Problem Representation in Experts and Novices: Part 2. Underlying Processing Mechanisms

It has been well established that experts and novices focus on different aspects of problems, with novices focusing more on surface features rather than on deep principled features of a problem. What is less clear are the mechanisms that underlie these differences in construal of problem representation. The current study, which uses an `old/new' recognition procedure, examines expert and novice representation of arithmetic equations in which the deep relational properties (i.e., principles of commutativity and associativity) were well known to both groups. Results indicate that both novices and experts encode both surface and principled features in the same serial manner, with surface features preceding principled features for both. At the same time, only for novices and not for experts, surface features compete with deep features, thus requiring additional resources to inhibit this attentional competition

Problem Representation in Experts and Novices: Part 1. Differences in the Content Of Representation

Two experiments examined the content of novice and expert representations for both surface and deep structural elements of arithmetic equations. Experiment 1, which used a forcedchoice categorization task in which surface features of equations (e.g., digits) competed with deep structural principles of mathematics (associativity and commutativity), found that experts were more likely to focus on principles in their judgments than were novices, who focused more often on surface elements. Experiment 2, using a similar task, introduced trials in which only principled elements varied. Novices were able to focus on principled elements in this case, but failed to transfer these representations when surface features were reintroduced

The relative burden of haemophilia A and the impact of target joint development on health-related quality of life: results from the ADVATE Post-Authorization Safety Surveillance (PASS) study.

Studies with haemophilia A (HA) patients have shown burden in health-related quality of life (HRQOL) when compared with general population norms. In the current study, HA patients' SF-36v2 health survey scores were compared with general population norms and to patients with other chronic conditions. The impact of target joints (TJs) on HRQOL was also examined. The sample was a subset of HA patients enrolled in the Post-Authorization Safety Surveillance (PASS) programme: a prospective open-label study in which ADVATE [Antihaemophilic Factor (Recombinant), Plasma/Albumin-Free Method] was prescribed. A total of 205 patients who were ≥ 18 years old and had SF-36v2 baseline scores were selected for this study. To measure the burden of HA on HRQOL, manova analyses compared these SF-36v2 scores to age- and gender-matched general population US and EU norms and to patients from other chronic condition groups. manova and correlational analyses examined the relations among TJ, age and SF-36v2 scores. Comparisons with general population norms confirm that HA negatively impacts physical, but not mental, HRQOL. Comparison with other chronic conditions shows the physical burden of HA is greater than for chronic back pain but similar to diabetes and rheumatoid arthritis, while the mental burden of HA is less than for all three patient groups. The presence of TJs was negatively associated with physical HRQOL, although this association was much larger for older patients (45+ years) than for younger ones. Physical, but not mental, HRQOL is diminished in HA patients. Target joints are associated with lower physical HRQOL, although this effect is moderated by age