Remote Sensing Methods and Applications for Detecting Change in Forest Ecosystems

Forest ecosystems are being altered by climate change, invasive species, and additional stressors. Our ability to detect these changes and quantify their impacts relies on detailed data across spatial and temporal scales. This dissertation expands the ecological utility of long-term satellite imagery by developing high quality forest mapping products and examining spatiotemporal changes in tree species abundance and phenology across the northeastern United States (US; the ‘Northeast’). Species/genus-level forest composition maps were developed by integrating field data and Landsat images to model abundance at a sub-pixel scale. These abundance maps were then used to 1) produce a more detailed, accurate forest classification compared to similar products and 2) construct a 30-year time-series of abundance for eight common species/genera. Analyzing the time-series data revealed significant abundance trends in notable species, including increases in American beech (Fagus grandifolia) at the expense of sugar maple (Acer saccharum). Climate was the dominant predictor of abundance trends, indicating climate change may be altering competitive relationships. Spatiotemporal trends in deciduous forest phenology – start and end of the growing season (SOS/EOS) – were examined based on MODIS imagery from 2001-2015. SOS exhibited a slight advancing trend across the Northeast, but with a distinct spatial pattern: eastern ecoregions showed advance and western ecoregions delay. EOS trended substantially later almost everywhere. SOS trends were linked to winter-spring temperature and precipitation trends; areas with higher elevation and fall precipitation anomalies had negative associations with EOS trends. Together, this work demonstrates the value of remote sensing in furthering our understanding of long-term forest responses to changing environmental conditions. By highlighting potential changes in forest composition and function, the research presented here can be used to develop forest conservation and management strategies in the Northeast

Academic English course for the health sciences: evolution towards a flipped classroom

The transition from university face-to-face teaching to blended learning can be challenging. This educational design research study investigated the optimal design for a blended and flipped learning approach to a scientific English course and the impact on student motivation and learning of incorporating pedagogical principles from adult and work-based learning. Using student feedback and teacher reflections, we evaluated three iterative cycles of development from trialling of e-modules in a face-to-face course, to a fully online course, to a blended learning approach with a flipped classroom. We found that student participants were increasingly satisfied over time and conclude that the final course design is the optimal approach for our context. Integrating principles of direct interest from adult learning and involvement of current work supported participant motivation, while self-paced e-modules allowed direct application of new knowledge. Coherence between pre-class, in-class, and post-class activities in the flipped classroom helped ensure relevant learning activities

Adverse effects of benzodiazepines

The growing realisation that the benzodiazepines have potential for causing serious harm has caused concern due to their wide and common use. This has stimulated interest in the costs and benefits of their use. This paper is a review of the adverse effects of benzodiazepines, and concentrates on four areas of particular concern: drug dependence which the consequent withdrawal symptoms; psychological effects while on the drugs; use by the elderly’ and tolerance to the drug effects. Although the phenomenon of a benzodiazepine withdrawal syndrome is generally accepted, there is still controversy over the frequency amongst users. A number of major studies are reviewed here, and the main methodological issues are discussed. These include definition of the withdrawal symptoms, selection of subjects, and use of double-blind, placebo-controlled conditions. The studies investigating impairment with benzodiazepine use deal mainly with motor performance and coordination, although there is a large group of studies looking at the effect of the drugs on memory. Although the studies reviewed make a considerable contribution to the understanding of the effects of benzodiazepines, they focus on physiological and specific psychological variables, rather than more global measures of functioning and behaviour. It is suggested here that this emphasis needs to change in order to obtain a clearer picture of how benzodiazepines affect quality of life. Future studies should also be prospective in design, and include clear criteria for the selection of subjects and for the definition of withdrawal symptoms.benzodiazepine, adverse effects, drug, withdrawl

QALYs and their use by the health service

Despite considerable progress and achievements in health care over the last century, we still cannot give every ill person as full a treatment as possible. With limited resources, decisions have to be made to determine priorities in the health care system. These decisions should be based on both costs of resource inputs and on the health outcome for the patients involved. However, there is little emphasis on outcome data in present decisions and its importance and usefulness needs to be highlighted. In a joint project between the University of York and the North Western Regional Health Authority (NWRHA), one measure of health outcome, the quality-adjusted-life-year (QALY) was combined with cost data to provide a new criterion for use in determining resource allocation. The NWRHA found this cost/QALY data to be a useful adjunct to their decision-making and they will require details of both resource inputs and of health outcome to be given in subsequent bids. It is hoped that with the further development of the QALY-type measurement, it will be easier to include such information in the decision-making process and those concerned will be reminded that the quality of life is a factor that should not be ignored. In this paper the background to the project and the methods used are described. This is followed by a discussion of the QALY results in terms of their usefulness to a health authority, and in the context of some shortcomings that have yet to be resolved.QALY

Standard Gamble user manual: props and self-completion methods

In 1992, the Measurement and Valuation of Health (MVH) Group at the Centre for Health Economics conducted a study with Social and Community Planning Research (SCPR) comparing different methods of valuing health states (Dolan et al, 1993). A random sample of 335 members of the general population were interviewed in their own homes by specially trained interviewers. Each respondent was asked to value a series of health states using two different valuation methods – Standard Gamble (SG) and Time Trade-Off (TTO). Considerable time and energy went into the production of the protocols for the interviews. Standard methodology (derived primarily from research in Canada and the USA) for both the SG and TTO methods involves the use of specially designed boards and cards. He SG procedure typically uses a ‘probability wheel’ which allows different probabilities of health outcomes to be presented to the respondent, while the TTO typically uses a horizontal sliding scale which allows the length of time spent in a health state to be varied. SG and TTO boards based on the standard methodology were piloted as part of the MVH study and it was found that substantial modifications were required to simplify the material for both the interviewer and the respondent. In addition the standard boards were found to be too large and were difficult to operate. The substantive change made to the SG board during the course of the piloting was the use of a sliding scale rather than a wheel, and a new TTO board was designed so that both sides could be used – one for states considered better than death, and the other for states considered worse than death. A fundamental question arising from the pilot work was the advantage of using props such as boards and cards in the interview. To address this issue, an alternative method of administering the SG and TTO tasks was developed representing a significant departure from the standard methodology. In these modified procedures, the respondent was able to take a much more active role and in fact completed much of the valuation task by him/herself without the use of a board. All four methods performed very well in the main study, to the extent that no single method proved decisively superior to all others from an administrative point of view. Ultimately the choice of method was based on empirical grounds, with the result that the TTO ‘Props’ (with board and cards) was selected as the ‘best’ method for valuing health states in population surveys. Although the MVH Group is now concentrating on the TTO ‘Props’ method in further work, there are certain to be other researchers who want to use the SG method or the TTO in its self-completion form. Thud we want to ensure that all our methods are available to other interested parties in the field of health status measurement. The health states used in this study were based on the EuroQol descriptive system (kind et al, 1994), but these valuation procedures have a general application and can be used for any health state descriptive system. Being aware of the considerable work required in designing and piloting any new methods, we felt that it would be useful if other researchers were able to gain access to a detailed account of the procedures that we had developed. In order to maximise the availability of these designs, we have decided to supplement the initial report describing the piloting and interview design (Thomas and Thomson, 1992) with specific User Guides detailing the four valuation methods. Standard Gamble: Props and Self-completion Time Trade-Off: Props and Self-completion Revisions to the TTO Props method as a result of more recent survey work have also been included. We hope others will be able to pick up from where we have left off, either to make use of the methods in their current form or to modify them further as they wish. In either event we look forward to interest to hearing of the results.Standard Gamble, DG, health states

Time trade-off user manual: props and self-completion methods

In 1992, the Measurement and Valuation of Health (MVH) Group at the Centre for Health Economics conducted a study with Social and Community Planning Research (SCPR) comparing different methods of valuing health states (Dolan et al, 1993). A random sample of 335 members of the general population were interviewed in their own homes by specially trained interviewers. Each respondent was asked to value a series of health states using two different valuation methods – Standard Gamble (SG) and Time Trade-Off (TTO). Considerable time and energy went into the production of the protocols for the interviews. Standard methodology (derived primarily from research in Canada and the USA) for both the SG and TTO methods involves the use of specially designed boards and cards. He SG procedure typically uses a ‘probability wheel’ which allows different probabilities of health outcomes to be presented to the respondent, while the TTO typically uses a horizontal sliding scale which allows the length of time spent in a health state to be varied. SG and TTO boards based on the standard methodology were piloted as part of the MVH study and it was found that substantial modifications were required to simplify the material for both the interviewer and the respondent. In addition the standard boards were found to be too large and were difficult to operate. The substantive change made to the SG board during the course of the piloting was the use of a sliding scale rather than a wheel, and a new TTO board was designed so that both sides could be used – one for states considered better than death, and the other for states considered worse than death. A fundamental question arising from the pilot work was the advantage of using props such as boards and cards in the interview. To address this issue, an alternative method of administering the SG and TTO tasks was developed representing a significant departure from the standard methodology. In these modified procedures, the respondent was able to take a much more active role and in fact completed much of the valuation task by him/herself without the use of a board. All four methods performed very well in the main study, to the extent that no single method proved decisively superior to all others from an administrative point of view. Ultimately the choice of method was based on empirical grounds, with the result that the TTO ‘Props’ (with board and cards) was selected as the ‘best’ method for valuing health states in population surveys. Although the MVH Group is now concentrating on the TTO ‘Props’ method in further work, there are certain to be other researchers who want to use the SG method or the TTO in its self-completion form. Thud we want to ensure that all our methods are available to other interested parties in the field of health status measurement. The health states used in this study were based on the EuroQol descriptive system (kind et al, 1994), but these valuation procedures have a general application and can be used for any health state descriptive system. Being aware of the considerable work required in designing and piloting any new methods, we felt that it would be useful if other researchers were able to gain access to a detailed account of the procedures that we had developed. In order to maximise the availability of these designs, we have decided to supplement the initial report describing the piloting and interview design (Thomas and Thomson, 1992) with specific User Guides detailing the four valuation methods. Standard Gamble: Props and Self-completion Time Trade-Off: Props and Self-completion Revisions to the TTO Props method as a result of more recent survey work have also been included. We hope others will be able to pick up from where we have left off, either to make use of the methods in their current form or to modify them further as they wish. In either event we look forward to interest to hearing of the results.time trade-off, TTO, MVH Group

Consequences from use of reminiscence - a randomised intervention study in ten Danish nursing homes

<p>Abstract</p> <p>Background</p> <p>Reminiscence is the systematic use of memories and recollections to strengthen self-identity and self-worth. The study aim was to investigate the consequences for nursing home residents and staff of integrating reminiscence into daily nursing care.</p> <p>Methods</p> <p>In this randomised study, ten nursing homes were matched into two groups on the basis of location, type and size. In the period August 2006 - August 2007, staff in the Intervention Group were trained and supported in the use of reminiscence, involving individual and group sessions with residents as well as reminiscence boxes, posters and exhibitions. At baseline and again 6 and 12 months after the intervention start, data were collected on residents' cognitive level, agitated behaviour, general functioning and proxy-assessed quality of life, as well as on staff well-being and job satisfaction. Mixed linear modelling was used to analyse differences in outcome between the intervention and control groups.</p> <p>Results</p> <p>Project drop-out rates were 32% for residents and 38% for nursing staff. Most staff in the Intervention Group considered reminiscence a useful tool that improved their communication with residents, and that they would recommend to other nursing homes. There were no significant differences between residents in the Intervention and the Control Group in cognitive level, agitated behaviour or general functioning. Residents in the Intervention Group showed significant higher score at 6 months in quality of life subscale 'Response to surroundings', but there was no significant difference at 12 months.</p> <p>Positive effects of reminiscence were observed for all staff outcome measures, the only exception being SF-12 self-rated physical health. At 6 months after start of reminiscence, staff in the Intervention Group had significantly better scores than those in the Control Group for Personal accomplishment, Emotional exhaustion, Depersonalisation, 'Attitude towards individual contact with residents' and SF-12 self-rated mental health. At 12 months after start of reminiscence, staff in the Intervention Group had significantly better scores than those in the Control Group for Emotional exhaustion and 'Professional role and development'.</p> <p>Conclusions</p> <p>The use of reminiscence appeared to have little long-term effect on the nursing home residents. Nursing staff in the Intervention Group experienced greater satisfaction with professional roles and developed a more positive view of the residents.</p> <p><b>International Standard Randomised Controlled Trial Number Register: ISRCTN90253170</b>.</p

Public versus patient health preferences:protocol for a study to elicit EQ-5D-5L health state valuations for patients who have survived a stay in intensive care

INTRODUCTION: The value set used when calculating quality-adjusted life-years (QALYs) is most often based on stated preference data elicited from a representative sample of the general population. However, having a severe disease may alter a person’s health preferences, which may imply that, for some patient groups, experienced QALYs may differ from those that are estimated via standard methods. This study aims to model 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) valuations based on preferences elicited from a sample of patients who have survived a stay in a Danish intensive care unit (ICU) and to compare these with the preferences of the general population. Further, the heterogeneity in the ICU patients’ preferences will be investigated. METHODS AND ANALYSIS: This valuation study will elicit EQ-5D-5L health state preferences from a sample of 300 respondents enrolled in two randomised controlled trials at Danish ICUs. Patients’ preferences will be elicited using composite time trade-off based on the EuroQol Valuation Technology, the same as that used to generate the EQ-5D-5L value set for the Danish general population. The patient-based and the public-based EQ-5D-5L valuations will be compared. Potential underlying determinants of the ICU preferences will be investigated through analyses of demographic characteristics, time since the ICU stay, self-reported health, willingness to trade-off length of life for quality of life, health state reference dependency and EQ-5D dimensions that patients have experienced themselves during their illness. ETHICS AND DISSEMINATION: Under Danish regulations, ethical approval is not required for studies of this type. Written informed consent will be obtained from all patients. The study results will be published in peer-reviewed scientific journals and presented at national and international conferences. The modelling algorithms will be publicly available for statistical software, such as Stata and R

The HMQ: measuring health status in the community

The measurement of health outcome is central to the evaluation of medical treatment and intervention. In the past, such measurement has been based on data relating to survival and life expectancy. There is now general acknowledgment that a through assessment of the benefits of health care must examine the quality of life, as well as its quantity. The Health Measurement Questionnaire (HMQ) has been developed as a way of collecting self-report information from which a disability/distress rating could be derived on the Rosser Classification of Illness States. This discussion paper provides a fuller review of the data collected as part of a general population survey in which the HMQ was used as a self-report measure of health status alongside the GHQ and the NHP. The HMQ appears to have both construct and convergent validity. It has also discriminated between groups of the population which differ in terms of health status or in the degree of psychiatric morbidity. Several factors have been shown to contribute to overall distress, particularly pain, sadness/depression and dependence on others. It is evident that there is considerable morbidity in the community. These data reinforce the need for continued measurement of health status within the general population, with the dual aim of identifying areas of need, and then monitoring improvement as services are adjusted to meet that need.Health Measurement Questionnaire, HMQ, Rosser rating, disability, distress

The QALY toolkit

QALYs (quality adjusted life years) represent a powerful addition to the range of evaluative techniques for use in assessing the impact of health care. In the past, such benefits have been portrayed in terms of their contribution to life expectancy. The ability to adjust for quality of life is an important step which permits comparisons to be made between specific forms of intervention, and between competing programmes of health care. The measurement of quality of life is fundamental to the calculation of QALYs and is achieved, in this case, by using an index first described by Rachel Rosser (now Professor of Psychiatry, Middlesex Hospital, London). This “toolkit” brings together all the relevant background information on measuring QALYs. The Paper sets out the background to the Rosser index, including both the descriptive classification of disability/distress states and their associated valuations. It also presents examples of the methods which have been used to compute QALYs – by reprocessing published data and consulting specialist reference groups. A self-completed questionnaire which yields Rosser ratings has been developed by the York QALY team for use in survey settings. The questionnaire is included as an Appendix, together with instructions in encoding response data. Policy choice has to be informed by data about the costs and outcomes of therapies and programmes competing for scarce and limited resources. This QALY toolkit, in conjunction with cost data, will enable policy makers to identify cost-effective policies and ensure choices give good value for money to public and private sector health care systems.QALY