Definition and terminology of developmental language disorders-Interdisciplinary consensus across German-speaking countries.

In recent years, there have been intense international discussions about the definition and terminology of language disorders in childhood, such as those sparked by the publications of the CATALISE consortium. To address this ongoing debate, a Delphi study was conducted in German-speaking countries. This study consisted of three survey waves and involved over 400 experts from relevant disciplines. As a result, a far-reaching consensus was achieved on essential definition criteria and terminology, presented in 23 statements. The German term 'Sprachentwicklungsstörung' was endorsed to refer to children with significant deviations from typical language development that can negatively impact social interactions, educational progress, and/or social participation and do not occur together with a potentially contributing impairment. A significant deviation from typical language development was defined as a child's scores in standardized test procedures being ≥ 1.5 SD below the mean for children of the same age. The results of this Delphi study provide a proposal for a uniform use of terminology for language disorders in childhood in German-speaking countries.

Reporting guidelines for Delphi techniques in health sciences: A methodological review.

BACKGROUND: Delphi techniques are conducted across different subfields in the health sciences. The reporting practices of studies using Delphi techniques vary, and current reporting guidelines for Delphi techniques focus on individual subfields of the health sciences or on different aspects of research and are therefore of limited applicability. The aim of this article was to identify similarities, differences, and possible shortcomings of existing Delphi reporting guidelines and to draft an initial proposal for a comprehensively applicable reporting guideline. METHODS: A systematic literature search for reporting guidelines on Delphi studies was performed in existing data resources based on databases in the health sciences (Scopus, MEDLINE, CINAHL, Epistemonikos) including publications from 2016 to 2021. In June 2021, we conducted an additional search in PubMed and included further studies by contacting experts of the scientific Delphi expert network (DeWiss). Title and abstract screening of articles was performed, followed by a full-text screening of the articles included. We qualitatively and quantitatively evaluated, compared and contrasted the reporting guidelines identified using content analysis and discussed the results among the members of the Delphi expert network. RESULTS: We retrieved ten health science articles with reporting guidelines for Delphi studies. In analyzing them, we identified nine main categories (Justification, Expert panel, Questionnaire, Survey design, Process regulation, Analyses, Results, Discussion, Methods reflection & Ethics). The current reporting guidelines vary significantly, with only the aspect of consensus appearing in all of them. Frequency distributions show that most of the subcategories are only addressed in individual articles (e.g., meeting of participants, proceeding with the survey method, transfer of the results, validation, prevention of bias) and that epistemological foundations of the Delphi technique are rarely mentioned or reflected on. We drafted an initial proposal for Delphi reporting guidelines for the health science sector. DISCUSSION: A well-justified position concerning epistemological foundations of Delphi studies is necessary to make the quality of the process assessable and, along with the reporting of the process, to classify and compare study results. This will increase the acceptance of both the method in the health science sector and the results in medical practice. A Delphi reporting guideline must, above all, take into account the diversity of variants, subfield-related objectives and application areas, and their modifications of the Delphi technique in order to be comprehensively applicable in the health sciences. CONCLUSION: The results of our methodological review do not provide a final reporting guideline. The newly developed proposal is intended to encourage discussion and agreement in further analyses.

Delphi Technique in Health Sciences: A Map.

Objectives: In health sciences, the Delphi technique is primarily used by researchers when the available knowledge is incomplete or subject to uncertainty and other methods that provide higher levels of evidence cannot be used. The aim is to collect expert-based judgments and often to use them to identify consensus. In this map, we provide an overview of the fields of application for Delphi techniques in health sciences in this map and discuss the processes used and the quality of the findings. We use systematic reviews of Delphi techniques for the map, summarize their findings and examine them from a methodological perspective. Methods: Twelve systematic reviews of Delphi techniques from different sectors of the health sciences were identified and systematically analyzed. Results: The 12 systematic reviews show, that Delphi studies are typically carried out in two to three rounds with a deliberately selected panel of experts. A large number of modifications to the Delphi technique have now been developed. Significant weaknesses exist in the quality of the reporting. Conclusion: Based on the results, there is a need for clarification with regard to the methodological approaches of Delphi techniques, also with respect to any modification. Criteria for evaluating the quality of their execution and reporting also appear to be necessary. However, it should be noted that we cannot make any statements about the quality of execution of the Delphi studies but rather our results are exclusively based on the reported findings of the systematic reviews.

Qualitative and Quantitative DNA- and RNA-Based Analysis of the Bacterial Stomach Microbiota in Humans, Mice, and Gerbils.

Clinical interventions in the stomach have been linked to fecal microbiota alterations, suggesting a function of the stomach in gastrointestinal (GI) homeostasis. We sought to determine the taxonomic bacterial biogeography of the upper GI tract, including different sites within the human stomach (cardia, corpus, and antrum), adjacent upstream (esophagus) and downstream (duodenum) locations, and luminal contents (aspirate), as well as whole-stomach samples from mice and gerbils. Qualitative and quantitative DNA- and RNA-based taxonomic microbiota analyses were combined to study the relationship of relative and absolute bacterial abundances and transcriptionally active bacterial microbiota components in the stomach of humans and mice. Stomach microbiota compositions resembled those of esophagus and duodenum. However, along the descending GI tract, the relative abundances of specific oropharyngeal commensals decreased (Streptococcus) or increased (Rothia mucilaginosa, Porphyromonas, and Lachnospiraceae). Furthermore, the compositional similarity (weighted UniFrac) between stomach aspirates and esophageal biopsy samples increased with gastric Streptococcus relative abundance. In both human aspirate and mouse stomach samples, Firmicutes were more abundant among transcriptionally active bacteria than Bacteroidetes. The relative abundance of Firmicutes in the stomach was negatively correlated and that of Bacteroidetes was positively correlated with absolute bacterial abundance, suggesting a disproportionate increase of Bacteroidetes over Firmicutes at higher bacterial densities. Human, mouse, and gerbil stomach samples showed similarities at higher taxonomic levels but differences at lower taxonomic levels. Our findings suggest selective enrichment and depletion of specific bacterial taxa in the stomach and Firmicutes being transcriptionally more active than Bacteroidetes that increase in relative abundance with total bacterial load. IMPORTANCE Clinical stomach interventions, such as acid inhibition or bypass surgery, have been linked to fecal microbiota alterations. We demonstrate that the stomach microbiota largely overlaps those of adjacent gastrointestinal locations and identify gradual decreases and increases in the relative abundances of specific bacteria within the stomach, suggesting selective enrichment and depletion. Moreover, similarities between stomach and esophagus samples are proportional to the concentrations of Streptococcus (Firmicutes) in the stomach. The relative abundance of Firmicutes in the stomach, compared to that of Bacteroidetes, is increased in RNA relative to DNA, indicating higher transcriptional activity. Moreover, increased absolute bacterial loads are associated with decreased relative abundance of Firmicutes and higher relative abundance of Bacteroidetes. Our findings characterize the stomach microbiota as influenced by Bacteroidetes influx against a background of transcriptionally more active Firmicutes. Human, mouse, and gerbil stomach microbiotas differ at lower taxonomic levels, which might affect the utility of these model organisms.