capacity to achieve goals (Sieloff 1995), is a valuable resource that can assist nursing groups in the achievement of their goals. The leader of a nursing group can make a significant difference in a group's ability to actualize their power capacity. The purpose of this article is to identify and discuss the use of a tool (Sieloff-King Assessment of Group Power within Organizations) to identify the nurse leader/group power variables that can be used to improve a nursing group's power as a resource in the achievement of its goals. Using behaviours related to a Nurse Leader's Power Competency and Power Perspective variables, identified in the Theory of Group Power within Organizations (Sieloff 1999), a nurse leader can foster a nursing group's power.

Attitude of Health Personnel↗

PubMed1985

Power in client and nurse-therapist relationships.

Social theory provided the perspective for this exploration of power as it relates to the nurse/client relationship. As the authors agree with Smith and Vetter (1982) that interactions are a legitimate basis for understanding behavior, we, have, therefore, presented actual nurse/client relationships as empirical cases to examine and to apply theory. These six vignettes provide examples of various responses of patients and therapists to power in therapeutic relationships. Although each situation differs in some respects, there are similarities regarding power as a phenomenon. Dependence and sanctions, the objective features of power, are present. On analyzing the audiotapes and process notes from the individual therapy of clients and nurses who were beginning therapists enrolled in a graduate psychiatric nursing program, it becomes clear that the therapists got involved in power struggles with their clients or used exploitive power when they, themselves, felt vulnerable or angry because they perceived their expert power to be threatened. It also becomes clear that the nurse-therapists were not always accustomed to, or comfortable with, an autonomous role. They, therefore, sometimes failed to use their legitimate powers. However, once they reviewed their interactions within a conceptual framework of power, and discussed these issues with clinical and academic supervisors, they could examine causes, characteristics, and potential changes in their reactions to their clients.

Adult↗

PubMed2003

Relations between high and low power groups: the importance of legitimacy.

Using a social identity perspective, two experiments examined the effects of power and the legitimacy of power differentials on intergroup bias. In Experiment 1, 125 math-science students were led to believe that they had high or low representation in a university decision-making body relative to social-science students and that this power position was either legitimate or illegitimate. Power did not have an independent effect on bias; rather, members of both high and low power groups showed more bias when the power hierarchy was illegitimate than when it was legitimate. This effect was replicated in Experiment 2 (N = 105). In addition, Experiment 2 showed that groups located within an unfair power hierarchy expected the superordinate power body to be more discriminatory than did those who had legitimately high or low power. The results are discussed in terms of their implications for group relations.

Adult↗

PubMed1997

The normative constitution of professional power.

This article concerns the manner in which we think and talk about power in health care policy and regulation, and the political and social practices allied with that discourse. I assert that in health care policy and practice we speak of and live within the era of countervailing power. In this language and practice power is a force exercised by one actor to enforce its will against another actor against whom power is exerted. I contend that this language inculcates an individual and social passivity in which citizens rely upon various types of representatives to constitute health care for them in a manner in which they do not and cannot participate. However, this language of power and the political and social practice with which it is associated is merely a contingent, historical product. I claim that an alternative discourse of power is possible, in which power consists of the social interactions in which all of us mutually participate but no one of us can control. Power in this sense is participatory by nature, and because no one is in control, it makes no sense to relegate tasks to specialized, nonparticipatory domains. This alternative discourse of power, therefore, might call forth participatory practices in health care and a concomitant diminution of specialization and expansion of the public sphere. The result would be to blur the lines separating politics from everyday interaction, politics from economy, professionals from patients, and insurers from insureds. Participation would mean much more than casting a vote or writing a check but would also include the mutual sharing of time and energy in the tasks that need to be done: long-term and short-term care, practices of prevention, caring for the chronically ill, and monitoring bureaucratic and professional activities.

Budgets↗

PubMed2005

An experimental examination of social contexts and the use of power in a Chinese sample.

Researchers have considered power as a largely corrupting force in organizations. In the present experiment, the authors used the theory of cooperation and competition to investigate the effects of social context on power use in a sample of Chinese participants. The present results support the reasoning that high power compared to low power provides the capacity to assist employees and that cooperative, but not competitive, goals facilitate the motivation of managers to use their power to support employees and to develop managerial conclusions that employees are capable and appreciative. These results suggest limitations to traditional organizational power theories that assume a competitive context between the powerful and those subject to power. Cooperative goals appear to be an important basis for developing the positive face of power in organizations in China and perhaps in other cultures as well.

Adult↗

PubMed1994

Power orientation: a study of female nurse and non-nurse managers.

Researchers studied the power orientations of female managers as related to career choice, education level, age, and years as a manager. The questionnaire includes six orientations to power: 1) power as good; 2) power as resource dependency; 3) power as instinctive drive; 4) power as political; 5) power as charisma; and 6) power as control and autonomy. Discerning power may explain how one perceives the managerial position.

Administrative Personnel↗

PubMedDate not supplied

Powered instrumentation for nasal bone reduction: advantages and indications.

OBJECTIVE: To evaluate power-assisted bone removal in cosmetic rhinoplasty. DESIGN: Nonrandomized, nonblinded, retrospective evaluation of consecutive case series. SETTING: Academic facial plastic surgery practice. INTERVENTIONS: Power-assisted bone removal in 105 consecutive rhinoplasties requiring nasal bone reduction. MAIN OUTCOME MEASURES: Subjective evaluation by patient and surgeon. RESULTS: Of the 105 patients undergoing power-assisted bone removal, 102 obtained satisfactory refinement of the nasal dorsum after 1 operation. Three patients required surgical revision of the nasal dorsum following power-assisted bony hump reduction. Of these, 2 required surgical revision for delayed bone regrowth, while the remaining patient required surgical treatment of a persistent bony hump. Ultimately, all 105 patients achieved satisfactory surgical results. No other surgical complications were observed. CONCLUSIONS: Power-assisted bone removal is a useful adjunct for bone removal in cosmetic rhinoplasty. This study confirms the previously reported advantages of powered instrumentation for patients with small bony humps or modest bony asymmetries. Moreover, because powered instrumentation is comparatively atraumatic, it may be preferable for use in nasal bones previously weakened by trauma, aging, or prior nasal surgery. Finally, because the powered nasal rasp permits rounding of the bone edges, the characteristic widening associated with flat hump reduction is reduced, and the need for aggressive sidewall infracture is diminished. Complications associated with power-assisted bone removal were rare.

Adult↗

PubMed2000

Gray-scale and power doppler sonographic appearances of acute inflammatory diseases of the scrotum.

PURPOSE: We describe the spectrum of gray-scale and power Doppler sonographic appearances in inflammatory scrotal diseases. METHODS: Twenty-five patients ranging in age from 3 to 69 years underwent gray-scale and power Doppler sonography with multifrequency transducers of 7-9 MHz or 10-13 MHz. In addition, color Doppler and power Doppler findings were compared in 7 cases. RESULTS: In all 5 prepubertal patients, power Doppler imaging demonstrated hyperemia associated with epididymitis and, in some cases, orchitis. Among the 20 pubertal and adult patients, power Doppler imaging revealed increased vascularity associated with spermatic cord involvement, epididymitis, orchiepididymitis, or orchitis. Enlargement and heterogeneity of the epididymis and/or testis were seen in 11 patients, with vas efferens ectasia in 3 patients. Abscess formation and testicular infarction were easily depicted by power Doppler imaging. In 5 cases total, hyperemia was the only sonographic finding of inflammation. In the comparison between color and power Doppler imaging, a subjective increase in the number and length of vessels was seen with power Doppler imaging. CONCLUSIONS: Power Doppler imaging is an easy and fast Doppler modality for evaluating inflammatory conditions of the scrotum and proved especially useful in cases with no gray-scale sonographic anomalies, in prepubertal patients, and in patients with abscesses or ischemic lesions.

Acute Disease↗

PubMed1995

Residential exposure to magnetic fields generated by 110-400 kV power lines in Finland.

In a specific case, the magnetic field generated in a building by a nearby power line is usually easy to calculate, although the accuracy of these calculations is sensitive to the quality of source information. To be able to study public health dimensions of magnetic field exposure (e.g., risk of cancer), it is necessary to evaluate the size and exposure of the population at risk. Relatively little quantitative information on public exposure to power-frequency magnetic fields of high-voltage power lines is available. This report describes residential exposure to magnetic fields from 110 kV, 220 kV, and 400 kV power lines in Finland at the national level, including 90% of the total line length in 1989. A geographical information system (GIS) was used to identify the buildings located near the power lines. After determining the distances between the lines and the buildings, historical data on load currents of these lines were used to calculate the magnetic fields. The residential magnetic field histories were then linked to the residents by means of a computerized central population register. The data obtained on personal exposure have also been utilized in a nationwide epidemiological study on magnetic field exposure of power lines and risk of cancer. The methods of exposure assessment and results of the number of buildings near 110 kV, 220 kV, and 400 kV power lines, their average annual magnetic fields, and personal exposure to magnetic fields from these lines are described. We found that 15,600 residents lived in an average residential magnetic field > or = 0.1 microT caused by power lines in 1989. The number of these residents increased fivefold during 1970-1989. We estimated that 0.3% of the population was exposed in their residences to an annual average magnetic flux density from 110 kV, 220 kV, and 400 kV power lines higher than 0.1 microT, the level that the background magnetic flux density in general does not exceed in Finnish homes. Thus, the problem of magnetic field exposure generated by high-voltage lines concerns only a relatively small fraction of the total population in Finland. However, the size and exposure of the population at risk remain somewhat arbitrary in practical multisource situations, as the biological interaction mechanism, the concept of harmful dose, and, in particular, the significance of the duration of exposure are unknown.

Child↗

PubMed2005

Epidemiologic studies of adverse effects of anti-retroviral drugs: how well is statistical power reported.

PURPOSE: To determine whether there is a difference in average statistical power between pharmacoepidemiologic studies of anti-retroviral adverse drug effects (ADEs) sponsored by for-profit versus non-profit organizations. METHODS: We studied all published pharmacoepidemiologic studies of ADEs associated with the 15 anti-retroviral drugs approved through the end of 1999. A priori, the primary outcome was the power of each study to detect a clinically important difference in the risk for an adverse effect among patients exposed to the study drug(s). We could not evaluate this outcome because of the infrequent reporting of power calculations. We instead report the distribution of studies across a 5-tiered measure of adequacy of reporting of statistical power, as well as the sponsorship of these studies. RESULTS: Of 48 studies meeting our inclusion criteria, only 1 (2%) reported either a completed, a priori power calculation or sufficient details for readers to calculate the power to detect a pre-defined, clinically important effect. Thirty-five studies (73%) reported the minimum information required for sophisticated readers to determine the power to detect an event rate of interest to them; 6 additional studies (13%) reported confidence intervals around at least one summary effect measure and 6 (13%) provided no indication of power or uncertainty. Of the 41 studies for which sponsorship was determined, only 3 (7%) were sponsored by for-profit organizations. CONCLUSIONS: The poor reporting of statistical power in this sample suggests a need for guidelines to improve the reporting of pharmacoepidemiologic studies of ADEs. Future research is needed to determine whether the observed paucity of industry-sponsored observational studies of anti-retroviral ADEs extends to other clinical areas, and if so, to identify the causes of this phenomenon.

Adverse Drug Reaction Reporting Systems↗

PubMedDate not supplied

Some power considerations when deciding to use transformations.

Conventional wisdom suggests that for small data sets having substantial skew, one should attempt to determine the correct distributional form, if possible, and apply statistical methods appropriate for that distribution. Transformations such as the log or square root are often used. If an appropriate distributional form cannot be determined, a distribution-free procedure such as a rank transformation or a randomization test procedure can be used. To better appreciate the effect of such alternatives on both the type I error and power of detecting differences between treatment groups, simulation studies were conducted for responses having specific gamma G(r, theta) and log-normal ln(M, V) distributions. The gamma and log-normal distributions were selected so that they had the same first two moments. A simple two group design was assumed. The reference group always had an average disease level mu = 3.0 (mu = r theta for gamma, mu = M for log-normal), and the treatment group always had means whose reductions ranged from 0 per cent to 50 per cent. The effect of distributional type and the degree of skewness was investigated by varying the population parameter values. Six statistical test procedures were compared for the gamma distributions. All test procedures were robust relative to the type I error. The UMP test based on a ratio of sample means produced the greatest power for all combinations of n, r and RT. The power losses associated with the randomization test, the t-test on original scale, and the t-test on the square root scale were very small, (3 per cent to 6 per cent in absolute value) for n = 10 and 15, and less than 2 per cent for group sizes of 25 or more. The power loss associated with the t-test on the log scale was much larger, ranging from 5 per cent to 10 per cent smaller power than the t-test on original scale. The Wilcoxon rank test produced similar results to that of the LOG t-test for small samples. The power for the shifted LOG (X+c) test increased monotonically to the asymptotic value of the ORIG t-test. The same five test procedures based on differences in sample means were then compared for the corresponding log-normal distributions. The UMP test, that is, LOG(X), produced the highest power. There was very little power lost for the SQRT t-test. The loss in power varied between 2 per cent and 5 per cent for the RANK test.(ABSTRACT TRUNCATED AT 400 WORDS)

Clinical Trials as Topic↗

PubMed1998

Mapping voxel-based statistical power on parametric images.

Using a classic technique based on the noncentral F-distribution method for computing statistical power, we developed a general approach to the estimation of voxel-based power in functional brain image data analysis. We applied this method to PET data from a large sample (N = 40) of subjects performing the Wisconsin Card Sorting (WCST) paradigm analyzed with SPM95, produced statistical power maps for a range of samples sizes and smoothing filter widths, and examined the effects of sample size and image smoothing on the expected reliability of activation findings. At an uncorrected alpha of 0.01, a fixed filter size of 10 mm3, and a range of power thresholds, maps revealed that the power to reject the null hypothesis in brain regions implicated in the task at Ns of 5 and 10 may not be sufficient to ensure reliable replication of significant findings and so should be interpreted with caution. At sample sizes approaching 20 subjects, sufficient power was found in the right dorsolateral prefrontal cortex (BA 46/9), right and left inferior parietal lobule (BA 40), and left inferior temporal lobe (BA 37), comprising the cortical network typically observed during the WCST. Filter size needed to maximize power varied widely, but systematically, across the brain, tending to follow known neuroanatomical landmarks. Statistical power considerations in brain imaging studies are critical for controlling the rate of false negatives and assuring reliable detection of cognitive activation. The variation of filter size for maximizing power across the brain suggests that the underlying neuroanatomy of functional units is an important consideration in the a priori selection of filter size.

Algorithms↗