Search

Validation is an important topic in the system dynamics field. A large body of knowledge addresses validation tests and procedures. However, the use of validation in practice and its results are scarcely reported. This is surprising as some authors assume that in order to build confidence in a model, it is crucial to at least communicate the validation process and its results. In this paper, we described a validation process in direct interaction with clients. We describe the tests and procedures we employed to iteratively build and validate a simulation model with the National Health Care Institute (The Netherlands) in a group model-building setting. The involvement challenged the clients' opinions and in some cases led to changes in their mental models. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction: The GRADE-ADOLOPMENT methodology has been widely used to adopt, adapt or de novo develop recommendations from existing or new guideline and evidence synthesis efforts. This guidance refines the operationalization for applying GRADE-ADOLOPMENT., Methods: Through iterative discussions, online meetings and email communications, the GRADE-ADOLOPMENT Project Group drafted the updated guidance. We then conducted a review of handbooks of guideline-producing organizations, and a scoping review of published and planned Adolopment guideline projects. The lead authors refined the existing approach based on the scoping review findings and feedback from members of the GRADE Working Group. We presented the revised approach to the group in November 2022 (approximately 115 people), in May 2023 (approximately 100 people) and twice in September 2023 (approximately 60 and 90 people) for approval., Results: This GRADE guidance shows how to effectively and efficiently contextualize recommendations using the GRADE-ADOLOPMENT approach by: (1) showcasing alternative pathways for starting an adolopment effort; (2) elaborating on the different essential steps of this approach, such as building on existing EtDs when available or developing new EtDs if necessary; and (3) providing examples from adolopment case studies to facilitate the application of the approach. We demonstrate how to use contextual evidence to make judgments about EtD criteria, and highlight the importance of making the resulting EtDs available to facilitate adolopment efforts by others., Conclusion: This updated GRADE guidance further operationalizes the application of GRADE-ADOLOPMENT based on over six years of experience. It serves to support uptake and application by end users interested in contextualizing recommendations to a local setting or specific reality in a short period of time or with limited resources., (Copyright © 2024. Published by Elsevier Inc.)

The Dutch Health Care Insurance Board (CVZ) and the Institute for Medical Technology Assessment have developed a questionnaire to help assessors to formulate an answer to the question of which evidence fits best when evaluating the effectiveness of interventions by medical specialists. The Feasible Information Trajectory (FIT) questionnaire is based on the idea that the clinical setting defines the attainable study characteristics and thus possibly available evidence. The FIT questionnaire focuses on study characteristics (randomization, blinding and control groups) and not on study type (e.g. RCT, cohort) as is common within evidence-hierarchy grading systems. Together these attainable characteristics define the most -fitting evidence. The questionnaire should be filled in prior to the literature assessment. Subsequently the most-fitting evidence profile can be modified on the basis of a literature assessment and possibly arguments put forward by healthcare professionals. Filling out the FIT questionnaire is therefore not a static exercise but is part of the search for all relevant arguments in the assessment of effectiveness.

Eleven series of figures were studied, each series ranging from one extreme interpretation via five ambiguous intermediates to a second extreme interpretation. Triplets consisting of an ambiguous exemplar in the middle flanked on the left and right by its two extreme interpretations were presented to large groups of subjects. The initial aim was to establish the levels of perceptual ambiguity of each exemplar in a series, and normative data on the ambiguous figures are provided for future reference and use. However, several biases were encountered and these were examined in more detail. In experiment 1 the subject's task was to compare the middle figure with the flankers and draw an arrow from the middle figure towards the flanking extreme they judged the most similar. Here, an overall preference for the left extreme was found. Therefore the instructions were reversed in experiment 2; flankers had to be compared with the middle figure. The preference for the left extreme remained for figures of living objects, but for nonliving objects the preference switched to the right extreme. To do away with any effect of the arrows, in experiment 3 subjects were divided into two groups each receiving different instructions and were asked to circle one of the extremes. However, the pattern of biases remained the same. The bias found with figures of living objects may be explained on the basis of top-down processes. For nonliving figures, an hypothesis based on bottom-up processes like neural fatigue was considered but rejected.