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At least 19 recordsLinked to original sources
PubMed1992

School-based theories of pupil assessment: a case study.

Case study design was used in this investigation of the pupil assessment theories of two middle school physical education teachers whose program was identified as a good program in which pupil assessment was taking place. An assumption guiding the study was that teachers' actions are rational and are designed to produce desired results. Therefore, a comparison is made only between two theories of action (espoused and enacted) rather than between theory and practice. Informal and semistructured interviews were employed to elicit teachers' espoused theories, and enacted theories were identified during field visits over a semester in which classes were observed and school documents examined. Teachers' theories of assessment are identified for the categories of participation, effort, and improvement; grading; written tests; fitness testing; performance tests; and formative recordkeeping. Espoused and enacted theories are then examined for congruency. The highest level of incongruency was found in the areas of performance tests and formative recordkeeping. Barriers to the use of pupil assessment techniques in this program include organizational, knowledge, and contextual factors. Change in the assessment practices of secondary teachers may be facilitated, however, through the identification and examination of teachers' theories of assessment by both preservice and inservice teachers.

Case-Control Studies↗
PubMed2025

Persistent gaps and errors in reference databases impede ecologically meaningful taxonomy assignments in 18S rRNA studies: a case study of terrestrial and marine nematodes.

In metabarcoding studies, Linnaean taxonomy assignments of Operational Taxonomic Units (OTUs) or Amplicon Sequence Variants (ASVs) underpin many downstream bioinformatics analyses and ecological interpretations of environmental DNA (eDNA) datasets. However, public molecular databases (i.e., SILVA, EUKARYOME, BOLD) for most microbial metazoan phyla (nematodes, tardigrades, kinorhynchs, etc.) are sparsely populated, negatively impacting our ability to assign ecologically meaningful taxonomy to these understudied groups. Additionally, the choice of bioinformatics parameters and computational algorithms can further impact the accuracy of eDNA taxonomy assignments. Here, we use two in-silico datasets to show that taxonomy assignments using the 18S rRNA gene can be dramatically improved by curating Linnaean taxonomy strings associated with each reference sequence and closing phylogenetic gaps by improving taxon sampling. Using free-living nematodes as a case study, we applied two commonly used taxonomy assignment algorithms (BLAST+ and the QIIME2 Naïve Bayes classifier) across six iterations of the SILVA 138 reference database to evaluate the precision and accuracy of taxonomy assignments. The BLAST+ top hit with a 90% sequence similarity cutoff often returned the highest percentage of correctly assigned taxonomy at the genus level, and the QIIME2 Naïve Bayes classifier performed similarly well when paired with a reference database containing corrected taxonomy strings. Our results highlight the urgent need for phylogenetically-informed expansions of public reference databases (encompassing both genomes and common gene markers), focused on poorly sampled lineages which are now robustly recovered via eDNA metabarcoding approaches. Additional taxonomy curation efforts should be applied to popular reference databases such as SILVA, and taxon sampling could be rapidly improved by more frequent incorporation of newly published GenBank sequences linked to genus and/or species level identifications.

18S rRNA metabarcoding↗
PubMed1988

Disease outbreak investigation. Three case studies.

Three case studies of the investigation of outbreaks of disease or deviations from target performance are presented. The first is a study of a mastitis problem in a dairy herd, made evident by increased somatic cell counts. The pattern of the production problem is carefully analyzed and conclusions are reached that indicate an infection with environmental contaminant organisms, thus permitting control measures to be introduced. The second case study is an investigation of an outbreak of neonatal mortality in sheep. Analysis suggests a multiple etiology, with infection by border disease virus predominating. The third case study describes the investigation of foothill abortion in a beef herd in California and demonstrates the use of epidemiologic techniques to try to identify the source of infection in a subgroup of the study population, thus allowing specific control measures to be introduced.

Abortion, Veterinary↗
PubMed1985

Dietary management of rumination: four case studies.

Four case studies are presented in which the amount of dietary intake directly affected the rate of post-meal ruminating in mentally retarded clients. In the first case small increases in meal size (8, 12, 16, and 24 oz) resulted in slight increases in rumination. When in the second and third cases, the dietary increases were larger (36, 42, and 50 oz) the results were rapid and significant decreases in rumination. In the final case study the subject was allowed to free feed to a satiation criteria that was continued for 196 days to determine the long-term effectiveness of treatment. The subject ceased ruminating until conditions were reversed. These studies are discussed in terms of treatment strategies and generality to other kinds of behavior.

Adolescent↗
PubMed1992

An evaluation of pre-registration midwifery education in England. Research design: a case study approach.

In this paper some aspects of research design are described and discussed. A national study to evaluate pre-registration midwifery education in England is currently in progress. As part of that study six case study sites have been selected. How those sites were selected and the theory and method of the case study approach are discussed in this paper. The value of the case study approach is discussed as are methodological issues of the case study method. What is a case? Are case studies representative? How can you generalise from case studies? What is theoretical sampling? What is the difference between statistical and logical inference? These are some of the questions raised and examined. It is suggested that an understanding of these theoretical issues and the research process is important to understand the research findings. By making the research design explicit and describing the research process the study also adopts a reflexive approach.

Education, Nursing↗
PubMed1987

Episodic reactive dysphonia: a case study.

This case study exemplifies successful diagnosis through stroboscopic fiberoptic examination, illustrates the critical importance of a careful case history, and demonstrates potential hazards of supposedly benign environmental substances for hypersensitive individuals.

Adult↗
PubMed1979

Rehabilitation of alexia: a case study.

This case study described the success of a technique labeled Multiple Oral Rereading (MOR) in the remediation of a case of acquired alexia in an adult male. Unusually slow visual-verbal processing characteristic of this patient is sometimes noted in dyslexic children. The possibility that MOR might prove effective for other selected cases of acquired alexia and "developmental" dyslexia is considered.

Adult↗