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PubMed1983

Male mouse (Mus musculus) ultrasonic vocalizations to female urine: why is heterosexual experience necessary?

Previous research was consistent with the hypothesis that urinary chemosignals from female mice (Mus musculus) serve as a conditioned stimulus (CS) for the elicitation of male ultrasonic courtship vocalizations while some other unknown aspect of the female serves as an unconditioned stimulus (US). According to this hypothesis adult heterosexual experience is necessary for males to pair the urinary CS with the US. Three experiments further examined this hypothesis. Experiment 1 demonstrated that the hypothesized US was not female behavior. Experience with anesthesized males and females was just as effective as experience with awake conspecifics. Experiments 2 and 3, however, question the primacy of the Classical Conditioning hypothesis. In both experiments sexually naive males were allowed contact with either normal females or female surrogates. The female surrogates were neonatally castrated males (Experiment 2) or hypophysectomized females (Experiment 3), both of which appeared to possess the hypothesized US but not the urinary CS on the basis of previous research. While exposure to normal females caused the highest level of vocalization to urine from normal females, exposure to the two classes of female surrogates also resulted in vocalizations to the urine of normal females. Thus under some circumstances, males do not require experience with a normal female to emit ultrasounds to urine from normal females. Factors in addition to Classical Conditioning must be operating to account fully for the role of adult heterosexual experience in causing female urine to come to elicit male courtship vocalization.

Animals↗
PubMed2003

Secondary intervention following endovascular repair of abdominal aortic aneurysm: a single centre experience.

AIMS: We aim from a review of our early and late experience of secondary intervention for technical failures, to examine and describe the impact of endovascular and open interventions. METHODS: 108 Abdominal Aortic Aneurysms (AAAs) repaired endoluminally between 1995-2001 were analysed. In our early experience, during 1995/96 home made pre-expanded polytetrafluoroethylene grafts fixed with Palmaz stents were used (n = 26). In our later experience, 1997/2001 Talent (n = 70) or Zenith endografts (n = 12) were used. All cases underwent spiral CT at 5 days and 6 monthly intervals post-op. Angiography was performed when further intervention was intended. All technical failures requiring intervention or not were studied. RESULTS: There were 28 (26%) technical failures identified of which 14 of 26 (54%) occurred in our early experience, and 14 of 86 (16%) occurred in our later experience (p < 0.05). Eleven in all required open conversion at the time of endovascular repair. Our study cohort were the remaining 17 cases requiring secondary intervention, seven were from our early experience and 10 from our later experience. There were 12 endoleaks, including two as a result of graft migration, two graft occlusions, two graft distortions and one graft infection. Overall 10 (66%) technical failures were treated by endoluminal repair and seven (34%) by open methods. However, in our later experience significantly more endoluminal techniques (80%) were used (p < 0.05). CONCLUSIONS: Technical failure rates were significantly higher in our earlier experience. Open repair, which was a feature of our early experience, has been avoided over the final 3 years. Instead, endoluminal techniques were used without further morbidity or mortality. Aneurysm rupture has not so far been experienced in this experience.

Adult↗
PubMed1998

Physician experience caring for dying patients and its relationship to patient outcomes.

BACKGROUND: The quality of end-of-life care has become important to care systems and the public. No research has assessed how physician factors affect patient and family experience. OBJECTIVE: The objective of this study was to examine whether physicians' experience with dying is associated with differences in their patients' experiences while dying. METHODS: This was a prospective cohort study. Data were obtained from five geographically diverse teaching hospitals. The survey population was composed of 765 attending physicians who had at least one patient enrolled in a study of those with a high risk of dying. The patients were 8203 hospitalized adults who were at least 80 years of age or had one of nine serious illnesses. The physician survey provided information about physician characteristics. Physician experience with death was stratified into five groups according to self-reported rate of dying patients in the physician's practice. Patient outcomes included pain, anxiety, depression, satisfaction with pain relief, presence and timing of do-not-resuscitate orders, concordance with their physicians about cardiopulmonary resuscitation, and hospital resource use. RESULTS: Oncologists and pulmonologists or critical care physicians had more frequent contact with death. Physician characteristics other than specialty were not associated with death experience. Compared with the physician group having no experience with death, the adjusted odds ratios for accord on resuscitation preferences were 1.38 (95% confidence interval [CI], 0.96 to 1.98), 1.47 (95% CI, 1.03 to 2.11), 1.58 (95% CI, 1.10 to 2.26), and 1.64 (95% CI, 1.09 to 2.46) for the other four physician groups with progressively increasing experience. Other outcomes for patients were not associated with increasing physician experience. CONCLUSION: Most physicians have little experience with dying, and physicians' experience with death has little effect on patient outcomes. The concentration of experience in a small segment of physicians offers opportunities for targeting improvements in the care of dying patients, including physician education.

Journal Article↗
PubMed2004

Reproducibility of SELDI-TOF protein patterns in serum: comparing datasets from different experiments.

MOTIVATION: There has been much interest in using patterns derived from surface-enhanced laser desorption and ionization (SELDI) protein mass spectra from serum to differentiate samples from patients both with and without disease. Such patterns have been used without identification of the underlying proteins responsible. However, there are questions as to the stability of this procedure over multiple experiments. RESULTS: We compared SELDI proteomic spectra from serum from three experiments by the same group on separating ovarian cancer from normal tissue. These spectra are available on the web at http://clinicalproteomics.steem.com. In general, the results were not reproducible across experiments. Baseline correction prevents reproduction of the results for two of the experiments. In one experiment, there is evidence of a major shift in protocol mid-experiment which could bias the results. In another, structure in the noise regions of the spectra allows us to distinguish normal from cancer, suggesting that the normals and cancers were processed differently. Sets of features found to discriminate well in one experiment do not generalize to other experiments. Finally, the mass calibration in all three experiments appears suspect. Taken together, these and other concerns suggest that much of the structure uncovered in these experiments could be due to artifacts of sample processing, not to the underlying biology of cancer. We provide some guidelines for design and analysis in experiments like these to ensure better reproducible, biologically meaningfully results. AVAILABILITY: The MATLAB and Perl code used in our analyses is available at http://bioinformatics.mdanderson.org

Algorithms↗
PubMed1979

Subjective referral of the timing for a conscious sensory experience: a functional role for the somatosensory specific projection system in man.

Subjective experience of a peripherally-induced sensation is found to appear without the substantial delay found for the experience of a cortically-induced sensation. To explain this finding, in relation to the putative delay of up to about 500 ms for achieving the "neuronal adequacy" required to elicit the peripherally-induced experience, a modified hypothesis is proposed: for a peripheral sensory input, (a) the primary evoked response of sensory cortex to the specific projection (lemniscal) input is associated with a process that can serve as a 'time-marker'; and (b), after delayed neuronal adequacy is achieved, there is a subjective referral of the sensory experience backwards in time so as to coincide with this initial 'time-marker'. A crucial prediction of the hypothesis was experimentally tested in human subjects using suitably implanted electrodes, and the results provide specific support for the proposal. In this, the test stimuli to medial lemniscus (LM) and to surface of somatosensory cortex (C) were arranged so that a minimum train duration of 200 ms or more was required to produce any conscious sensory experience in each case. Each such cerebral stimulus could be temporally coupled with a peripheral one (usually skin, S) that required relatively negligible stimulus duration to produce a sensation. The sensory experiences induced by LM stimuli were found to be subjectively timed as if there were no delay relative to those for S, that is, as if the subjective experience for LM was referred to the onset rather than to the end of the required stimulus duration of 200 ms or more. On the other hand, sensory experiences induced by the C stimuli, which did not excite specific projection afferents, appeared to be subjectively timed with a substantial delay relative to those for S, that is, as if the time of the subjective experience coincided roughly with the end of the minimum duration required by the C stimuli. The newly proposed functional role for the specific projection system in temporal referral would be additional to its known role in spatial referral and discrimination. A temporal discrepancy between corresponding mental and physical events, i.e., between the timing of a subjective sensory experience and the time at which the state of 'neuronal adequacy' for giving rise to this experience is achieved, would introduce a novel experimentally-based feature into the concept of psychophysiological parallelism in the mind-brain relationship.

Brain Mapping↗
PubMed2002

Differences in clinical experiences based on gender of third-year medical students in a required family medicine preceptorship.

PURPOSE: To investigate whether the gender of a student or preceptor affects the students' level of experience with clinical skills in a preceptorship. METHOD: A total of 451 third-year medical students completed a required family medicine preceptorship during three academic years (1997-2000) at one medical school. Students recorded their highest levels of experience with 57 clinical skills at the completion of the preceptorship using a five-point scale. Mean levels of experience were compared according to student and preceptor gender and by student-preceptor gender dyads. RESULTS: For the majority of clinical skills, levels of experience did not differ according to gender of the student or preceptor. However, women students received more experience with seven of 12 female-specific skills and men students received more experience with two of three male-specific skills. Women preceptors provided more experience with seven of 12 female-specific skills, as well as with depression and anxiety; men preceptors provided more experience with procedures. For the vast majority of gender-specific skills, the highest levels of student experience were received by pairs of students and preceptors of the same gender who were seeing patients of their same gender; the lowest levels of experience occurred in student-preceptor pairs of the same gender seeing patients of the opposite gender. There was no evidence for student-preceptor interactions. CONCLUSIONS: The gender of a student and that of the preceptor affect the level of experience the student receives with a number of gender-specific skills and procedures. Ways should be found to minimize these differences in training.

Adult↗
PubMed2005

Cognitive performance is highly sensitive to prior experience in mice with a learning and memory deficit: failure leads to more failure.

The impact of a previously successful or unsuccessful experience on the subsequent acquisition of a related task is not well understood. The nature of past experience may have even greater impact in individuals with learning deficits, as their cognitive processes can be easily disrupted. Mice with a targeted disruption of the alpha and delta isoforms of the cAMP-response element-binding protein (CREB) gene (CREB(alphadelta-)-deficient mice) have a genetic vulnerability to impaired learning and memory that is highly influenced by experimental conditions. Thus, we studied the impact of prior successful and unsuccessful experiences on the degree to which CREB(alphadelta-)-deficient mice exhibit impaired spatial learning and memory in the Morris water maze (MWM). In Experiment 1, we replicated the cognitive deficit of CREB(alphadelta-)-deficient mice when given two trials per day with a 1-min intertrial interval (MWM2), and labeled this experience as a "failure." We rescued the deficit using four trials per day with a 3- to 5-min intertrial interval (MWM4) and labeled this experience a "success." In Experiment 2, a new, naive set of wild-type (WT) and CREB(alphadelta-)-deficient mice were randomly assigned to one of two sequence protocols to assess the influence of a success or a failure on subsequent performance. In Group 1, mice were first exposed to the MWM4 condition, followed by the more difficult MWM2 task. As expected, CREB(alphadelta-)-deficient mice performed well in the MWM4; they also performed well during reversal testing (MWM4R) where the goal location is changed. With this initial successful learning experience, the CREB(alphadelta-)-deficient mice then performed as well as WT mice in the MWM2, the condition in which they are known to be impaired. In contrast, CREB(alphadelta-)-deficient mice in Group 2 had an unsuccessful experience when first exposed to the MWM2 condition, and then also showed impairment in the MWM4, the condition in which they would normally perform well. This deficit was amplified when CREB(alphadelta-)-deficient mice were then tested in the reversal test. Sex differences in learning among CREB(alphadelta-)-deficient mice were amplified upon exposure to an unsuccessful learning experience. These data indicate that, under conditions of cognitive impairment, past experience can-depending on its nature-significantly facilitate or hinder future performance.

Animals↗
PubMed2004

The intensive care experience: development of the ICE questionnaire.

BACKGROUND: Previous research has shown that patients' reported memories of intensive care are often of unpleasant events which are described as frightening and persecutory in nature. Currently, there is no standardized way of assessing perceptions of such an experience or relating it to long-term outcome. AIMS: This paper describes the development of an intensive care experience questionnaire which aims to (a) identify the domains of such an experience, (b) assess and quantify that experience, and (c) explore its impact on short- and long-term emotional outcome. METHODS: Data from two studies are reported. Participants were non-elective patients and > or =18 years of age with an ICU stay > or =24 hours. Study 1 (n = 34) generated and developed items. Study 2 (n = 109) allowed evaluation of the factor analytic structure and psychometrics of the questionnaire. RESULTS: From a set of 31 items, exploratory factor analysis identified four components of the intensive care experience: 'awareness of surroundings' (nine items), 'frightening experiences' (six items), 'recall of experience' (five items), and 'satisfaction with care' (four items). Cronbach's alpha statistics were acceptable for each component (0.71-0.93). Correlational analysis with the subscales of the Hospital Anxiety and Depression Scale and Impact of Event Scale demonstrated concurrent and univariate predictive validity. The intensive care experience was associated with adverse emotional outcome in both the short- and long-term. DISCUSSION: The intensive care experience questionnaire identified four dimensions of experience and performed satisfactorily in these developmental analyses. Further study of an independent intensive care unit data set is necessary to confirm these findings, including the four-component structure. Development of a standardized measure provides the opportunity to increase our understanding of the intensive care experience. The questionnaire may be useful to inform the development of effective interventions to improve subsequent outcomes for these patients.

Adaptation, Psychological↗
PubMed2001

A two-locus model for experience-conditioned direction of paw usage in the mouse is suggested by dominant and recessive constitutive paw usage behaviours.

Left-right direction of paw usage in the mouse depends on the genotype and the directional nature of the test. There are two phenotypic classes; in some strains, direction of paw usage is learned or conditioned by the direction of the initial test chamber and the experience of reaching and, in other strains, paw usage is a constitutive behaviour not affected by previous experience. We report the evidence for locus heterogeneity in the cause of constitutive versus experience-conditioned paw usage from a phenotypic analysis of F1 hybrid generations from the experience-conditioned C57BL/6J, C3H/HeHa, and SWV strains and the constitutive CDS/Lay and DBA/2J strains. The F1 hybrids between strains of different phenotypic classes provide evidence of locus heterogeneity. Constitutive paw usage in CDS/Lay is phenotypically dominant to experience-conditioned behaviour in both C57BL/6J and SWV. However, constitutive paw usage in DBA/2J is phenotypically recessive to experience-conditioned behaviour in C57BL/6J and dominant to experience-conditioned behaviour in SWV. Among the experience-conditioned strains, C57BL/6J is highly lateralized but SWV is only weakly lateralized. Our data suggest a model in which C57BL/6J may have a "strong" allele that identifies a functional difference between the constitutive paw usage of CDS/Lay and DBA/2J. DBA/2J may have a loss-of-function mutation at the same locus that is recessive to the strong C57BL/6J allele. SWV may have a "weak" allele and the (SWV x D2)F1 compound heterozygote may be below a threshold for detectability of experience-conditioned behaviour, making the constitutive behaviour of DBA/2J appear to be dominant to the experience-conditioned behaviour of SWV. CDS/Lay may have a dominant allele at a second locus that suppresses experience-conditioned behaviour in all F1 hybrids.

Animals↗
PubMed2006

Determination of the minimum number of microarray experiments for discovery of gene expression patterns.

BACKGROUND: One type of DNA microarray experiment is discovery of gene expression patterns for a cell line undergoing a biological process over a series of time points. Two important issues with such an experiment are the number of time points, and the interval between them. In the absence of biological knowledge regarding appropriate values, it is natural to question whether the behaviour of progressively generated data may by itself determine a threshold beyond which further microarray experiments do not contribute to pattern discovery. Additionally, such a threshold implies a minimum number of microarray experiments, which is important given the cost of these experiments. RESULTS: We have developed a method for determining the minimum number of microarray experiments (i.e. time points) for temporal gene expression, assuming that the span between time points is given and the hierarchical clustering technique is used for gene expression pattern discovery. The key idea is a similarity measure for two clusterings which is expressed as a function of the data for progressive time points. While the experiments are underway, this function is evaluated. When the function reaches its maximum, it indicates the set of experiments reach a saturated state. Therefore, further experiments do not contribute to the discrimination of patterns. CONCLUSION: The method has been verified with two previously published gene expression datasets. For both experiments, the number of time points determined with our method is less than in the published experiments. It is noted that the overall approach is applicable to other clustering techniques.

Algorithms↗
PubMed2005

PsychMate: providing psychology majors the tools to do real experiments and learn empirical methods.

PsychMate is a set of software tools for undergraduate psychology students to run, develop, and analyze computerized experiments. It includes 30 psychological experiments in the areas of perception, cognition, social psychology, human factors, and cognitive neuroscience. Students run experiments themselves and see basic results immediately. The automatic spreadsheet analysis forms allow them to aggregate data and create analyses, presentations, and Web pages with a single click. Students can use the Psychology Experiment Authoring Kit experiment editor to create their own experiments in minutes and run experiments with other students using Web-based experiment-management tools. The BrainTutor and BrainViewer applications teach brain anatomy and permit students to analyze fMRI brain imaging data from subjects who have performed the same memory experiments in which they participated. PsychMate has been used in 83 classes in which 1,533 students submitted 5,464 completed experiments with few (less than 1%) requests for help and a very positive rating of the research experience.

Brain↗
PubMedDate not supplied

Welcome to the experience economy.

First there was agriculture, then manufactured goods, and eventually services. Each change represented a step up in economic value--a way for producers to distinguish their products from increasingly undifferentiated competitive offerings. Now, as services are in their turn becoming commoditized, companies are looking for the next higher value in an economic offering. Leading-edge companies are finding that it lies in staging experiences. To reach this higher level of competition, companies will have to learn how to design, sell, and deliver experiences that customers will readily pay for. An experience occurs when a company uses services as the stage--and goods as props--for engaging individuals in a way that creates a memorable event. And while experiences have always been at the heart of the entertainment business, any company stages an experience when it engages customers in a personal, memorable way. The lessons of pioneering experience providers, including the Walt Disney Company, can help companies learn how to compete in the experience economy. The authors offer five design principles that drive the creation of memorable experiences. First, create a consistent theme, one that resonates throughout the entire experience. Second, layer the theme with positive cues--for example, easy-to-follow signs. Third, eliminate negative cues, those visual or aural messages that distract or contradict the theme. Fourth, offer memorabilia that commemorate the experience for the user. Finally, engage all five senses--through sights, sounds, and so on--to heighten the experience and thus make it more memorable.

Anniversaries and Special Events↗
PubMed2004

Effects of Clinical Field-Experience Setting on Athletic Training Students' Perceived Percentage of Time Spent on Active Learning.

OBJECTIVE: Our purpose was to examine undergraduate athletic training students' perceptions of how time is utilized during clinical field experiences while enrolled in Commission on Accreditation of Allied Health Education Program (CAAHEP)-accredited athletic training programs and to determine the effects of clinical field-experience length and setting, academic standing, sex, clinical assignment, and National Collegiate Athletic Association level on active learning. DESIGN AND SETTING: Using the Athletic Training-Clinical Education Time Framework (AT-CETF) and Utilizing Time and Active Learning Survey, subjects completed a 1-day, self-reported observation of how their clinical field-experience time was utilized. SUBJECTS: Program directors at 131 CAAHEP-accredited athletic training programs were sent survey packages. Seventy-two (41%) male subjects and 105 (59%) female subjects from 25 institutions completed the survey packages. Eight of the 10 National Athletic Trainers' Association districts were represented in the study. MEASUREMENTS: The AT-CETF is a behavioral time-profiling framework that measures athletic training students' perceptions of utilization of clinical field-experience time based on the performance domains associated with the 1999 National Athletic Trainers' Association Board of Certification Role Delineation Study and literature related to time and learning. RESULTS: Subjects spent 51% of their clinical field-experience time engaged in active learning, 9% in managerial activities, 17% in unengaged activities, and 23% in waiting activities. Multiple 2 x 2 x 3 analyses of variance (length of clinical field experience x academic standing x clinical field-experience setting) revealed a significant difference between the levels of clinical field-experience setting and the dependent variables of perceived percentage of active learning time and waiting time. A 2 x 3 analysis of variance (sex x clinical assignment) revealed a significant difference between the levels of clinical assignment and the dependent variable of perceived percentage of active learning time. CONCLUSIONS: The type of clinical field-experience setting and clinical assignment affects the amount of time spent in active learning. Therefore, profiling students' use of time may allow educators to identify clinical field-experience settings that maximize active learning time, expose students to their own unique learning situations, and offer students access to clinical field-experience settings aligned with their professional goals.

Journal Article↗
PubMed2005

[An attempt at reforming genetics experiment for undergraduate course].

The four comprehensive experiments were concreted from a series of verifying genetics experiments, which are relatively specific. They were divided into four pieces of experiment modules: Drosophila melanogaster's classical comprehensive genetics experiment, Bio-Cytogenetics comprehensive experiment, Molecular Genetics comprehensive experiment and Population genetics experiment. The first three are major courses and the last one is a selective course. All of these four require experiment modules. These experiments should be comprehensive, designable and innovative. The lab should open to students the whole day in order to improve students' interest and skill in experiment. The ability to design and innovate experiment could be developed through the training.

Animals↗
PubMed1999

Adverse childhood experiences and smoking during adolescence and adulthood.

CONTEXT: In recent years, smoking among adolescents has increased and the decline of adult smoking has slowed to nearly a halt; new insights into tobacco dependency are needed to correct this situation. Long-term use of nicotine has been linked with self-medicating efforts to cope with negative emotional, neurobiological, and social effects of adverse childhood experiences. OBJECTIVE: To assess the relationship between adverse childhood experiences and 5 smoking behaviors. DESIGN: The ACE Study, a retrospective cohort survey including smoking and exposure to 8 categories of adverse childhood experiences (emotional, physical, and sexual abuse; a battered mother; parental separation or divorce; and growing up with a substance-abusing, mentally ill, or incarcerated household member), conducted from August to November 1995 and January to March 1996. SETTING: A primary care clinic for adult members of a large health maintenance organization in San Diego, Calif. PARTICIPANTS: A total of 9215 adults (4958 women and 4257 men with mean [SD] ages of 55.3 [15.7] and 58.1 [14.5] years, respectively) who responded to a survey questionnaire, which was mailed to all patients 1 week after a clinic visit. MAIN OUTCOME MEASURES: Smoking initiation by age 14 years or after age 18 years, and status as ever, current, or heavy smoker. RESULTS: At least 1 of 8 categories of adverse childhood experiences was reported by 63% of respondents. After adjusting for age, sex, race, and education, each category showed an increased risk for each smoking behavior, and these risks were comparable for each category of adverse childhood experiences. Compared with those reporting no adverse childhood experiences, persons reporting 5 or more categories had substantially higher risks of early smoking initiation (odds ratio [OR], 5.4; 95% confidence interval [CI], 4.1-7.1), ever smoking (OR, 3.1; 95% CI, 2.6-3.8), current smoking (OR, 2.1; 95% CI, 1.6-2.7), and heavy smoking (OR, 2.8; 95% CI, 1.9-4.2). Each relationship between smoking behavior and the number of adverse childhood experiences was strong and graded (P<.001). For any given number of adverse childhood experiences, recent problems with depressed affect were more common among smokers than among nonsmokers. CONCLUSIONS: Smoking was strongly associated with adverse childhood experiences. Primary prevention of adverse childhood experiences and improved treatment of exposed children could reduce smoking among both adolescents and adults.

Adolescent↗
PubMed1995

The relationship between outcome of liver transplantation and experience in new centers.

For several medical interventions, increasing experience results in improved outcome. This finding may result from better patient selection or increased skill levels. This report examines whether there is a relationship between center experience and patient outcome for liver transplantation, and if so, whether the relationship is explained by patient or donor selection or level of experience required to obtain optimal results. The United Network for Organ Sharing Scientific Liver Transplant Registry includes all procedures performed in the United States since October 1987. The date of the first transplantation and the number of operations performed were used to define 42 new and 27 experienced centers. Within new centers, experience was quantified by the sequence number of each transplantation. Characteristics of 6,180 recipients and donors were compared between new and experienced centers using the chi 2 test for association. A linear trend test identified whether these characteristics varied with experience within new centers. The independent association between experience in new centers and perioperative mortality was examined using logistic regression. Patient and donor selection criteria differ between experienced and new centers and change within new centers as experience is gained. Adjusting for calendar year and various patient and donor characteristics, perioperative mortality rates decrease in new centers as experience is gained. After 20 transplantations are performed, perioperative mortality in new centers is not significantly different than that in experienced centers. Criteria for recipient and donor selection change as centers gain experience. Despite these differences and improvements that have occurred over time, increasing experience in centers performing liver transplantations is associated with reduced perioperative mortality.

Adolescent↗
PubMedDate not supplied

Aortic aneurysm volume calculation: effect of operator experience.

BACKGROUND: We have successfully applied sequential volumetric analysis of abdominal aortic aneurysms to exclude endoleak in patients who have an aortic endostent. This study compared the effect of variable operator experience on volumetric calculation accuracy. METHODS: Four operators with different experience levels calculated abdominal aneurysm volumes in 10 patients at two different times (>/= 1 week apart). The four reviewers were ranked as having a high level of experience (one full-time laboratory worker specializing in three dimensions with 3 years of experience), a moderate level of experience (one part-time laboratory worker specializing in three dimensions/computed tomographic technician with 1 year of part-time experience), and a low level of experience (two individuals taught volumetric measurements for the purposes of this study: a fellow in abdominal imaging and a computed tomographic technician). All volumes were calculated with a GE Advantage 4.0 workstation (General Electric, Waukesha, WI, USA). RESULTS: Mean aneurysm volume and volume difference between two measurements were calculated for four operators. The average (standard deviation) percent volume differences were 1.2% (0.2%) for the experienced reader, 3.2% (0.3%) for the moderately experienced reader, and 6.0% (1.0%) and 5.8% (1.1%) for the two readers with light experience. Differences between averages were statistically significant (p < 0.005). CONCLUSION: We have defined a percent margin of error for aortic aneurysm volume measurement and have shown a direct correlate to level of experience. Diagnosis of endoleak based on aneurysm volume enlargement on serial scans needs to account for the level of operator experience.

Aortic Aneurysm, Abdominal↗
PubMed2006

A cross-sectional survey of the symptom experience of kidney transplant recipients.

BACKGROUND: Previous studies have shown that being able to assess and improve kidney transplant recipients' experience of the common side effects of long-term post-operative immunosuppressive drug therapy can positively affect their treatment compliance, and thus, their quality of life. However, more needs to be learned about the factors affecting the symptom experience of kidney transplant patients in Taiwan. OBJECTIVE: The purpose of this study was to further our understanding of kidney transplant recipients' symptom experience in Taiwan in order to improve their symptom experience, drug and other therapies, and overall quality of life. METHODS: A cross-sectional study was conducted with purposive sampling of transplant recipients from a hospital in southern Taiwan. Data were collected from August 23, 2003 to June 30, 2004. One hundred subjects participated and self-reported using a structured questionnaire. The reliability (alpha) of social support and symptom experience was 0.96 and 0.78, respectively. RESULTS: The results indicated that there were significant differences in physical symptom experience by gender and herbal medicine use, and in psychosocial symptom experience by educational level and herbal medicine use. Women, on an average, had more severe physical symptoms than men. A higher level of social support and herbal medicine use was associated with less severe physical symptoms among men and women. These three factors explained 22.5% of the variance in physical symptom experience: gender (13.0%), value support (6.1%) and herbal medicine use (3.4%). The factor with the highest explanatory value for the variance in psychosocial symptom experience was herbal medicine (7.8%), its use being associated with slightly lower levels of psychosocial symptoms. CONCLUSIONS: A better understanding of kidney transplant patients' symptom experience can improve health professionals' symptom appraisal efforts, enabling them to provide better quality care, encourage greater patient compliance, and ultimately, improve the quality of life for kidney transplant recipients.

Cross-Sectional Studies↗