Shifting climatic responses of tree rings and NDVI along environmental gradients.

Variations in the growth of aboveground biomass compartments such as tree stem and foliage significantly influence the carbon cycle of forest ecosystems. Yet the patterns of climate-driven responses of stem and foliage and their modulating factors remain poorly understood. In this study, we investigate the climatic response of Norway spruce (Picea abies) at 138 sites covering wide spatial and site fertility gradients in temperate forests in Central Europe.

Ecological and methodological drivers of non-stationarity in tree growth response to climate.

Radial tree growth is sensitive to environmental conditions, making observed growth increments an important indicator of climate change effects on forest growth. However, unprecedented climate variability could lead to non-stationarity, that is, a decoupling of tree growth responses from climate over time, potentially inducing biases in climate reconstructions and forest growth projections. Little is known about whether and to what extent environmental conditions, species, and model type and resolution affect the occurrence and magnitude of non-stationarity.

Estimating Snow Depth and Leaf Area Index Based on UAV Digital Photogrammetry.

This study presents a novel approach in the application of Unmanned Aerial Vehicle (UAV) imaging for the conjoint assessment of the snow depth and winter leaf area index (LAI), a structural property of vegetation, affecting the snow accumulation and snowmelt. The snow depth estimation, based on a multi-temporal set of high-resolution digital surface models (DSMs) of snow-free and of snow-covered conditions, taken in a partially healthy to insect-induced Norway spruce forest and meadow coverage area within the Šumava National Park (Šumava NP) in the Czech Republic, was assessed over a winter season. The UAV-derived DSMs featured a resolution of 0.

Evidence and its uses in health care and research: the role of critical thinking.

Obtaining and critically appraising evidence is clearly not enough to make better decisions in clinical care. The evidence should be linked to the clinician's expertise, the patient's individual circumstances (including values and preferences), and clinical context and settings. We propose critical thinking and decision-making as the tools for making that link.

No surgical innovation without evaluation: the IDEAL recommendations.

Surgery and other invasive therapies are complex interventions, the assessment of which is challenged by factors that depend on operator, team, and setting, such as learning curves, quality variations, and perception of equipoise. We propose recommendations for the assessment of surgery based on a five-stage description of the surgical development process. We also encourage the widespread use of prospective databases and registries.

Challenges in evaluating surgical innovation.

Research on surgical interventions is associated with several methodological and practical challenges of which few, if any, apply only to surgery. However, surgical evaluation is especially demanding because many of these challenges coincide. In this report, the second of three on surgical innovation and evaluation, we discuss obstacles related to the study design of randomised controlled trials and non-randomised studies assessing surgical interventions.

Evaluation and stages of surgical innovations.

Surgical innovation is an important part of surgical practice. Its assessment is complex because of idiosyncrasies related to surgical practice, but necessary so that introduction and adoption of surgical innovations can derive from evidence-based principles rather than trial and error. A regulatory framework is also desirable to protect patients against the potential harms of any novel procedure.

Clinical case reports and case series research in evaluating surgery. Part II. The content and form: uses of single clinical case reports and case series research in surgical specialties.

Single clinical case and case series reports have long been an integral part of medicine and surgery. Despite this, due to their vague objectives and questions to answer, unstructured presentations and absent, exaggerated and/or unsubstantiated conclusions and recommendations, they are sometimes perceived as a lighter piece of evidence in modern surgical understanding and decision-making. Their value may, in fact, be in their contribution to theory, inference, or both.

Clinical case reports and case series research in evaluating surgery. Part I. The context: general aspects of evaluation applied to surgery.

The relevance, structure, focus, form, and content of modern clinical case reporting and case series research may be seen and understood only in the context of evaluation in medicine and surgery today. The benefits and effectiveness of surgery remain at the core of evaluation in surgery. Surgical errors evaluation is an increasingly important topic give their impact on patients and human and material resources in medicine and surgery and social and community implications.

Evidence-based medicine: fifteen years later. Golem the good, the bad, and the ugly in need of a review?

Despite its well-deserved strengths, Evidence-Based Medicine (EBM)'s shell still remains half-full. Its strong points are clouded in persisting philosophical gaps and mostly ideological advancements of its concepts and rules. Further clarification of its logic and critical use of evidence is required.

The hard art of soft science: Evidence-Based Medicine, Reasoned Medicine or both?

In the past 14 years, Evidence-Based Medicine (EBM) has enjoyed unprecedented developments and gained widespread acceptance among health professionals. However, should we be content with producing, critically appraising and using the best evidence available for our understanding of health problems and decision making about them? Are our convictions about EBM's relevance, our conviction and intellectual satisfaction with its mastery and adoption enough? Should we continue pushing forward along this promising path, or should we further diversify the content and scope of EBM? Is EBM the only way to view medicine in the near future? This paper presents some options to choose from in terms of direction and content as well as questions to answer given the current EBM crossroads. More intensive and extensive EBM combined with 'other features'-based medicines may be the preferred strategy to follow in the future to determine the development, use and evaluation of EBM.

Towards evidence-based critical thinking medicine? Uses of best evidence in flawless argumentations.

Uses of informal logic and critical thinking methodology are increasingly taught, learnt and advantageously applied in such diverse domains as law, the military, business, and education. Health sciences are also following this trend. However, production and critical appraisal of evidence as already practiced in Evidence-Based Medicine must be coupled with equally rigorous uses in order to ensure appropriate health problem understanding and decision-making.

How to read, understand, and write 'Discussion' sections in medical articles. An exercise in critical thinking.

Writing and reading 'Discussion' sections in medical articles require a procedure as exact and structured as that involved in raising questions, choosing materials and methods and producing results for a health research study. The medical article as a whole can be considered an exercise in modern argumentation and its 'Discussion' section, a systematic critical appraisal of a path from theses to conclusions. The methodology of modern critical thinking applies perfectly to article writing, reading, and understanding.

Evidence-based public health, community medicine, preventive care.

The use of evidence-based reasoning and decision-making theory and practice is becoming increasingly commonplace in most of the health sciences. Public health, which encompasses health protection, disease prevention and health promotion, has traditionally been more evidence-based than clinical medicine. However, more must be done to grade evidence in the absence of classical clinical trials or other experimental proof.

Therapy of shock with naloxone: a meta-analysis.

Objectives: To evaluate the effectiveness of naloxone in human shock; and to estimate the methodologic quality of the clinical trials.

Data Sources: Computerized bibliographic search on MEDLINE covering the period from January 1979 to July 1996, review of references of all papers found on the subject, and contact with primary investigators of eligible studies.

Study Selection: To be included in this study, a paper should be a randomized, clinical trial published in a peer-reviewed journal evaluating naloxone in human shock, regardless of the patient's age (adult, child, neonate).

A meta-analytic review of the effect of exercise on smoking cessation.

Objective: To assess the effect of group exercise programs on smoking cessation.

Data Sources: A MEDLINE search, a manual review of journal articles, and a search of previous reviews were used.

Study Selection: Published studies which 1) employed an exercise program for an intervention group and, 2) reported numbers of smokers of both exercise and control groups at baseline and at 6 to 24 months later were selected.

Impact of receiving blood cholesterol test results on dietary change.

Introduction: The study objective was to determine the impact of receiving results of a blood cholesterol test on changes in dietary behaviors among individuals participating in a Health Risk Appraisal Program.

Methods: This randomized trial of maintenance employees at six hospitals included two groups: Group 1 received their blood cholesterol test results at the pretest; Group 2 received results only at the posttest (16-20 weeks later). The pretest interview included (1) a 24-hour dietary recall; (2) an evaluation of dietary behaviors and suggestions on how to change; (3) height, weight, and blood cholesterol measurement.

Epidemiology, evidenced-based medicine, and evidence-based public health.

Evidence-Based Medicine (EBM) is heralded as a new paradigm of medicine. Is it? What is its link to epidemiology? Does an evidence-based (EB) approach apply also to other health sciences and to public health in particular? What has epidemiology already achieved in these domains, and what remains to be done? What should our priorities be in the coming years? The EB approach is essential in all health sciences at two levels: for problem solving, and for decision making. It applies to all health sciences, be it medicine, nursing, public health, or others.

Impact of a false positive blood culture result on the management of febrile children.

Objective: To evaluate the impact of a preliminary positive blood culture result, subsequently confirmed to be a false positive blood culture result on rate of hospitalization, antibiotic therapy and use of microbiologic tests.

Design: Retrospective chart review.

Patients And Methods: Children between 1 month and 18 years old on whom a blood culture was performed were eligible, excluding those with an underlying condition for whom a false positive blood culture may be difficult to assess.

Adjuvant chemotherapy in colorectal carcinoma: results of a meta-analysis.

Unlabelled: Despite the National Institutes of Health consensus regarding use of adjuvant chemotherapy in colorectal carcinoma, many general surgeons question the efficacy of this approach when considering costs involved for both the individual patient and society at large.

Purpose: This study was designed to determine the real impact of adjuvant chemotherapy on five-year survival rates of patients.

Method: A qualitative and quantitative meta-analysis of results from 39 randomized clinical trials published from 1959 to 1993 is described.