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PubMed2001

An exploration of the relationships between uncertainty, psychological distress and type of coping strategy among Chinese men after cardiac catheterization.

The experience of cardiac catheterization (CC) has included feelings of uncertainty, stress, fear and anxiety in many patients. However, conflicting findings from previous research have been reported. Chinese patients who undergo CC may experience psychological distress in a different way to other cultures as a result of traditional beliefs. Moreover, little research examining the impact of CC among Hong Kong Chinese has been carried out. Therefore, the aim of the study was to explore relationships between uncertainty, psychological distress and coping strategy in Chinese men after CC, using Mishel's model of uncertainty in illness as a framework. A convenience sample of 27 men hospitalized for cardiac catheterization participated in this study using a descriptive, correlational research design. Ethical approval was obtained from the Ethics Committee of the Medical Faculty at the Chinese University of Hong Kong and from the Executive Committee of the hospital. Participation was on a voluntary basis with patient confidentiality assured. Self-report questionnaires included Chinese versions of Mishel's Uncertainty in Illness Scale (MUIS), the Profile of Mood States (POMS), the State-Trait Anxiety Inventory (STAI) and the Chinese Coping Scale (CCS) for data collection. Data were analysed using the Statistical Package for Social Sciences. High mean scores for uncertainty (mean=101.4, SD=11.49) and variables measuring psychological distress (mood disturbance mean=36.6, SD=33.6, state-anxiety mean=39.1, SD=8.95, trait-anxiety mean=43.7, SD=8.1) among these participants suggest that Hong Kong Chinese men experience uncertainty and psychological distress when undergoing cardiac catheterization. Strong relationships between uncertainty and mood disturbance (r=0.57, P=0.01), trait-anxiety and mood disturbance (r=0.65, P=0.01) and state-anxiety and external coping strategies (r=0.50, P=0.05) were found. These findings suggest that relationships between uncertainty, psychological distress and external coping strategies exist in Chinese men hospitalized for cardiac catheterization. Moreover, these findings may help nurses' design culturally specific interventions for their patients.

Adaptation, Psychological↗

PubMed2001

Refinement of the concept of uncertainty.

AIMS: To analyse the conceptual maturity of uncertainty; to develop an expanded theoretical definition of uncertainty; to advance the concept using methods of concept refinement; and to analyse congruency with the conceptualization of uncertainty presented in the theory of hope, enduring, and suffering. BACKGROUND: Uncertainty is of concern in nursing as people experience complex life events surrounding health. In an earlier nursing study that linked the concepts of hope, enduring, and suffering into a single theoretical scheme, a state best described as 'uncertainty' arose. This study was undertaken to explore how this conceptualization fit with the scientific literature on uncertainty and to refine the concept. DESIGN/METHODS: Initially, a concept analysis using advanced methods described by Morse, Hupcey, Mitcham and colleagues was completed. The concept was determined to be partially mature. A theoretical definition was derived and techniques of concept refinement using the literature as data were applied. FINDINGS: The refined concept was found to be congruent with the concept of uncertainty that had emerged in the model of hope, enduring and suffering. CONCLUSIONS: Further investigation is needed to explore the extent of probabilistic reasoning and the effects of confidence and control on feelings of uncertainty and certainty.

Adaptation, Psychological↗

PubMedDate not supplied

The medical, personal, and social causes of uncertainty in HIV illness.

Uncertainty is an important part of the illness experience. Mishel elaborated a theory of uncertainty in acute illness and later expanded the framework to account for uncertainty in chronic illness. Researchers subsequently have investigated the causes and outcomes associated with the uncertainty in illness experience across a variety of medical conditions. The current study applies and extends Mishel's model within the context of HIV illness-related uncertainty. In this qualitative study, focus group methods were used to examine the nature of illness uncertainty experienced by persons living with HIV or AIDS. Findings confirm Mishel's contention that the causes of uncertainty extend beyond those of medical diagnosis, treatment, and recovery to personal and social aspects of daily life. Identified sources of uncertainty may have important mental health and quality of life implications.

Acquired Immunodeficiency Syndrome↗

PubMed2005

How much uncertainty is too much and how do we know? A case example of the assessment of ozone monitor network options.

Limited time and resources usually characterize environmental decision making at policy organizations such as the U.S. Environmental Protection Agency. In these climates, addressing uncertainty, usually considered a flaw in scientific analyses, is often avoided. However, ignoring uncertainties can result in unpleasant policy surprises. Furthermore, it is important for decisionmakers to know how defensible a chosen policy option is over other options when the uncertainties of the data are considered. The purpose of this article is to suggest an approach that is unique from other approaches in that it considers uncertainty in two specific ways-the uncertainty of stakeholder values within a particular decision context and data uncertainty in the light of the decision-contextual data-values relationship. It is the premise of this article that the interaction between data and stakeholder values is critical to how the decision options are viewed and determines the effect of data uncertainty on the relative acceptability of the decision options, making the understanding of this interaction important to decisionmakers and other stakeholders. This approach utilizes the recently developed decision analysis framework and process, multi-criteria integrated resource assessment (MIRA). This article will specifically address how MIRA can be used to help decisionmakers better understand the importance of uncertainty on the specific (i.e., decision contextual) environmental policy options that they are deliberating.

Journal Article↗

PubMed1997

Uncertainty of calibrations at the accredited dosimetry calibration laboratories.

The American Association of Physicists in Medicine, through a subcommittee (formerly Task Group 3) of the Radiation Therapy Committee, has accredited five laboratories to perform calibrations of instruments used to calibrate therapeutic radiation beams. The role of the accredited dosimetry calibration laboratories (ADCLs) is to transfer a calibration factor from an instrument calibrated by the National Institute of Standards and Technology (NIST) to a customer's instrument. It is of importance to the subcommittee, to physicists using the services of the ADCLs, and to the ADCLs themselves, to know the uncertainty of instrument calibrations. The calibration uncertainty has been analyzed by asking the laboratories to provide information about their calibration procedures. Estimates of uncertainty by two procedures were requested: Type A are uncertainties derived as the standard deviations of repeated measurements, while type B are estimates of uncertainties obtained by other methods, again expressed as standard deviations. Data have been received describing the uncertainty of each parameter involved in calibrations, including those associated with measurements of charge, exposure time, and air density, among others. These figures were combined with the uncertainty of NIST calibrations, to arrive at an overall uncertainty which is expressed at the two-standard deviation level. For cable-connected instruments in gamma-ray and x-ray beams of HVL > 1 mm Al, the figure has an upper bound of approximately 1.2%.

Biophysical Phenomena↗

PubMed2001

The influence of interaural stimulus uncertainty on binaural signal detection.

This paper investigated the influence of stimulus uncertainty in binaural detection experiments and the predictions of several binaural models for such conditions. Masked thresholds of a 500-Hz sinusoid were measured in an NrhoSpi condition for both running and frozen-noise maskers using a three interval, forced-choice (3IFC) procedure. The nominal masker correlation varied between 0.64 and 1, and the bandwidth of the masker was either 10, 100, or 1,000 Hz. The running-noise thresholds were expected to be higher than the frozen-noise thresholds because of stimulus uncertainty in the running-noise conditions. For an interaural correlation close to +1, no difference between frozen-noise and running-noise thresholds was expected for all values of the masker bandwidth. These expectations were supported by the experimental data: for interaural correlations less than 1.0, substantial differences between frozen and running-noise conditions were observed for bandwidths of 10 and 100 Hz. Two additional conditions were tested to further investigate the influence of stimulus uncertainty. In the first condition a different masker sample was chosen on each trial, but the correlation of the masker was forced to a fixed value. In the second condition one of two independent frozen-noise maskers was randomly chosen on each trial. Results from these experiments emphasized the influence of stimulus uncertainty in binaural detection tasks: if the degree of uncertainty in binaural cues was reduced, thresholds decreased towards thresholds in the conditions without any stimulus uncertainty. In the analysis of the data, stimulus uncertainty was expressed in terms of three theories of binaural processing: the interaural correlation, the EC theory, and a model based on the processing of interaural intensity differences (IIDs) and interaural time differences (ITDs). This analysis revealed that none of the theories tested could quantitatively account for the observed thresholds. In addition, it was found that, in conditions with stimulus uncertainty, predictions based on correlation differ from those based on the EC theory.

Attention↗

PubMed1998

The relationships among uncertainty, social support, and psychological distress in adolescents recently diagnosed with cancer.

Uncertainty in illness about diagnosis, symptoms, prognosis, treatments, and relationships with health professionals is a major psychosocial stressor for adolescents recently diagnosed with cancer. In this study, the theoretical linkages of the uncertainty in illness theory of perceived social support, uncertainty, and psychological distress were tested. Respondents consisted of 60 adolescents between the ages of 14 and 22 years who were recently diagnosed with cancer. Data were generated by three questionnaires and analyzed using Pearson product moment coefficients and multiple regressional analyses. Hypotheses tested were that among adolescents with cancer (1) there will be an inverse relationship between perceived social support and uncertainty; (2) there will be a positive relationship between uncertainty and psychological distress; (3) there will be an inverse relationship between perceived social support and psychological distress; and (4) there will be an inverse relationship between perceived social support and psychological distress when controlling for uncertainty. Findings were as follows: the first three hypotheses were supported; there was no relationship between perceived social support and psychological distress when controlling for uncertainty. An interaction effect of perceived social support and uncertainty explained 39% of the variance in psychological distress.

Adolescent↗

PubMed1991

Saccadic suppression and stimulus uncertainty.

Saccadic suppression is a decline in detectability of a weak flash presented during a saccadic eye movement. We examined the hypothesis of Matin [Psychol. Bull. 81, 899 (1974)] that saccadic suppression may be due to increased stimulus uncertainty during the saccade. Uncertainty could arise from variability and inhomogeneities in the visual frame of reference translation that must accompany a saccade. We measured an average 0.6-log-unit suppression for a brief foveal 1 degree flash in a light-adapted detection task. Receiver-operating-characteristic (ROC) slopes for flash detection during saccades, compared with those when fixating, were reduced, indicating the presence of increased uncertainty. The magnitude of this uncertainty change was estimated and found to be consistent with that required to account for the measured detectability decline. When a flashed pedestal was employed to reduce the effect of uncertainty, there was no saccadic suppression and no ROC slope change. Also, spatially separate flashed markers, intended to reduce uncertainty, led to a significant reduction in saccadic suppression for one of two subjects. Our results are consistent with the hypothesis that a saccade leaves the observer with increased uncertainty as to which subjective visual direction to attend for a stimulus of fixed retinal locus. The magnitude of this uncertainty change can account fully for the saccadic suppression measured.

Eye Movements↗

PubMedDate not supplied

Uncertainty assessment of the model RICEWQ in northern Italy.

Model predictions are often seriously affected by uncertainties arising from many sources. Ignoring the uncertainty associated with model predictions may result in misleading interpretations when the model is used by a decision-maker for risk assessment. In this paper, an analysis of uncertainty was performed to estimate the uncertainty of model predictions and to screen out crucial variables using a Monte Carlo stochastic approach and a number of statistical methods, including ANOVA and stepwise multiple regression. The model studied was RICEWQ (Version 1.6.1), which was used to forecast pesticide fate in paddy fields. The results demonstrated that the paddy runoff concentration predicted by RICEWQ was in agreement with field measurements and the model can be applied to simulate pesticide fate at field scale. Model uncertainty was acceptable, runoff predictions conformed to a log-normal distribution with a short right tail, and predictions were reliable at field scale due to the narrow spread of uncertainty distribution. The main contribution of input variables to model uncertainty resulted from spatial (sediment-water partition coefficient and mixing depth to allow direct partitioning to bed) and management (time and rate of application) parameters, and weather conditions. Therefore, these crucial parameters should be carefully parameterized or precisely determined in each site-specific paddy field before the application of the model, since small errors of these parameters may induce large uncertainty of model outputs.

Forecasting↗

PubMedDate not supplied

Simulating solute transport in a structured field soil: uncertainty in parameter identification and predictions.

Dual-permeability models have been developed to account for the significant effects of macropore flow on contaminant transport, but their use is hampered by difficulties in estimating the additional parameters required. Therefore, our objective was to evaluate data requirements for parameter identification for predictive modeling with the dual-permeability model MACRO. Two different approaches were compared: sequential uncertainty fitting (SUFI) and generalized likelihood uncertainty estimation (GLUE). We investigated six parameters controlling macropore flow and pesticide sorption and degradation, applying MACRO to a comprehensive field data set of bromide andbentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one-2,2dioxide] transport in a structured soil. The GLUE analyses of parameter conditioning for different combinations of observations showed that both resident and flux concentrations were needed to obtain highly conditioned and unbiased parameters and that observations of tracer transport generally improved the conditioning of macropore flow parameters. The GLUE "behavioral" parameter sets covered wider parameter ranges than the SUFI posterior uncertainty domains. Nevertheless, estimation uncertainty ranges defined by the 5th and 95th percentiles were similar and many simulations randomly sampled from the SUFI posterior uncertainty domains had negative model efficiencies (minimum of -3.2). This is because parameter correlations are neglected in SUFI and the posterior uncertainty domains were not always determined correctly. For the same reasons, uncertainty ranges for predictions of bentazone losses through drainflow for good agricultural practice in southern Sweden were 27% larger for SUFI compared with GLUE. Although SUFI proved to be an efficient parameter estimation tool, GLUE seems better suited as a method of uncertainty estimation for predictions.

Benzothiadiazines↗

PubMed2002

Evaluating and expressing the propagation of uncertainty in chemical fate and bioaccumulation models.

First-order analytical sensitivity and uncertainty analysis for environmental chemical fate models is described and applied to a regional contaminant fate model and a food web bioaccumulation model. By assuming linear relationships between inputs and outputs, independence, and log-normal distributions of input variables, a relationship between uncertainty in input parameters and uncertainty in output parameters can be derived, yielding results that are consistent with a Monte Carlo analysis with similar input assumptions. A graphical technique is devised for interpreting and communicating uncertainty propagation as a function of variance in input parameters and model sensitivity. The suggested approach is less calculationally intensive than Monte Carlo analysis and is appropriate for preliminary assessment of uncertainty when models are applied to generic environments or to large geographic areas or when detailed parameterization of input uncertainties is unwarranted or impossible. This approach is particularly useful as a starting point for identification of sensitive model inputs at the early stages of applying a generic contaminant fate model to a specific environmental scenario, as a tool to support refinements of the model and the uncertainty analysis for site-specific scenarios, or for examining defined end points. The analysis identifies those input parameters that contribute significantly to uncertainty in outputs, enabling attention to be focused on defining median values and more appropriate distributions to describe these variables.

Environmental Pollutants↗

PubMed1990

Parental uncertainty in critical care hospitalization of children.

The purpose of this qualitative study was to explore the dimensions of uncertainty, including the source, family effect, and parental response, of parents whose child was hospitalized in a pediatric intensive care unit (PICU). A convenience sample of 13 parents of 8 critically ill children served as subjects for this study. Data were collected using a modified grounded theory method with 1 to 1-1/2 hour interviews of parents within 2-4 days after admission of their child to the PICU. A model of PICU uncertainty was derived which identified four areas in which ambiguity, conflicting information, or perceived inefficiency gave rise to uncertainty. These areas included: environmental uncertainty, illness uncertainty, caregiver uncertainty, and family systems uncertainty. Findings are related to Mishel's Theory of Uncertainty (1987) and implications for pediatric nursing research are discussed.

Adult↗

PubMed1996

The influence of illness severity and family resources on maternal uncertainty during critical pediatric hospitalization.

BACKGROUND: Psychological management of parents during a child's critical illness is a challenge to intensive care nurses because of the uncertainty that accompanies hospitalization. OBJECTIVE: To explore the relationship among illness severity, family resources, and maternal uncertainty during the initial stage of a child's hospitalization in a pediatric intensive care unit for a life-threatening illness. METHODS: A convenience sample of 40 mothers rated perceptions of uncertainty (using Mishel's Uncertainty of Illness Scale: Parent Child Form), family cohesion (using Olson's Family Adaptability and Cohesion Evaluation Scale), and social support (using Norbeck's Social Support Questionnaire). Illness severity was estimated with the Pediatric Risk of Mortality Scale. RESULTS: ¿ Results showed a positive association between illness severity and maternal uncertainty and a negative association between family cohesion and maternal uncertainty. Severity of illness contributed less to maternal uncertainty than did family cohesion. CONCLUSIONS: Family relationship are important factors to consider when clinicians estimated the effect on parents of their child's critical illness, particularly when uncertainty over their child's outcome may lead to parental stress that can interfere with coping and child management. (American Journal of Critical Care.)

Adolescent↗

PubMed1998

Survivors of breast cancer: illness uncertainty, positive reappraisal, and emotional distress.

PURPOSE/OBJECTIVES: To explore variables associated with illness uncertainty and emotional distress for disease-free survivors of breast cancer. DESIGN: Cross-sectional, descriptive, and correlational. SETTING: Regional cancer center in the southeastern United States. SAMPLE: 109 women one to six years post-treatment for stage I-III nonmetastatic breast cancer. METHODS: Face-to-face data gathering using five questionnaires with established reliability. MAIN RESEARCH VARIABLES: Symptom distress, concurrent illness, fear of recurrence, illness uncertainty, positive reappraisal, and emotional distress. FINDINGS: The antecedent variables symptom distress, fear of recurrence, and concurrent illness problems were positively related to illness uncertainty. Illness uncertainty and the antecedent variables were positively related to emotional distress. The antecedent variables explained 40% of the variance in uncertainty. Uncertainty, its antecedents, and positive reappraisal collectively explained 51% of the variance in emotional distress. CONCLUSIONS: Illness uncertainty related to symptoms and fear of recurrence was linked with emotional distress for some women, even years after treatment. Positive reappraisal may help to reduce this distress. IMPLICATIONS FOR NURSING PRACTICE: Nurses need to identify, monitor, and assist women who are at risk for illness uncertainty and emotional distress after breast cancer treatment. They also should explore with women positive, growth-promoting aspects of breast cancer, as well as aspects of the disease that are threatening.

Adult↗

PubMed2006

Uncertainty and perceived personal control among parents of children with rare chromosome conditions: the role of genetic counseling.

Little is known about the impact of genetic counseling on parental uncertainty or perceived control regarding the prognosis of a child with a chromosomal disorder. By exploring the parents' concerns and needs surrounding the child's diagnosis, a genetic provider can help to facilitate effective coping. This study tested the association of measures of parental uncertainty and perceived control with the perceived helpfulness of the genetic counselor. A survey was distributed to 875 members of the Chromosome Deletion Outreach (CDO) support group. We hypothesized that parents' perceptions about the helpfulness of the genetic counselor would modify the relationship between perceived uncertainty, perceived control, and coping. Among the 363 respondents, there was a significant negative correlation of the perceived helpfulness of seeing a genetic counselor with the levels of uncertainty (rs = -0.20, P-value < 0.001). Lower perceived helpfulness of the genetic counselor, along with less perceived personal control, less benefit of a diagnosis, and lower parental age were significant predictors of the highest perceptions of uncertainty. The Transactional Model of Stress and Coping was used as a framework for interpreting the relationships between parental uncertainty, perceived control, and outcome variables. There was a significant positive correlation between parents' perceived personal control and their reports of helpfulness of the genetic counselor (rs = 0.20, P-value <0.0006). Genetic counseling can be enhanced for parents faced with rare disorders by using interventions focused on reducing feelings of uncertainty and enhancing feelings of control.

Adaptation, Psychological↗

PubMed2005

Uncertainty assessment of spatial patterns of soil organic carbon density using sequential indicator simulation, a case study of Hebei province, China.

The spatial patterns of soil organic carbon (SOC) are closely related to the global climate change. In quantifying the spatial patterns of SOC density, the concept of uncertainty of the SOC density values at unsampled locations is particularly important because such uncertainty can be propagated into the subsequent global climate change modelling and has fundamental impacts on the ultimate results of the model. A total of 361 SOC density data of topsoil (0-20 cm) in Hebei province and sequential indicator simulation (SIS) were applied to perform a conditional stochastic simulation in this study to quantitatively assess the uncertainty of mapping SOC density. The results showed that a great variation exists in the SOC density data. The conditional variance of 500 realizations generated by SIS was larger in mountainous areas of the study area where the SOC density fluctuated the most, and the uncertainty was smaller on the plain area where SOC density was consistently small. Realizations generated by SIS can represent the possible spatial patterns of SOC density without smoothing effect. A set of realizations can be used to explore all possible spatial patterns of SOC density and provide a visual and quantitative measure of the spatial uncertainty of mapping SOC density. With a given threshold of SOC density, SIS can quantitatively assess both local uncertainty and spatial uncertainty of SOC density that is greater the threshold.

Carbon↗

PubMed2025

Modeling unknowns: A vision for uncertainty-aware machine learning in healthcare.

The integration of machine learning (ML) into healthcare is accelerating, driven by the proliferation of biomedical data and the promise of data-driven clinical support. A key challenge in this context is managing the pervasive uncertainty inherent in medical reasoning and decision-making. Despite its recognized importance, uncertainty is often underrepresented in the design and evaluation of clinical AI systems. Here we report an editorial overview of a special issue dedicated to uncertainty modeling in medical AI, which gathers theoretical, methodological, and practical contributions addressing this critical gap. Across these works, authors reveal that fewer than 4% of studies address uncertainty explicitly, and propose alternative design principles-such as optimizing for clinical net benefit or embedding explainability with confidence estimates. Notable contributions include the RelAI system for real-time prediction reliability, empirical findings on how uncertainty communication shapes clinical interpretation, and benchmarks for out-of-distribution detection in tabular data. Furthermore, this issue highlights the use of causal reasoning and anomaly detection to enhance system robustness and accountability. Together, these studies argue that representing, communicating, and operationalizing uncertainty are essential not only for clinical safety but also for building trust in AI-driven care. This special issue thus repositions uncertainty from a limitation to a foundational asset in the responsible deployment of ML in healthcare.

Machine Learning↗

PubMed2005

Uncertainty method improved on best-worst case analysis in a binary meta-analysis.

BACKGROUND: Most systematic reviewers aim to perform an intention-to-treat meta-analysis, including all randomized participants from each trial. This is not straightforward in practice: reviewers must decide how to handle missing outcome data in the contributing trials. OBJECTIVE: To investigate methods of allowing for uncertainty due to missing data in a meta-analysis. STUDY DESIGN AND SETTING: The Cochrane Library was surveyed to assess current use of imputation methods. We developed a methodology for incorporating uncertainty, with weights assigned to trials based on uncertainty interval widths. The uncertainty interval for a trial incorporates both sampling error and the potential impact of missing data. We evaluated the performance of this method using simulated data. RESULTS: The survey showed that complete-case analysis is commonly considered alongside best-worst case analysis. Best-worst case analysis gives an interval for the treatment effect that includes all of the uncertainty due to missing data. Unless there are few missing data, this interval is very wide. Simulations show that the uncertainty method consistently has better power and narrower interval widths than best-worst case analysis. CONCLUSION: The uncertainty method performs consistently better than best-worst case imputation and should be considered along with complete-case analysis whenever missing data are a concern.

Antimalarials↗