Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Problem Formulation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

[Formulating problems of ecological diseases. Approaches to etiopathogenesis, classification and diagnosis of ecological diseases due to chemicals].

Our long-standing clinical trials proved nonspecific and stress factors contributing into environmental diseases. The studies helped to define traumatic variant of biologic stress, to describe its trigger mechanisms. The authors analyzed physiologic mechanisms of stress-related diseases, role of autonomous nervous system in formation of environmental diseases. Clinical classification of acute and chronic environmental diseases is given, with consideration of their diagnosis.

Adaptation, Physiological↗

Hazard identification for contaminants.

In recent years, the recognition of generation of large quantities of toxicants and their by-products due to the industrial and/or cultural activities and transport and their persistence in the environment and biological activities brings out the necessity and importance of their assessment of risk they pose to the ecosystems (e.g. aquatic environment-coastal waters, rivers, lakes and ground water). Indeed, understanding the impacts of contaminants on the environment, including the organisms which live in it, is rather complicated. Nevertheless, the need for protection of the scarce natural resources in the environment and wiser use of them brings the necessity and importance of focusing more attention to the issue. Accordingly the process of ecological risk assessment (ERA) has evolved rapidly since the Environmental Protection Agency (EPA) issued a framework for ecological risk assessment in 1992. The ecological risk assessment involves three stages in a continuous process: (1) problem formulation (problem identification-hazard identification), (2) the analysis of exposure and effects and (3) risk characterisation. Risk management follows the risk characterisation. Of these stages, problem identification is the most critical one which establishes the direction and scope of the ecological risk assessment. The stage involves identifying the actual environmental value(s) to be protected (assessment endpoints) and selecting ways in which these can be measured and evaluated (measurement endpoints). The accuracy of the risk estimation is largely based on the availability of the key information about the contaminant characteristics, ecosystem at risk and ecological effects and the less uncertainty associated with them. The key information required during this phase of the risk assessment process are as follows: (a) potential/actual contaminant of concern, (b) source of contaminant; current and historic use, (c) mode of action of the contaminant, (d) contaminant characteristics (e.g. physical/chemical properties and environmental behaviour, persistence in the ecosystem, transformation products and bioaccumulation), (e) ecosystem potentially at risk and (f) areas of uncertainty. Finally based on these information a conceptual model has to be developed to define the possible exposure and assessment scenarios. Herein, the aforementioned key issues concerning the problem-hazard identification stage of ecological risk assessment for contaminants have been briefly reviewed.

Chemical Phenomena↗

Formulation and (bio)availability problems of drug formulations in birds.

Most drugs used for the treatment of birds are not formulated for birds. Therefore the availability of drugs for birds and their administration routes largely depend on formulations available for man, mammals and to some extent poultry. The problems with the application of existing formulations, the drug concentrations and the many different avian species are discussed. The desire of the avian veterinarian for the combination of several active compounds presents special problems. This again requires extra data on the interactions in galenic, pharmaceutic, pharmacokinetic and dynamic phases, which are generally not readily available.

Animal Feed↗

Problems in formulating method-insensitive proficiency testing materials.

Significant problems exist in formulating method-insensitive proficiency materials. Many steps are required in processing human plasma, and difficult choices are involved in the selection of appropriate materials to be added to the processed plasma. Additionally, analytes may vary widely in their recovery from method to method. To enhance understanding of the procedures and problems involved in the development and manufacture of proficiency materials, a number of constituents and their method-specific recoveries are reviewed.

Bias↗

Interpersonal psychotherapy of depressed HIV-positive outpatients.

In an open pilot study, 23 depressed adults infected with human immunodeficiency virus were treated using interpersonal therapy. Twenty subjects recovered from depression after a mean of 16 sessions. The authors discuss six aspects of interpersonal therapy that make it useful with depressed HIV-infected persons: psychoeducation about the sick role; a here-and-now framework; formulation of problems from an interpersonal perspective; exploration of options for changing dysfunctional behavior patterns; identification of focused interpersonal problem areas (grief, role transition, interpersonal disputes, and interpersonal deficits); and the confidence therapists gain from a systematic approach to problem formulation and treatment. Results suggest that mental health professionals should consider interpersonal therapy as a treatment for depressed HIV-positive patients.

AIDS-Related Opportunistic Infections↗

Obstacle avoidance for kinematically redundant manipulators using a dual neural network.

One important issue in the motion planning and control of kinematically redundant manipulators is the obstacle avoidance. In this paper, a recurrent neural network is developed and applied for kinematic control of redundant manipulators with obstacle avoidance capability. An improved problem formulation is proposed in the sense that the collision-avoidance requirement is represented by dynamically-updated inequality constraints. In addition, physical constraints such as joint physical limits are also incorporated directly into the formulation. Based on the improved problem formulation, a dual neural network is developed for the online solution to collision-free inverse kinematics problem. The neural network is simulated for motion control of the PA10 robot arm in the presence of point and window-shaped obstacle.

Journal Article↗

Defining populations: a key step in identifying spatial and temporal scales.

The scale at which ecological risk assessors frame their analyses can be driven by a number of considerations. In many cases, the selection of the scale is among the most important decisions within the 'problem-formulation' phase of the ecological risk characterization. The scale of a risk characterization is often defined based on ownership boundaries, ecological, or habitat boundaries and/or physical and hydrogeological boundaries (e.g., watersheds). With increasing value being placed on consideration of spatial scales in risk characterization, the need to define a scale that balances analytical and ecological realities is imperative. Defining the spatial scale based on the scale of a population offers the risk assessor the opportunity to improve the ecological relevance of the risk characterization. Arriving at a single operational definition of a population would be difficult and not appropriate because of the variability in sites, issues, and management goals; however, we can begin to review operational definitions and establish analytical frameworks by which to select the appropriate, site-specific scale within the problem-formulation phase. Defining a scale based on a combination of ecological and site ownership considerations and the inclusion of habitat quality in the assessment of scale can improve the power and relevance of the problem formulation and risk characterization. In this analysis, we assess methods for incorporating spatial considerations into risk analyses, beginning with developing an understanding of the context of a site within the larger landscape. Clearly defining the scale of an assessment including the operational definition of populations is an important step in the problem formulation. Within a site or landscape, the scale may be refined further based on the percentage of the land within the scale of the analysis that provides habitat for a given species.

Animals↗

Patient-practitioner agreement: does it matter?

BACKGROUND: Good communication is a crucial clinical skill. Previous research demonstrated better clinical outcomes when practitioners and patients agree about the nature of patients' core presenting complaints. We investigated the nature of this agreement and its impact on outcome among depressed primary care patients. METHOD: We compared presenting problem formulations completed by patients, GPs and therapists in a primary care randomized controlled trial of cognitive-behavioural therapy and non-directive counselling for depression. Participants compiled formulations from a list of 13 potential problems of self-completed questionnaires. Subjects scored at least 14 on the Beck Depression Inventory (BDI) at baseline. Outcome measure for this study included BDI at 4 and 12 months, failure to attend for therapy when referred, dropout from therapy and patient satisfaction. RESULTS: Among 464 trial patients, 395 received therapy. Patient baseline problem formulations included significantly more items than GPs, who identified significantly more items than therapists. Agreement levels varied according to a range of patient and professional variables. While patients in complete agreement with their therapists about their main problem after assessment had lower average BDI scores at 12 months (9.7 v. 12.8, P=0.03); we found no other significant associations between the extent of agreement and clinical outcome. There were significant (but relatively weak) associations between agreement and aspects of patient satisfaction. CONCLUSION: Our results suggest that detailed mutual understanding of the presenting complaints may be less important than agreement that the core problem is psychological, and that referral for psychological therapy is appropriate.

Adolescent↗

Between universalism and relativism: a conceptual exploration of problems in formulating and applying international biomedical ethical guidelines.

In this paper, the author attempts to explore some of the problems connected with the formulation and application of international biomedical ethical guidelines, with particular reference to Africa. Recent attempts at revising and updating some international medical ethical guidelines have been bedevilled by intractable controversies and wrangling regarding both the content and formulation. From the vantage position of relative familiarity with both African and Western contexts, and the privilege of having been involved in the revision and updating of one of the international ethical guidelines, the author reflects broadly on these issues and attempts prescribing an approach from both the theoretical and practical angles liable to mitigate, if not completely eliminate, some of the problems and difficulties.

Developing Countries↗

The study of direct-to-consumer advertising for prescription drugs.

OBJECTIVES: The objectives of this article are to (1) identify key methodological issues related to investigating the effects of direct-to-consumer advertising (DTCA) for prescription drugs, (2) highlight opportunities and challenges that these issues pose, and (3) provide suggestions to address these challenges and opportunities from a social and administrative pharmacy perspective. METHODS: Through a review of existing literature and consultation with research colleagues, we identified 3 broad issues regarding the study of DTCA for prescription drugs: (1) the importance of problem formulation, (2) the role of health behavior and decision-making perspectives, and (3) data collection and data analysis challenges and opportunities. Based upon our findings, we developed recommendations for future research in this area. RESULTS: Clear problem formulation will be instructive for prioritizing research needs and for determining the role that health behavior and decision-making perspectives can serve in DTCA research. In addition, it appears that cluster bias, nonlinear relationships, mediating/moderating effects, time effects, acquiescent response, and case mix are particularly salient challenges for the DTCA research domain. CONCLUSIONS: We suggest that problem formulation, selection of sound theories upon which to base research, and data collection and data analysis challenges are key methodological issues related to investigating the effects of DTCA for prescription drugs.

Advertising↗

Scientific research, stakeholders, and policy: continuing dialogue during research on radionuclides on Amchitka Island, Alaska.

It is increasingly clear that a wide range of stakeholders should be included in the problem formulation phase of research aimed at solving environmental problems; indeed the inclusion of stakeholders at this stage has been formalized as an integral part of ecological risk assessment. In this paper, we advocate the additional inclusion of stakeholders in the refinement of research methods and protocols and in the execution of the research, rather than just at the final communication and reporting phase. We use a large study of potential radionuclide levels in marine biota around Amchitka Island as a case study. Amchitka Island, in the Aleutian Island Chain of Alaska, was the site of three underground nuclear tests (1965-1971). The overall objective of the biological component of the study was to collect a range of marine biota for radionuclide analysis that could provide data for assessing current food safety and provide a baseline for developing a plan to monitor human and ecosystem health in perpetuity. Stakeholders, including regulators (State of Alaska), resource trustees (US Fish and Wildlife Service, State of Alaska), representatives of the Aleut and Pribilof Island communities, the Department of Energy (DOE), and others, were essential for plan development. While these stakeholders were included in the initial problem formulation and approved science plan, we also included them in the refinement of protocols, selection of bioindicators, selection of a reference site, choice of methods of collection, and in the execution of the study itself. Meetings with stakeholders resulted in adding (or deleting) bioindicator species and tissues, prioritizing target species, refining sampling methods, and recruiting collection personnel. Some species were added because they were important subsistence foods for the Aleuts, and others were added because they were ecological equivalents to replace species deleted because of low population numbers. Two major refinements that changed the research thrust were (1) the inclusion of Aleut hunters and fishers on the biological expedition itself to ensure that subsistence foods and methods were represented, and (2) the addition of a fisheries biologist on a NOAA research trawler to allow sampling of commercial fishes. Although the original research design called for the collection of biota by Aleut subsistence fishermen, and by a commercial fishing boat, the research was modified with continued stakeholder input to actually include Aleuts and a fisheries biologist on the expeditions to ensure their representation. The inclusion of stakeholders during the development of protocols and the research itself improved the overall quality of the investigation, while making it more relevant to the interested and affected parties. Final responsibility for the design and execution of the research and radionuclide analysis rested with the researchers, but the process of stakeholder inclusion made the research more valuable as a source of credible information and for public policy decisions.

Alaska↗

Primary care multidimensional model: a framework for formulating health problems in a primary care setting.

There is a need to develop a systematic method for integrating organic, emotional, personal, and environmental data of a patient's lifestyle into the management of health problems. The Primary Care Multidimensional Model (PCMM) was developed to assist in the formulation of an individual's health problem, whether categorized as biological, psychological or social. The PCMM was applied to 276 health problems attended in a consecutive sample of 84 adult patients cared for in an inner city primary care setting. Seventy-five percent of the problems were categorized as primarily biological, 14% as psychological, and 9% as social. Sixty-seven percent of the "biological" problems were found to have emotional, personal, or environmental variables from the patient's lifestyle considered relevant at the time of the study visit. All psychological and social problems were likewise multidimensional. In the population studied, over 75% of the health problems attended in a primary care practice fulfilled the biopsychosocial model of illness as defined by the PCMM. The heuristic value of this study is discussed.

Adaptation, Psychological↗