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Highlights • Same-different and tetrad data give different discriminal distances. • Bootstrap results can be used to visualize bivariate uncertainty. • Unadjusted comparison of d' estimates from these test methods is not advised. • Same-different and tetrad test methods may measure different psychological constructs. Abstract Analysis of data arising from the same-different test method can be submitted to Thurstonian-derived modelling with the goal of estimating the sensory distance between two products (thediscriminal distance δ) and the response bias for responding "same" (τ). Previously it has been proposed that it is possible to use τ estimates from same-different test data to represent the consumer-relevant effect size, and thus be used as a criterion for evaluating sensory equivalency, including with other sensory discrimination test methods, such as the tetrad test method. In this paper we explore that proposal. Additionally we investigate δ and τ as bivariate parameters that are estimated with joint uncertainty. In a central-location test, untrained assessors (n = 292) from a commercial consumer database evaluated samples of polyurethane foams by pressing on the samples by hand. All assessors completed six same-different and six tetrad tests using an experimental design to balance the order of test methods and sample presentation orders. The τ estimates obtained from the same-different test method were large compared to what is usually observed in evaluations of food and beverage products that are evaluated by mouth. Estimates of δ were also large, indicating that many foam contrasts were discriminated readily, leading to lower precision of measurement. Estimates of δ from the same-different test method were larger than estimates of δ from the tetrad test method. Bootstrap simulations visualized the bivariate uncertainty of the parameter estimates. This evidence discourages the use of the estimate of τ from same-different data to contextualize estimates of δ from the same data, and strongly discourages using τ from same-different test data to contextualize estimates for δ from the tetrad test data without adjustment for test method. Findings raise questions about whether or not Thurstonian-derived parameter estimates for the same-different and tetrad test methods lie onthe same psychological continuum. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if data capture device type had a significant influence on sensory descriptive analysis results. 12 trained assessors evaluated 4 snack bar products in triplicate on each of three devices (iPod, iPad, external monitor). Four-way univariate analysis of variance detected no significant product by device interaction in 19 of 20 attributes. Products were ranked in a similar manner with regards to attribute intensity on all devices. Both Principal Component Analysis and Generalized Procrustes Analysis multivariate configurations showed very similar arrangements for all products and devices. The input device is identified as a potential factor in the trend toward lower absolute scale values with increasing screen sizes. Practical Applications The computerized devices that are available for sensory data collection have changed over the years. Research facilities often compare historical data to newly obtained data sets; however, the question remains: can data be compared when different data collection devices were used? This study determined that descriptive analysis test results are comparable if data are collected on an iPod, an iPad and a laptop with a monitor display. [ABSTRACT FROM AUTHOR]

Diagnostic tools for paediatric chronic constipation have been limited, leading to over 90% of patients with treatment-resistant constipation being diagnosed with chronic idiopathic constipation, with no discernible organic cause. Work in our institution suggests that a number of children with intractable symptoms actually have slow colonic transit leading to slow transit constipation. This paper reviews recent data suggesting that a significant number of the children with chronic treatment-resistant constipation may have organic causes (slow colonic transit and outlet obstruction) and suggests new approaches to the management of children with chronic treatment-resistant constipation. [ABSTRACT FROM AUTHOR]

Gyrodactylus Nordmann, 1832 is a genus of monogenean flatworms that is well-studied in Europe and best known for the destructive pathogen of Atlantic salmon, Gyrodactylus salaris Malmberg, 1957. However, there is a paucity of information on species of Gyrodactylus occurring elsewhere despite that the genus is thought to be extremely speciose. Here we present the first major molecular phylogeny of Gyrodactylus using samples from host fishes in North America. Our aims were to characterize species and molecular diversity of North American Gyrodactylus to allow a determination of their evolutionary relationship with congenerics sampled from Europe. Specimens belonging to 25 species of Gyrodactylus and closely related species from Canada and the northern United States of America were identified using morphology and sequenced at 18S rDNA and ITS2 rDNA (totaling ca. 1430 bp). Significant molecular groups in North American Gyrodactylus were found to correspond to a major division in the genus based on the structure of the male copulatory organ. Results corroborate earlier findings suggesting that the genus Fundulotrema Kritsky and Thatcher, 1977, traditionally thought to be distinct from Gyrodactylus owing to the presence of a peduncular bar, falls within Gyrodactylus. The usefulness and application of the broadly conserved 18S primers as a standard tool for Gyrodactylus taxonomy is discussed and advocated. [ABSTRACT FROM AUTHOR]