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Blog. Sense Ecology is een duurzaam en praktijkgerciht kunst-onderzoeksproject. Het project onderzoekt alternatieve manieren om het landschap te ervaren, en onderzoekt en ontwikkelt nieuwe methoden en hulpmiddelen voor biodiversiteitsonderzoek. Sense Ecology ontwerpt en ondersteund projecten die zich richten op zintuigelijke waarneming van de natuurlijke omgeving.

GRADE ("Grading of Recommendations Assessment, Development and Evaluation") provides a transparent framework to evaluate scientific evidence and to develop healthcare recommendations. The GRADE method has been further developed, its application has been significantly broadened and over 100 organizations have endorsed GRADE. In this article, we give an overview of the most important methodological developments and discuss the basic principles. The transparent approach to make it easier for users of evidence to assess the judgments behind recommendations is not only applicable to the EBM domains but also to other disciplines. The methods developments show that GRADE is still evolving, and is constantly being further developed based on the latest methodological insights and users perspective. GRADE is not an instrument to determine the "true" certainty of the evidence. The value of applying GRADE is that judgments about the quality of evidence and the considerations behind recommendations are structured, transparent and explicit.

Although it is generally known that a (statistical) association between a factor, i.e., determinant or independent variable, and outcome, i.e., dependent variable, does not directly provide evidence of a causal relation, in practice the distinction between associative and causal relationships often becomes fuzzy when interpreting prognostic factor research. We provide suggestions for interpreting the findings of prognostic factor research. It is important to assess the purpose and design of the study, including the statistical analysis. The actual evidence that prognostic factor research can provide is easily overestimated. In particular when associations between factors and outcome are estimated in a multivariable analysis, causal or predictive qualities can easily but wrongfully be attributed to a prognostic factor. It is generally advisable to refrain from judgments on the causal of predictive qualities of a prognostic factor purely based on a prognostic factor study. Findings from prognostic factor research are usually a good starting point for follow-up research, while the direct applicability of such findings in daily medical practice is often limited.

Shawn Shea's Chronological Assessment of Suicide Events (CASE approach) is worldwide, including the Netherlands, a well-known and widely used method for clinical interviewing a patient's suicidal state. However, the original description of the author is not always followed.Comparing the Dutch CASE approach with the original description.The Dutch CASE approach has been explored on the basis of the text of the Dutch multidisciplinary guideline and current handbooks. This approach is compared with the original description.Three differences emerge. The main difference is that in the original CASE approach, seven validity techniques represent the foundation for investigation the suicidal state, while these are missing from the Dutch texts. Second, the chronological interview system in the Netherlands is interpreted differently than in the original CASE approach. Third, in the Netherlands, in contrast to the original approach, risk factors and protective factors are included in the study of the suicidal state.In the Netherlands, the CASE approach has been adopted in a simplified form, which is useful as a basic skill in the study of suicidal behavior. The diagnosis of suicidality can gain in depth, especially for advanced mental health professionals, by paying attention in training and education to the interviewing techniques of the original CASE approach.

Calamity investigations often lead to recommendations that are difficult to implement and that are of little relevance, because the analysis is carried out according to a cause and effect system. The complexity of care provision requires a different method that respects the complexity of day-to-day care and is able to assess it correctly. Research according to the Safety-II philosophy clearly shows the variable interactions and dependencies present in daily work. These investigations require more effort and time, but lead to better recommendations, better recognition among professionals and an appreciative way of interviewing. This is to the satisfaction of calamity investigators, involved professionals and patients and family. This method of investigation requires an investment in time and people of the healthcare institution.

Cryobiopsy is an endobronchial technique to obtain peripheral lung biopsies with the use of a flexible bronchoscopic cryo probe. This technique can be used to diagnose diffuse lung diseases when histological evidence is required. This new technique was used for the first time in 2009 and in 2014 we introduced this new method in the Netherlands at the CWZ in Nijmegen. This piece outlines our experiences with Transbronchial lung cryobiopsy (TBLC).

BACKGROUND Negative symptoms hamper treatment progress of patients with schizophrenia. AIM This study evaluates the effect of a music therapy module on negative symptoms, composed of activating music therapy as usual, augmented by elements of neurologic music therapy on negative symptoms. METHOD A pre- and posttreatment measurement with the Dutch version of the Brief Negative Symptom Scale has been taken from five forensic psychiatric patients and their personal nurses. During the module, sociotherapist scored the Negative Symptom Scale three times a week. Applying the reliable change index and simulation modeling analysis, the quantitative change in negative symptoms was analyzed for each patient, supported by a qualitative analysis of the medical files. RESULTS Four out of five patients showed reduction in negative symptoms. CONCLUSION Music therapy seems to have a positive effect on the reduction of negative symptoms and regaining of activity and treatment motivation in forensic psychiatric patients, who prior to the study were long-lasting inactive and difficult to motivate. Adjusting the music therapy to individual needs, personalized treatment, is in line with the complexity of the target group.

Research into diagnostic reasoning often focuses on diagnostic errors, while ignoring the also important concepts of overdiagnosis and cost of the diagnostic process. A popular theoretic model guiding studies on the subject is the dual process model in which cognitive errors play an important role. This paradigm is also used in the study of Mamede and colleagues, who studied the effect of disease specific knowledge on the occurrence of diagnostic errors due to availability bias in internal medicine residents. The study, which used case vignettes, is well set up but its experimental design cannot account for the influence of clinical context which limits its clinical value. Further research into this topic should be performed in actual clinical situations to provide more insight in how to improve diagnostic reasoning in medicine.

The flash mob method is a new way of conducting prospective research whereby relatively simple - but clinically relevant - questions can be answered in a short period of time. The design and intensity of the spirited action - the 'flash' - with which the research is initiated determines the size of the group - the 'mob' - of researchers who will collect research data, and therefore determine the size of the study population. The reach of a flash mob study differs from that of traditional studies and gives flash mob studies a special character. In this article we show how the flash mob method works, the opportunities that it presents, its limitations and the kinds of questions it is able to answer.

Various studies suggest that evening dosing of antihypertensive drugs may be more effective. In line, a randomized open-label trial in 19,084 hypertensive patients recently demonstrated that evening dosing of at least one antihypertensive drug resulted in a 3.3 mmHg lower systolic night-time blood pressure and 1.3 mmHg lower systolic 48-hour blood pressure when compared to morning dosing. Cardiovascular outcomes were reduced by 45% in the evening dosing group, which is remarkable as previous meta-analyses have shown that a systolic blood pressure reduction of 3 mmHg is associated with a 7% reduction in cardiovascular outcome. Although this discrepancy may be partly explained by specific beneficial effects related to evening dosing, it is likely that the open-label trial design may have affected the study outcome in different ways. Also, the safety of evening dosing in elderly hypertensive patients and the consequences for therapy compliance in the clinical setting remain to be established.

A large population-based cohort study by Gharbi et al. found an association between deferred or no antibiotic prescribing in patients with a urinary tract infection (UTI) or suspected UTI and an increased incidence of bloodstream infections and all-cause mortality. The study concludes that early initiation of antibiotics in (high risk) elderly is recommended. This contradicts with recently adjusted guidelines for UTI infections in elderly, in which clinicians are encouraged to be prudent with the prescription of antibiotics in order to avoid over-treatment. Critical appraisal of the study, however, reveals several arguments that challenge the clinical relevance of the findings; a nuanced interpretation of this study's conclusion is therefore indicated. Altogether, current guidelines for elderly with UTI provide sufficient standards for safe care, since they emphasize that holding back antibiotics should be combined with a careful watchful waiting policy and adequate safety net advice.

In medical educational research specific approaches and research methods are used, the risk being that the field becomes less accessible to clinicians and teachers.br/AIM: To highlight the relevance of educational research for clinical practice.br/METHOD: A description of the development of medical educational research as a field and of the different types of research questions and the role of theories from related social sciences such as psychology, pedagogy and sociology.br/RESULTS: First, there are the descriptive studies, based on the question 'what has been done'. Second, there are justification studies that compare educational innovations with existing practice to provide insight into 'did the intervention work better?'. A third group of studies focuses on clarification of underlying learning processes, with the question 'why or how did it work?' Theory helps with the design of studies and interpretation of research results, thereby increasing the quality and relevance of medical educational research.br/CONCLUSION: Medical educational research has developed rapidly, and the involvement of teachers and clinicians (such as psychiatrists) is necessary to ensure that it remains closely connected to practice.

Many readers of medical journals are trained in the 'quantitative approach'. This can therefore lead to the misinterpretation of results from qualitative research. By considering four key points, readers can interpret a qualitative paper. The chosen research method should fit the research question. Within medicine, the most common types of qualitative research are: (a) in-depth interviews, (b) focus groups, (c) participating observation, and (d) document analysis. The researchers should sufficiently describe their own role in the study. The results should be illustrated with quotes from study participants. The research should be conducted in a technically correct manner. Certain characteristics will highlight this, such as iterative data collection and saturation, the latter meaning that data collection was discontinued when no new insights or themes were identified anymore. The conclusion should be drawn from results obtained within the study. A common error made by researchers is to interpret the results from a qualitative study in a quantitative manner.

In randomised trials on the effects of a medical treatment, the power of the trial corresponds to the conditional probability that the conclusion of the trial will be that the treatment is effective, given a certain treatment effect.- The time to consider the power of a trial is before conducting the study, to ensure that the design of the trial is such that there is a reasonable chance of demonstrating a clinically relevant effect.

The randomised placebo-controlled trial (RCT) is the gold standard for the evaluation of medical interventions. Observational studies, on the other hand, usually do not get much credit. For studies investigating surgical interventions this does not always seem entirely justified. A more refined approach might be needed for the often-used hierarchical structure of research designs. Instead of a strict separation of results from RCTs and other designs, results of the different designs should rather be regarded as complementary to each other when evaluating surgical interventions in traumatology.

The care for frail elderly is challenging and requires an individualised approach. To meet the complex care needs of these patients, interventions aimed at improving care often consist of multiple interacting components. Several recent RCTs investigating such complex interventions in a primary care setting were unable to show an effect. In this paper the challenges that arise when examining complex interventions in experimental trials are discussed. Standardisation of the content of the intervention is often not desirable. The context in which the intervention takes place cannot be controlled and is in itself complex. A thorough process evaluation is essential in order to interpret the findings correctly. The relevant outcomes in such trials are often multidimensional and difficult to capture with a quantitative instrument. Such complex interventions, therefore, require a combination of quantitative and qualitative research methods.

Older persons represent a growing proportion of the population. However, few of them participate in medical research. Moreover, amendments have been proposed to the Medical Research Involving Human Subjects Act (WMO) concerning the participation of vulnerable subjects such as older persons. In light of these changes, the Dutch Ministry of Health, Welfare and Sport sought to develop a guideline to improve the quality of research involving older persons. This guideline will also be a tool for researchers to enhance the inclusion of older persons in their medical research. It focuses on six aspects to consider when setting up a research project: recruitment, informed consent, attrition, reluctance to participate, proportionality between the burden for participants and the benefits for the investigator, and societal relevance.

Keeping up with the latest developments is not easy, but neither is reading articles on research. There are too many medical journals that contain information that is irrelevant to clinical practice. From this mass of articles you have to decide which are important for your own clinical practice and which are not. Most articles naturally fall into the latter category as spectacular findings with important consequences for medical practice do not occur every week. The most important thing in a research article is the research question. If you begin with this, then you can put aside much scientific literature. The methodology section is essential; reading this can save you a lot of time. In this article we take you step-by-step through the process of reading research articles. The articles in our Methodology series can be used as background information. These articles have been combined in a tablet app, which is available via www.ntvg.nl/methodologie.

All critically ill children admitted to a paediatric intensive care unit (PICU) receive drug treatment. However, the majority of these drugs has never been tested in these children, and their safety and efficacy have not been proven. Clinical drug research is therefore required in this patient group. While doing this research we need to balance between the advancement of knowledge--and thereby potential improvements in clinical care--and protection of a vulnerable population against harm and exploitation. The PICU environment and the vulnerable population raise specific ethical challenges and mean that the research should be designed and conducted with care. The ethical challenges are related to 4 areas: a) study design and conduct; b) informed consent from parents and children; c) burden and risk for the child; and d) research or experimental treatment. These challenges and possible solutions will be discussed in this article.

This thesis explores how a meaningful relation between theory and practice in teacher education can be established/created. To that end a four-year curriculum and instructional design was developed, evaluated and implemented in a design research project.

Universities do not come up to a growing demand for practice oriented research and for students trained in this type of activity. Existing methodology mainly is theory oriented. We in large part miss methodology for producing prescriptive knowledge, for a holistic approach and for design oriented research. As to the education of students in research methodology, besides the deficiencies just mentioned, too much attention is given to data analysis and statistics. As a consequence designing research is underexposed. Students should learn to analyse the problem to be solved, translating it into adequate research questions, making a taxonomy of the main concepts and making them operational, reducing the research to a feasible size, and developing a detailed and efficient plan for the generation of the research material. All this is far more complex for a beginning researcher than generally is understood.

For new interventions, the results of sequential randomized or non-randomized trials and meta-analysis can differ significantly. Evaluation of the evidence for the effect of a new treatment is a complex interplay of several factors, including the methodological design, the risk of a coincidental finding and applicability in practice. For proper appraisal of the design of trials, the use of aggregate scores should be avoided and individual study limitations should be mentioned. With the use of additional analyses we can now test whether meta-analyses contain sufficient data to find potentially relevant differences. The new 'Grading of recommendations assessment, development and evaluation' (GRADE) system is a consensus guideline that combines multiple factors into an easily interpreted judgment of the strength of evidence. Concise presentation of important quality factors for each outcome significantly increases clarity. A more realistic assessment of the reliability of the evidence decreases the risk of major fluctuations in treatment policy.

Dementia care in The Netherlands is shifting from fragmented, ad hoc care to more coordinated and personalized care. Case management contributes to this shift. The linkage model and a combination of intensive case management and joint agency care models were selected based on their emerging prominence in The Netherlands. It is unclear if these different forms of case management are more effective than usual care in improving or preserving the functioning and well-being at the patient and caregiver level and at the societal cost.The objective of this article is to describe the design of a study comparing these two case management care models against usual care. Clinical and cost outcomes are investigated while care processes and the facilitators and barriers for implementation of these models are considered.Mixed methods include a prospective, observational, controlled, cohort study among persons with dementia and their primary informal caregiver in regions of The Netherlands with and without case management including a qualitative process evaluation. Community-dwelling individuals with a dementia diagnosis with an informal caregiver are included. The primary outcome measure is the Neuropsychiatric Inventory for the people with dementia and the General Health Questionnaire for their caregivers. Costs are measured from a societal perspective. Semi-structured interviews with stakeholders based on the theoretical model of adaptive implementation are planned.521 pairs of persons with dementia and their primary informal caregiver were included and are followed over two years. In the linked model substantially more impeding factors for implementation were identified compared with the model.This article describes the design of an evaluation study of two case management models along with clinical and economic data from persons with dementia and caregivers. The impeding and facilitating factors differed substantially between the two models. Further results on cost-effectiveness are expected by the beginning of 2015. This is a Dutch adaptation of MacNeil Vroomen et al., Comparing Dutch case management care models for people with dementia and their caregivers: The design of the COMPAS study.

In a meta-analysis results of different studies are summarized quantitatively. This gives a much more precise effect estimate than is possible in individual studies. Prior to the analysis, all relevant studies should be traced, including studies with less favourable results. Exclusion of 'negative' studies may lead to overestimation of the effect. Because the results of a meta-analysis depend on the quality of the included studies, the quality and risk of bias of all studies should be systematically assessed. Quantitative summary of results is only practicable if the studies are homogeneous, i.e. sufficiently similar with respect to the study populations, interventions or exposure, outcomes and point of measurement. In cases of clinical heterogeneity, meta-analysis could be conducted in clinically homogeneous subgroups. Statistical heterogeneity can be discounted by using a random-effects model. Meta-analyses can be applied to research questions regarding aetiology, diagnosis, treatment or prognosis.

To gain an insight into the costs and health outcomes of effectiveness studies in obstetrics at a national level.Budget impact analysis.We searched for obstetric effectiveness studies. The possible budget impact of implementation in all patients in the Netherlands was calculated, as well as health benefits for mothers and their children.We used eight multicentre randomized trials with almost 11,000 patients in total. The total potential cost reduction for these trials was € 9.6 million per year, on the basis of a one-time investment in the trials of € 3.1 million. When implementing the results of these studies, a health benefit is shown in women with hypertension or pre-eclampsia at term, women in whom labour is induced and women with fetal monitoring. This also applied to the children of these women. Furthermore, removal or non-implementation of interventions that have no positive effect on health such as prolonged tocolysis, the use of progestogens in twin pregnancies, intrauterine pressure catheters, and induction of labour in preterm ruptured membranes reduces care costs.Adequate application of the results of effectiveness studies in obstetrics should result in considerable health gains and cost reduction when compared with provision of non-scientifically supported care.

An intermediate variable such as blood pressure is part of the causal pathway of mechanisms to a clinical outcome, e.g. myocardial infarction. An intervention affects a clinical outcome through its effect on that intermediate variable. In studies designed to assess the effects of interventions an intermediate variable may be used as surrogate for clinical outcomes. Such an endpoint is also known as an intermediate endpoint. Intervention studies with intermediate endpoints are commonly performed in medical research to evaluate the effects of an intervention on clinical outcomes. Intervention studies with an intermediate endpoint are conducted in a smaller study population and with a shorter duration of follow-up than studies using clinical outcomes. An intermediate variable is not eligible as an intermediate endpoint when the intervention also affects other biological mechanisms that subsequently affect the clinical endpoint. Due to a smaller sample size and shorter study duration, side effects of intervention are more difficult to evaluate in studies with an intermediate endpoint than in studies with clinical endpoints.

To evaluate whether the speed at which multicenter studies can be launched in the Netherlands has been improved by the new External Review Directive.Cohort study.We studied the time between requesting and granting a declaration of local feasibility of 7 multicenter studies under the new External Review Directive, which came into effect on 1 March 2012. We distinguished between centres that complied with the new directive and those that did not. We also compared the time to approval of local feasibility of these 7 studies with those of 13 studies that were launched under the old directive.Under the new procedure, the median time between issue of the approval letter by the primary evaluative centre and approval by the Board of Directors of the participating centre was 93 days: 50 days for centres that performed the procedure in accordance with the directive (31 applications) and 118 days for centres that did not perform the review in accordance with the new directive (79 applications). This difference was significant (log rank test; p = 0.003). Under the old procedure, the median time to approval was 103 days (336 applications).The new External Review Directive for multicenter studies provides a significant improvement in time to approval of local feasibility for multicenter trials in centres that commit to the new directive. However, the majority of hospitals have not yet complied with this directive, which still delays studies unnecessarily.

In medical research missing data are sometimes inevitable. Different missingness mechanisms can be distinguished: (a) missing completely at random; (b) missing by design; (c) missing at random, and (d) missing not at random. If participants with missing data are excluded from statistical analyses, this can lead to biased study results and loss of statistical power. Imputation methods can be applied to estimate missing values; multiple imputation gives a good idea of the inaccuracy of the reconstructed measurements. The most common imputation methods assume that missing data are missing at random. Multiple imputation contributes greatly to the efficiency and reliability of estimates because maximum use is made of the data collected. Imputation is not meant to obviate low-quality data.

The standard randomized controlled trial (RCT) does not appear to be the most suitable design for the fast and efficient simultaneous evaluation of multiple interventions for the same condition. The cohort multiple randomized controlled trial (cmRCT) design offers the opportunity to perform randomized trials for multiple interventions simultaneously and is a promising alternative for the classic RCT. The basis of the cmRCT is an observational cohort of patients with the same condition. The patients will generally undergo standard treatment. The patient characteristics are captured at baseline and outcome measures are captured at fixed points of time. Eligible patients within the observational cohort are identified for each new intervention, some of whom will be randomly selected and offered the new intervention. The other eligible patients will not be approached and will undergo the standard treatment. The same process can be simultaneously repeated for other interventions. Advantages include the ability to facilitate multiple simultaneous randomized evaluations, the improved comparability between trials and the patient-centered informed consent procedure.

Despite well-known differences in drug response between children and adults, dosing guidelines for children are usually developed by extrapolating the results from studies in adults. Instead of body weight, insight into the pharmacokinetics and pharmacodynamics of drugs should serve as the basis for dosing in children. In studies into drug dosing in children, the 'population approach' should be chosen to minimize the burden for the child. With a population approach, the covariates that affect the pharmacokinetics and pharmacodynamics of drugs can be identified in a covariate analysis; examples of covariates include body weight, age, degree of illness and genetic factors. Drugs that serve as a model for a specific elimination route provide the basis for individualized dosing guidelines for children.

There are ethical and economic reasons to design and conduct medical research as efficiently as possible. Clinical trials often take a long time because of the number of patients that must be included and the follow-up time in the study. Many data already become available during that time. By making interim analyses of these data it is possible to decide whether a final conclusion can be made. This may save time and may lead to a reduction in the number of patients. The statistical methodology of interim analyses is more complex than a fixed sample analysis and must be planned carefully in advance. The most important methods are sequential analysis and group sequential analysis. Both methods are aimed at a low risk of a false-positive conclusion. In this article we explain the application of these methods as well as considerations in the design of a study and interpretation of the results.

Randomized, parallel group clinical trials often require large groups of patients; this is expensive and takes time. A randomized cross-over trial can be an efficient and more affordable alternative. A cross-over design can be used to study chronic disorders in which treatments have temporary effects. Participants receive all treatments in consecutive periods and outcomes are measured after every period. In general, only a quarter of the total group size is needed for cross-over studies compared with parallel group studies. Results can be affected by period-effects and carry-over-effects, which can be prevented through randomization and a wash-out period of sufficient length. The dropping-out of participants has more negative consequences for cross-over studies than for parallel group studies.

The aim of non-inferiority trials is to show that a new treatment is not less effective than standard treatment, in other words 'non-inferior'. The non-inferiority margin should be determined before a study commences. This margin determines the maximal magnitude of difference in effectiveness permissible if it is to be concluded that a new treatment is not less effective than the standard treatment. There is usually a good reason for a non-inferiority design. For example, because the new treatment is easier to use, provides better cost-effectiveness or has fewer side effects. The reader of a non-inferiority trial should consider a number of aspects critically: (a) the reason for use of this study design, (b) the assumed benefit of the new treatment, (c) the rationale for the choice of non-inferiority margin and (d) the choice of the standard therapy with which the new treatment is compared.

The volume of our brain decreases as we age. This has been demonstrated by several large studies on normal aging. A recent study indicates, however, that the extent of this decline in normal aging probably has been overestimated because these studies have included subjects with preclinical disorders. In this article, an example from science is used to describe what effect selection bias may have on our model of the aging brain.