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Normal Practice (normal + practice)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Decision-making models in the analysis of portal films: A clinical pilot study

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 1 2000
Andrew See
SUMMARY Portal films continue to play an important role in the verification of radiotherapy treatment. There is still some discussion, however, as to what action should be taken after a port film has shown a radiation field deviation from the prescribed volume. It was the aim of the present pilot study to investigate the performance of three decision-making models (,Amsterdam', ,Quebec' and ,Newcastle') and an expert panel basing their decision on intuition rather than formal rules after portal film acquisition in a clinical setting. Portal films were acquired on every day during the first week of treatment for five head and neck and five prostate cancer patients (diagnostic phase). If required, the field position was modified according to our normal practice following the recommendation of the expert panel. In order to analyse the results of the models, however, additional port films were taken in the following 3 treatment weeks with the patient moved as required by the different models (intervention phase). The portal films were taken over 4 consecutive days, positioning the patient according to each of the different models on one day each. None of the models diagnosed a field misplacement in the head and neck patients, while the ,Amsterdam' and ,Quebec' models predicted a move in one prostate patient. The ,Newcastle' model, which is based on Hotelling's T 2 statistic, proved to be more sensitive and diagnosed a systematic displacement for three prostate patients. The intervention phase confirmed the diagnosis of the model, even if the three portal films taken with the patient position adjusted as required by the model proved to be insufficient to demonstrate an improvement. The ,Newcastle' model does not rely on assumptions about the random movement of patients and requires five portal films before a decision can be reached. This approach lends itself well to incorporation into electronic portal imaging ,packages', where repeated image acquisitions present no logistical difficulty. [source]

The literacy curriculum and use of an Integrated Learning System

JOURNAL OF RESEARCH IN READING, Issue 2 2000
Larry Miller
This article describes one aspect of a year-long study of primary level teachers' and children's (Grades 1-3; children aged 6-9 years) use of the language arts component of SuccessMaker, an Integrated Learning System (ILS). Using information gathered from teacher surveys and classroom observation, we documented areas where the curricula embedded in the ILS were congruent with teachers' normal curricula and pedagogical practices. However, we also found numerous instances of incongruity. To illustrate our findings we use the case of phonics instruction to reveal discrepancies between normal practice and computer-based learning. The differences in content, presentation sequence and instructional practices raise issues about the appropriate relationship between computer-based instruction and teachers' normal practices. [source]

Routine testing for mismatch repair deficiency in sporadic colorectal cancer is justified

THE JOURNAL OF PATHOLOGY, Issue 4 2005
Robyn Lynne Ward
Abstract This study prospectively examines the accuracy of immunohistochemical staining in the identification of mismatch repair defective (MMRD) colorectal cancer in routine clinical practice. The potential impact of this information on decisions regarding adjuvant treatment and germline testing were quantified. A consecutive series of fresh tissue (836 cancers) was obtained from 786 individuals undergoing curative surgery for colorectal cancer at one institution. As part of normal practice, each tumour was screened for the expression of MLH1 and MSH2 by immunohistochemical staining (IHC) and relevant clinicopathological details were documented. Microsatellite instability (MSI) was assessed using standard markers. Overall, 108 (13%) tumours showed loss of staining for either MLH1 (92 tumours) or MSH2 (16 tumours). The positive predictive value of mismatch repair IHC when used alone in the detection of MSI tumours was 88%, and the negative predictive value was 97%. Specificity and positive predictive value were improved by correlation with microsatellite status. Tumour stage (HR 3.5, 95% CI 2.0,6.0), vascular space invasion (HR 1.9, 95% CI 1.2,3.0) and mismatch repair deficiency (HR 0.2, 95% CI 0.05,0.87) were independent prognostic factors in stages II and III disease. Screening by mismatch repair IHC could reasonably have been expected to prevent ineffective treatment in 3.6% of stage II and 7.6% of stage III patients. The frequency of germline mismatch repair mutations was 0.8%, representing six unsuspected hereditary non-polyposis colorectal cancer (HNPCC) cases. Routine screening of colorectal cancers by mismatch repair IHC identifies individuals at low risk of relapse, and can prevent unnecessary adjuvant treatments in a significant number of individuals. Abnormal immunohistochemistry should be confirmed by microsatellite testing to ensure that false-positive results do not adversely impact on treatment decisions. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]

Validation of the quality of The National Pain Database for pain management services in the United Kingdom

ANAESTHESIA, Issue 11 2008
G. C. Hall
Summary Data on specialist pain management is scarce. We evaluated PainDB, a database which aggregates this information from UK pain clinics. PainDB entries for 1120 patients (2648 consultations) were compared to records at 30 pain clinics. Staff were surveyed about normal practice at 28 sites. First consultations (17 135) on the aggregated PainDB were analysed for 2003 for omissions. Those consultations included on PainDB (54.6%) showed good concurrence with written notes (88.1%), with no pattern for the missing visits. Questionnaire responses were often absent from notes (56%) and diagnosis was most frequently omitted from PainDB (12.4,18.4%). Clinic staff overestimated completeness. Despite commitment, PainDB is currently unsuitable for research or audit. As routine hospital data should provide information on activity, specific questions on severity and outcome could be answered by short-term recording of predefined variables. [source]

Effects of density and food ration on the growth rate, mortality and biomass return of abalone in slab tanks

AQUACULTURE RESEARCH, Issue 13 2009
Matthew Wassnig
Abstract We determined how varying stocking density and food ration can influence the growth, mortality and biomass return of abalone raised in slab tanks. The abalone used were 2- year-old hybrids of Haliotis laevigata and Haliotis rubra. The experimental design involved replicate tanks and three levels of each factor (normal practice and ±20% density or food ration). Although increasing density from that typically used in farm practices reduced the growth rate by roughly 6%, biomass return increased by 15.5%, over the 9-month period. Increasing feed ration by 20% boosted biomass by significantly increasing abalone growth during the first 3 months by 4%, but was less effective as the animals grew. Growth, mortality and food conversion ratios were optimized in tanks with a low density and a low feed ration, but economic gains were dominated by the increased biomass return from tanks with a higher stocking density. It is thought that reduced dissolved oxygen and differing access to food contributed to the patterns observed. [source]