Sets of probability distributions, independence, and convexity

This paper analyzes concepts of independence and assumptions of convexity in the theory of sets of probability distributions. The starting point is Kyburg and Pittarelli's discussion of "convex Bayesianism" (in particular their proposals concerning E-admissibility, independence, and convexity). The paper offers an organized review of the literature on independence for sets of probability distributions; new results on graphoid properties and on the justification of "strong independence" (using exchangeability) are presented. Finally, the connection between Kyburg and Pittarelli's results and recent developments on the axiomatization of non-binary preferences, and its impact on "complete" independence, are described.

Aids and tuberculosis: coinfection from the perspective of the quality of life of patients

Tuberculosis (TB) and HIV coinfection adversely affects the lives of individuals in both the biological and psychosocial aspects. Aiming to describe the quality of life of individuals with HIV/TB coinfection, this descriptive cross-sectional study was conducted in Ribeirao Preto-SP. Participants were HIV-seropositive individuals with and without TB, using the WHOQOL HIV BREF. 115 individuals who were HIV-positive participated: 57 were coinfected and 58 were not; most were male heterosexuals, predominantly aged 40-49 years. Of those coinfected, most had lower education and income. In assessing the quality of life the coinfected individuals showed lower results in all areas, with significant differences in the Physical, Psychological, Level of Independence and Social Relations areas. TB and HIV / AIDS are stigmatized diseases, and overlap of the two may have severe consequences on the physical and psychosocial health of the individual.

LEISURE AND MENTAL HEALTH IN PEOPLE WITH HYPERTENSION: CONVERGENCE IN HEALTH EDUCATION

People with hypertension constantly deal with issues related to mental health due to the psychosocial determinants of this illness, and leisure is an important control strategy. The objective of this study was to promote health education to a group of hypertensive patients, through research-action, based on critical-social pedagogy, and taking into consideration the participants' perception of leisure. Educational activities were conducted and, following, an evaluation was performed regarding the subjects' opinion about the impact of leisure on their lives and mental health. The group perceived leisure as a coping strategy for loneliness and also as a late development of independence; it was also regarded as a means of socialization and as a promotion of mental health. These perceptions revealed two themes: aging, leisure, and chronic disease; and knowledge and leisure experiences. Educational actions, such as group dynamics and discussions, were planned considering these themes with the purpose of providing the necessary conditions for socializing and exchanging experiences.

Second-trimester soft markers: relation to first-trimester nuchal translucency in unaffected pregnancies

Objective Genetic sonography following first-trimester combined screening appears to increase substantially detection rates for Down syndrome but it relies on the unproved assumption of independence between these tests. In this study we aimed to investigate the relationship between first-trimester nuchal translucency (NT) and a series of second-trimester soft markers and structural defects in unaffected pregnancies. Methods NT measurement in the first trimester was followed by second-trimester scan (18 to 23 + 6 weeks) including examination for three categorical markers (intracardiac echogenic foci, hyperechogenic bowel and structural defects) and measurement of nasal bone length, nuchal-fold thickness, femur length, humerus length, renal pelvis diameter and prenasal thickness. All continuous variables were expressed in multiples of the median (MoM) for gestation and correlation coefficients between log-transformed NT and second-trimester variables were calculated. In addition, frequencies of soft markers and structural defects in cases with increased NT were compared to those with normal NT, using MoM cut-offs. Results In a dataset of 1970 cases, NT was significantly correlated (P < 0.05) with all second-trimester continuous variables, the correlation being strongest for nuchal-fold thickness (r = 0.10). There was a higher frequency of cases with second-trimester nuchal-fold thickness above the 97.5th centile (10.7 vs. 2.2%) and hyperechogenic bowel (2.4 vs. 0.1%) in cases with increased NT. Conclusions Straightforward reassessment of risk using likelihood ratios derived from the second-trimester genetic sonogram might lead to inaccurate estimates. Multivariate models using continuous second-trimester variables might be preferable in sequential screening strategies. Copyright. 2012 ISUOG. Published by John Wiley & Sons, Ltd.

Medical adverse events in elderly hospitalized patients: A prospective study

OBJECTIVES: To determine the frequency of medical adverse events in elderly patients admitted to an acute care geriatric unit, the predictive factors of occurrence, and the correlation between adverse events and hospital mortality rates. METHODS: This prospective study included 171 admissions of patients aged 60 years and older in the acute care geriatric unit in a teaching hospital in Brazil between 2007 and 2008. The following variables were assessed at admission: the patient age, gender, number of prescription drugs, geriatric syndromes (e. g., immobility, postural instability, dementia, depression, delirium, and incontinence), comorbidities, functional status (evaluated with the Katz Index of Independence in Activities of Daily Living), and severity of illness (evaluated with the Simplified Acute Physiology Score II). The incidence of delirium, infection, mortality, and the prescription of potentially inappropriate medications (based on the Beers criteria) were assessed during hospitalization. An observer who was uninvolved in patient care reported the adverse events. RESULTS: The mean age of the sample was 78.12 years. A total of 187 medical adverse events occurred in 94 admissions (55%). The predictors of medical adverse events were undetermined. Compared with the patients with no adverse events, the patients with medical adverse events had a significantly longer hospital stay (21.41 +/- 15.08 days versus 10.91 +/- 7.21 days) and a higher mortality rate (39 deaths [41.5%] versus 17 deaths [22.1%]). Mortality was significantly predicted by the Simplified Acute Physiology Score II score (odds ratio [OR] = 1.13, confidence interval [CI] 95%, 1.07 to 1.20), the Katz score (OR = 1.47, CI 95%, 1.18 to 1.83), and medical adverse events (OR = 3.59, CI 95%, 1.55 to 8.30). CONCLUSION: Medical adverse events should be monitored in every elderly hospitalized patient because there is no risk profile for susceptible patients, and the consequences of adverse events are serious, sometimes leading to longer hospital stays or even death.

Abdominoperineal Excision: Evolution of a Centenary Operation

During the last century, great improvements have been made in rectal cancer management regarding preoperative staging, pathologic assessment, surgical technique, and multimodal therapies. Surgically, there was a move from a strategy characterized by simple perineal excision to complex procedures performed by means of a laparoscopic approach, and more recently with the aid of robotic systems. Perhaps the most important advance is that rectal cancer is no longer a fatal disease as it was at the beginning of the 20th century. This achievement is definitely due in part to Ernest Mile's contribution regarding lymphatic spread of tumor cells, which helped clarify the natural history of the disease and the proper treatment alternatives. He advocated a combined approach with the rationale to clear "the zone of upward spread." The aim of the present paper is to present a brief review concerning the evolution of rectal cancer surgery, focusing attention on Miles' abdominoperineal excision of the rectum (APR) and its controversies and refinements over time. Although APR has currently been restricted to a small proportion of patients with low rectal cancer, recent propositions to excise the rectum performing a wider perineal and a proper pelvic floor resection have renewed interest on this procedure, confirming that Ernest Miles' original ideas still influence rectal cancer management after more than 100 years.