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PubMed2002

Managing during times of uncertainty. Part II--Long-term strategies.

It could be argued that uncertainty is currently part and parcel of most businesses. The degree of uncertainty may vary at times, but many occupational health nurse managers learn to live with a degree of insecurity in their jobs, and with the service they manage. The strategies discussed in this column can help occupational health nurses manage their departments more efficiently under the best of circumstances, and help identify strategies to use in times of increased uncertainty.

Adaptation, Psychological↗
PubMed2003

Certainties and uncertainties of land cover statistics in China.

Vegetation or land cover maps have been made directly or indirectly available for the entire territory of China. The certainties and uncertainties of land cover statistics were analyzed by comparing three data sources: China's Vegetation Map, IGPB DISCover, and University of Maryland Product. Great similarities in the statistics of 7 aggregated land cover types were found among the three data sources,particularly between the two global land cover maps. The per-pixel agreement between any 2 of 3 maps was between 38.0%-51.4%; the per-pixel agreement among all three maps was only 27.1%. Certainties were found in regions where vegetation types are typical and human land use practice is relatively homogenous; the uncertainties occurred to either vegetation transition zones or regions where land cover types and land use practice are relatively diversified. Systematic and multidisciplinary efforts are necessary to promote accurate mapping of nationwide land cover types in China. Intensive efforts should be made in regions where uncertainties of land cover information are found.

China↗
PubMed1992

Expert systems in histopathology. IV. The management of uncertainty.

Expert systems deal with data that are categorical and conceptual, that represent elements of fuzzy sets and that often, by themselves, do not allow an unequivocal decision. The management of uncertainty in expert systems thus becomes a crucial issue. It involves defining measures of uncertainty and procedures for combining accumulating evidence in a manner that properly considers the dependence structure of diagnostic clues. Probability theory offers valuable procedures for uncertainty assessment; however, their practical application in the domain of quantitative histopathology and histopathologic diagnosis can be problematic.

Diagnosis, Computer-Assisted↗
PubMed2004

[Uncertainty in-statistical-monitor for ICP-AES measurement system by using moving range pooled].

This paper describes how to estimate the uncertainty when Fe in metallic silicon is determined by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometry). The technique of the averaged moving range (MR) pooled in-statistical-dynamic-monitor is proposed. The study suggests that the uncertainty contribution of ICP-AES measurement system is, by using this technique, a combination of quality control (QC) and linear fit. This conclusion maximized the combination of the effects on various variances, refrained from the complicated relativity, and favored the uncertainty evaluation for ICP-AES measurement system.

English Abstract↗
PubMedDate not supplied

AIDS family caregiving: transitions through uncertainty.

The purpose of this study was to describe the experience of AIDS family caregiving. Grounded theory provided the methodological basis for qualitative data generation and analysis. Extensive interviews were conducted with 53 individuals (lovers, spouses, parents of either adults or children with AIDS, siblings, and friends) who were taking care of a person with AIDS at home. Relevant features of the social context of AIDS family caregiving were explored. Findings revealed the basic social psychological problem of Uncertainty, a core category of Transitions Through Uncertainty, and five subcategories: Managing and Being Managed by the Illness; Living With Loss and Dying; Renegotiating the Relationship; Going Public; and Containing the Spread of HIV. Stages and strategies of each subcategory detailed individuals' responses to the challenges of AIDS family caregiving and elaborated the day-to-day experiences. Uncertainty as a critical challenge for individuals and families facing life-threatening illness is discussed in light of recent research.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Adaptation to multiple sclerosis: the role of social support, functional disability, and perceived uncertainty.

This study was designed to test a path model depicting the relationships among social support, functional disability, perceived uncertainty, and psychosocial adaptation in 38 men and 80 women with multiple sclerosis, a chronic, unpredictable disease. Results from the regression analyses indicated that 35% of the variance in depression and 33% of the variance in purpose-in-life, respectively, were explained by age, sex, social status, and the perceived supportiveness and unsupportiveness of social network interactions. The path analyses showed that the perceived supportiveness of interactions was directly related to purpose-in-life but not to depression; both the direct path between the perceived unsupportiveness of interactions and adaptation and the indirect one through perceived uncertainty were related to depression and to purpose-in-life; and functional disability had a direct effect on adaptation, but the indirect path through perceived uncertainty was not corroborated.

Adaptation, Psychological↗
PubMed1990

Uncertainty, information needs, and coping effectiveness of renal families.

The purposes of this exploratory descriptive study were to assess renal families' informational needs, uncertainty level, and perceived coping effectiveness in relation to living with chronic kidney failure and hemodialysis therapy. The significant findings were: (a) knowledge was negatively correlated to uncertainty; (b) level of education was positively correlated only with coping effectiveness; and (c) neither knowledge nor uncertainty were significantly correlated to coping effectiveness.

Adaptation, Psychological↗
PubMed1989

Uncertainty and the lives of persons with AIDS.

This article uses interview data to explore how 23 gay and bisexual men who had AIDS were affected by and managed uncertainty. Before diagnosis these individuals had to find ways to cope with uncertainty about their risk of contracting AIDS and about their initial symptoms. After diagnosis they had to find answers to their questions about why they contracted this disease, whether they would be able to function in the short run, whether their illness would kill them, and whether they would be allowed to live and (if death was unavoidable) to die with dignity. The data suggest that persons with AIDS respond to the uncertainties of their illness by attempting to assert as much control as possible over their lives, through such divergent strategies as seeking and avoiding knowledge about their illness.

Acquired Immunodeficiency Syndrome↗
PubMed1988

[Dose uncertainties in irradiation of bladder cancer with the Nd: YAG laser beam].

By in vitro investigations with the laser set medilas 2 YAG (MBB) possible dosage insecurities were demonstrated in the radiation of urinary bladder cancers using Nd-YAG-laser light. While the endoscopic distance of e.g. 3 +/- 1 mm is accompanied by a relatively low dosage uncertainty of +/- 23%, the thermic formation of gas bubbles on the endoscopic end area, which is immersed in flush fluid, may be cause a dosage uncertainty of 80%. Help is possible by slipp off the endoscope area on the bladder wall. Uncertainties because of different tissue absorption of radiation are not taken into account.

Cystoscopy↗
PubMedDate not supplied

Parents' perception of uncertainty concerning their hospitalized child.

The Parent Perception of Uncertainty Scale (PPUS) was developed to measure a perceptual variable believed to influence parents' response to their child's illness and hospitalization. This 31-item Likert-format scale was modified from the original form of the uncertainty scale. The PPUS was composed of four factors measuring the four dimensions of uncertainty consistent with theoretical predictions. Initial testing for reliability found the coefficient alphas and thetas to be adequate for a new scale. Validity testing with theoretically relevant external variables was partially supportive of predictions. Questions remain concerning the adequacy of Factor II. Further testing of the scale is indicated.

Adaptation, Psychological↗
PubMed1982

Managing uncertainty in family practice.

Because patients present in the early stages of undifferentiated problems, the family physician often faces uncertainty, especially in diagnosis and management. The physician's uncertainty may be unacceptable to the patient and may lead to inappropriate use of diagnostic procedures. The problem is intensified by the physician's hospital training, which emphasizes mastery of available knowledge and decision-making based on certainty. Strategies by which a physician may manage uncertainty include (a) a more open doctor-patient relationship, (b) understanding the patient's reason for attending the office, (c) a thorough assessment of the problem, (d) a commitment to reassessment and (e) appropriate consultation.

Decision Making↗
PubMed1981

Intention and uncertainty at later stages of childbearing: the United States 1965 and 1970.

While births may be dichotomous, fertility intentions are not inherently so. Intentions are predictions about the future and, as such, are couched in considerable uncertainty. Ignoring this uncertainty hides much of what could be learned from data on fertility intentions. This paper presents a model which allows analysis of the full range of intentions. This paper presents a model which allows analysis of the full range of intentions. After selecting a sample of women in the later stage of childbearing (e.g., those who intend fewer than two additional children) from the 1965 and 1970 National Fertility Studies, it is shown that: (1) substantial portions of women at this stage of the reproductive life cycle were indeed uncertain of their parity-specific intention; (2) this certainty, like more firm intentions, varies by age and parity as the model predicts; and (3) there were significant shifts in the level of certainty between 1965 and 1970. Specifically, while intentions for third, fourth, and fifth births declined, more women "didn't know" if they intended to have another child or not. Among those not intending another child, more seemed uncertain of this intention in 1970 than did comparable women in 1965. In contrast, those intending another child seemed more certain. These changes in intention and uncertainty indicate that the observed decline in intended parity was tentative. Post-1970 evidence suggests that this tentative decline has become an equivocal one.

Adolescent↗
PubMed1995

[Health care economics, uncertainty and physician-induced demand].

The health care market is a very particular one that is mainly characterized by the absence of information and transparency at every level, particularly between the physician-supplier and the patient-consumer. On this market it is up to the physician to evaluate and define the patient's needs and to decide which are the most effective goods for the patient. The determinants of medical prescription are not only related to the health status of the patient, but also to the payment system (fee for services, salary), to physician density, professional uncertainty, the role and status of the physician in his profession, the legal framework which rules the medical profession, and also the information level of the patient. Agency relationship and professional uncertainty are the most relevant determinants of supplier-induced demand. Professional uncertainty inherent in the practice of a stochastic art such as medicine will "always" give an ethical justification for supplier-induced demand or for the pursuit of "maximal" and/or "defensive" care when market competition is perceived by the physician as a threat to his/her income or employment. Time is ripe for consumers and physicians empowerment in the aim to promote better self-management of health and more thoughtful access to care (for consumers) and more evidences based medicine for physicians.

Economic Competition↗
PubMed1995

Prostate Cancer Intervention Versus Observation Trial: economic analysis in study design and conditions of uncertainty.

The Prostate Cancer Intervention Versus Observation Trial (PIVOT) compares radical prostatectomy with palliative expectant management of patients with clinically localized prostate disease. As with all clinical trials, several of the assumptions underlying PIVOT are characterized by uncertainty. Economic analysis has the potential to clarify some of these important issues, thereby guiding study design and interpretation and enhancing the clinical usefulness of the findings. One important uncertainty about the trial relates to the true clinical state of potentially eligible patients. While clinical examination is an insensitive method by which to stage prostate cancer, several diagnostic tests, such as bone scanning and magnetic resonance imaging with rectal coil, are more accurate but more expensive. Another issue is whether to start the trial with the screening of patients or at the time of prostate cancer diagnosis. Economic analysis can assess these trade-offs between study cost and validity. A second potential role for health economics is in dealing with the considerable uncertainty surrounding the study's findings and conclusions and their interpretation. While the stated primary outcome of the trial is survival, a multidimensional outcome (particularly one that incorporates factors of survival, quality of life, and cost) is likely to be more clinically relevant in the prostate cancer population, given the only modest improvements in survival hypothesized for radical prostatectomy. To develop such a measure, quantitative assessment of patient preferences is required, in addition to the measures currently included in the study. Assessment of costs of care are important, given the large and growing size of the study's target population.(ABSTRACT TRUNCATED AT 250 WORDS)

Cost-Benefit Analysis↗
PubMed1995

[Systems analysis of behavior in conditions of environmental uncertainty].

The paper deals with the organizational features of the functional behavior system under environmental uncertainty conditions (probability training processes, formation of a conditioned reflex at a low intensity of a signal stimulus), as well as with the probability pattern of reinforcement. It shows that the experimental findings are not always in full conformity with the classical behavior act model developed by P. K. Anokhin. The main difficulty is associated with the fact that the above model in its systems content considers a behavioral act merely alone whereas while teaching under great uncertainty conditions, correction of the programme of actions is possible only when many search reactions are simultaneously analyzed. While making a systems analysis of behavioral performance, it is proposed to use a concept of probability decision to alter the programme of action, as well as an idea of memory buffer (results of search reactions). The proposed approach allows one to describe various training conditions, and it operates as the Anokhin model in a specific case. The organizational features of the functional system of behavior under great uncertainty conditions should be taken into account while specifying the informational mechanism responsible for systems quantization of behavior. The above mechanism of the comprehensive evaluation of the positive and negative results of the performed pattern of behavioral acts can be used to explain the discreteness of an action in the programme alteration process when the same quantum of behavior is implemented.

Behavior↗
PubMed1996

Development and Psychometric evaluation of an instrument to measure staff nurses' perception of uncertainty in the hospital environment.

Perceived environmental uncertainty is an individual response to stimuli in the internal and/or external environment. The measurement of uncertainty in the health care environment is important in order to characterize the impact of this phenomenon on nursing practice. This study describes the development, pilot testing, and initial psychometric evaluation of the Perceived Environmental. Uncertainty in Hospitals Scale (PEU-H) in a sample of 95 hospital staff registered nurses. Principal components analysis of the PEU-H was conducted and indicated that the factor structure represented one factor that explained 37.3% of the variance. Internal consistency reliability using Cronbach's alpha was .83, which is acceptable for a scale in the early stages of development.

Adult↗
PubMed1995

Uncertainty and decisions in medical informatics.

This paper presents a tutorial introduction to the handling of uncertainty and decision-making in medical reasoning systems. It focuses on the central role of uncertainty in all of medicine and identifies the major themes that arise in research papers. It then reviews simple Bayesian formulations of the problem and pursues the generalization to the Bayesian network methods that are popular today. Decision making is presented from the decision analysis viewpoint, with brief mention of recently-developed methods. The paper concludes with review of more abstract characterization of uncertainty, and anticipates the growing importance of analytic and "data mining" techniques as growing amounts of clinical data become widely available.

Bayes Theorem↗
PubMed1998

Submicrovolt flicker electroretinogram: cycle-by-cycle recording of multiple harmonics with statistical estimation of measurement uncertainty.

PURPOSE: To study cycle-by-cycle recording of small-amplitude flicker-electroretinogram (ERG) responses and analyze results with robust statistical methods to estimate the measurement uncertainty. METHODS: Flicker ERGs at 32 Hz were recorded simultaneously from both eyes of patients with retinal degeneration. The ERG was amplified under wide-band (1-1000 Hz) conditions, digitized at 6144 Hz/eye, and multiplied point for point (192 points/cycle) by sine and cosine functions within each 1/32-second flash cycle to extract coefficients for six harmonic components of a discrete Fourier transform in real time. Amplitude windowing was not used, and all data were saved for subsequent statistical processing to identify and remove large-amplitude artifacts discretely and to search for quiet recording periods that minimized small-amplitude noise. RESULTS: Plots of amplitude and phase indicated far outlying noise points that were excised from the data. The SD of sequential intervals on a time line of the sine component identified quiet periods that minimized small-amplitude noise and improved measurement consistency. The SE of the response mean provided an estimate of measurement uncertainty. CONCLUSIONS: The harmonic components of many individual responses are captured quickly (e.g., 500 responses in 15.6 seconds) for post hoc statistical analysis, using mathematical algorithms that are precisely reproducible to facilitate comparison of results from all laboratories. Graphical time lines of responses allow separation of artifact transients from gaussian noise for elimination of noisy periods without disturbing the stored information. Statistical estimates of measurement uncertainty are determined on-line to allow immediate feedback during the recording session. Amplitude-phase plots of the multiple harmonic components, along with reconstructed analog waveforms, provide results in a readily assimilated manner for comparison of all testing sessions.

Electroretinography↗