Interval Preference

Tuned intervals were paired with each member of a series of mistuned intervals and the subjects were asked to indicate which interval they preferred. The tuned intervals were those with the simple arithmetic ratios of the natural scale. The series of mistuned intervals, both flat and sharp, extended approximately half way to the next simple-ratio interval. Pure tones from beat frequency oscillators were used and the exact interval was tuned by means of Lissajous\u27 figures on a cathode ray oscillograph. Mistuning, in terms of vibrations from the standard, was accomplished by the use of a variable pitch condenser

Uses of the case-control and cohort epidemiological approaches in pediatric practice and research

Increasing reliance is being placed on the use of quantitative epidemiological methods in the conduct and evaluation of pediatric research. The basic design features of two common types of observational studies, the case-control study and the cohort study, are reviewed. Advantages and disadvantages of these two study designs are discussed with emphasis on aspects such as the selection of comparison groups, avoiding selection and recall bias, gathering exposure information, controlling for potentially confounding factors, and methods of analysis. Appreciation of the salient features of these study design approaches should aid the clinician/researcher in the conduct of research endeavors as well as in critically reviewing the medical literature

Safety, cost-effectiveness and feasibility of daycase paracentesis in the management of malignant ascites with a focus on ovarian cancer

BACKGROUND: Paracentesis for malignant ascites is usually performed as an in-patient procedure, with a median length of stay (LoS) of 3–5 days, with intermittent clamping of the drain due to a perceived risk of hypotension. In this study, we assessed the safety of free drainage and the feasibility and cost-effectiveness of daycase paracentesis. METHOD: Ovarian cancer admissions at Hammersmith Hospital between July and October 2009 were audited (Stage 1). A total of 21 patients (Stage 2) subsequently underwent paracentesis with free drainage of ascites without intermittent clamping (October 2010–January 2011). Finally, 13 patients (19 paracenteses, Stage 3), were drained as a daycase (May–December 2011). RESULTS: Of 67 patients (Stage 1), 22% of admissions and 18% of bed-days were for paracentesis, with a median LoS of 4 days. In all, 81% of patients (Stage 2) drained completely without hypotension. Of four patients with hypotension, none was tachycardic or symptomatic. Daycase paracentesis achieved complete ascites drainage without complications, or the need for in-patient admission in 94.7% of cases (Stage 3), and cost £954 compared with £1473 for in-patient drainage. CONCLUSIONS: Free drainage of malignant ascites is safe. Daycase paracentesis is feasible, cost-effective and reduces hospital admissions, and potentially represents the standard of care for patients with malignant ascites