1,551 research outputs found
Validity and reliability of the DMSES UK : a measure of self-efficacy for type 2 diabetes self-management
Objectives Self-efficacy is an important outcome measure of self-management interventions. We aimed to establish UK validity and reliability of the diabetes management self-efficacy scale (DMSES).
Methods The 20 item DMSES was available for Dutch and US populations. Consultation with people with type 2 diabetes and health professionals established UK content and face validity resulting in item reduction to 15. Participants were adults with type 2 diabetes enrolled in a randomised controlled trial (RCT) of the diabetes manual, a self-management education intervention, with an HbA1c over 7% and who understood English. Baseline trial data and follow-up control group data were used.
Results A total of 175 participants completed all 15 items. Pearson’s correlation coefficient of −0.46 (P 0.30. Cronbach’s alpha was 0.89 over all items.
Conclusion This evaluation demonstrates that the scale has good internal reliability, internal consistency, construct validity, criterion validity, and test-retest reliability.
Practice Implications The 15 item DMSES UK is suitable for use in research and clinical settings to measure the self-efficacy of people living with type 2 diabetes in managing their diabetes
Effects of the diabetes manual 1:1 structured education in primary care
Aims
To determine the effects of the Diabetes Manual on glycaemic control, diabetes-related distress and confidence to self-care of patients with Type 2 diabetes. Methods
A cluster randomized, controlled trial of an intervention group vs. a 6-month delayed-intervention control group with a nested qualitative study. Participants were 48 urban general practices in the West Midlands, UK, with high population deprivation levels and 245 adults with Type 2 diabetes with a mean age of 62 years recruited pre-randomization. The Diabetes Manual is 1:1 structured education designed for delivery by practice nurses. Measured outcomes were HbA1c, cardiovascular risk factors, diabetes-related distress measured by the Problem Areas in Diabetes Scale and confidence to self-care measured by the Diabetes Management Self-Efficacy Scale. Outcomes were assessed at baseline and 26 weeks. Results
There was no significant difference in HbA1c between the intervention group and the control group [difference −0.08%, 95% confidence interval (CI) −0.28, 0.11]. Diabetes-related distress scores were lower in the intervention group compared with the control group (difference −4.5, 95% CI −8.1, −1.0). Confidence to self-care Scores were 11.2 points higher (95% CI 4.4, 18.0) in the intervention group compared with the control group. The patient response rate was 18.5%. Conclusions
In this population, the Diabetes Manual achieved a small improvement in patient diabetes-related distress and confidence to self-care over 26 weeks, without a change in glycaemic control. Further study is needed to optimize the intervention and characterize those for whom it is more clinically and psychologically effective to support its use in primary care
Stochastic Scheduling of Wind-Integrated Power Systems
The cost of balancing supply and demand will increase as power systems are decarbonised,
because the requirement for operating reserve will increase with the wind
penetration, while the flexible fossil-fuel generators, which have been the traditional
providers of reserve, will be displaced. While these costs can be mitigated through increased
interconnection, energy storage, and demand-side market participation, a fundamental
review of system operational policy is also needed to ensure that the available
reserves are scheduled optimally. Stochastic Unit Commitment can find the commitment
and dispatch decisions that minimise the expected system costs, including the potential
costs of unserved energy, given the short-term uncertainties of wind and other variables.
It therefore has the potential to provide the most efficient possible paradigm for the operation
of wind-integrated systems. Because the system’s ability to respond to wind fluctuations
is constrained by intertemporal limitations of the other components, time domain
simulations are needed to assess the performance of different operational strategies or
generator fleet characteristics. However, Stochastic Unit Commitment has demanding
computational requirements that can render it impractical for long-term simulations of a
large power system.
This thesis develops a new tool for simulating the operation of large, wind-integrated
power systems using stochastic scheduling, with the emphasis on computational efficiency.
Embedded within it are new models for characterising time series of aggregated
wind output and wind forecast errors; these models are integrated with a Stochastic Unit
Commitment algorithm within a Monte Carlo framework. We explore simplifications
that can mitigate the computational burden without unduly compromising the quality
of the analysis. Simulations with the tool show that fully stochastic scheduling can reduce
operating costs by around 4% relative to traditional deterministic approaches, in a
system with a 50% wind penetration
A Labelled Analytic Theorem Proving Environment for Categorial Grammar
We present a system for the investigation of computational properties of
categorial grammar parsing based on a labelled analytic tableaux theorem
prover. This proof method allows us to take a modular approach, in which the
basic grammar can be kept constant, while a range of categorial calculi can be
captured by assigning different properties to the labelling algebra. The
theorem proving strategy is particularly well suited to the treatment of
categorial grammar, because it allows us to distribute the computational cost
between the algorithm which deals with the grammatical types and the algebraic
checker which constrains the derivation.Comment: 11 pages, LaTeX2e, uses examples.sty and a4wide.st
A nonparametric algorithm for optimal stopping based on robust optimization
Optimal stopping is a fundamental class of stochastic dynamic optimization
problems with numerous applications in finance and operations management. We
introduce a new approach for solving computationally-demanding stochastic
optimal stopping problems with known probability distributions. The approach
uses simulation to construct a robust optimization problem that approximates
the stochastic optimal stopping problem to any arbitrary accuracy; we then
solve the robust optimization problem to obtain near-optimal Markovian stopping
rules for the stochastic optimal stopping problem. In this paper, we focus on
designing algorithms for solving the robust optimization problems that
approximate the stochastic optimal stopping problems. These robust optimization
problems are challenging to solve because they require optimizing over the
infinite-dimensional space of all Markovian stopping rules. We overcome this
challenge by characterizing the structure of optimal Markovian stopping rules
for the robust optimization problems. In particular, we show that optimal
Markovian stopping rules for the robust optimization problems have a structure
that is surprisingly simple and finite-dimensional. We leverage this structure
to develop an exact reformulation of the robust optimization problem as a
zero-one bilinear program over totally unimodular constraints. We show that the
bilinear program can be solved in polynomial time in special cases, establish
computational complexity results for general cases, and develop polynomial-time
heuristics by relating the bilinear program to the maximal closure problem from
graph theory. Numerical experiments demonstrate that our algorithms for solving
the robust optimization problems are practical and can outperform
state-of-the-art simulation-based algorithms in the context of widely-studied
stochastic optimal stopping problems from high-dimensional option pricing
- …