The Use of Health Service Areas for Measuring Provider Availability

Measurement of the availability of health care providers in a geographic area is a useful component in assessing access to health care. One of the problems associated with the county provider-to-population ratio as a measure of availability is that patients frequently travel outside their counties of residence for health care, especially those residing in non-metropolitan counties. Thus, in measuring the number of providers per capita, it is important that the geographic unit of analysis be a health service area. We have defined health care service areas for the coterminous United States, based on 1988 Medicare data on travel patterns between counties for routine hospital care. We used hierarchical cluster analysis to group counties into 802 service areas. More than one half of the service areas include only non-metropolitan counties. The service areas vary substantially in the availability of health care resources as measured by physicians and hospital beds per 100,000 population. For almost all of the service areas, the majority of hospital stays by area residents occur within the service area. In contrast, for 39 percent of counties, the majority of hospital stays by county residents occur outside the county. Thus, the service areas are a more appropriate georgraphic unit than the county for measuring the availability of health care

37 Gbps transmission over 200 m of MMF using single cycle subcarrier modulation and a VCSEL with 20 GHz modulation bandwidth

We report transmission at 37.2 Gb/s over 200 m of multimode fibre using a directly modulated VCSEL operating at 850 nm, using 20 GHz modulation bandwidth

Selective serotonin reuptake inhibitors during pregnancy and risk of persistent pulmonary hypertension in the newborn: population based cohort study from the five Nordic countries

Objective: To assess whether maternal use of selective serotonin reuptake inhibitors (SSRIs) increases the risk of persistent pulmonary hypertension in the newborn, and whether such an effect might differ between specific SSRIs. Design: Population based cohort study using data from the national health registers. Setting: Denmark, Finland, Iceland, Norway, and Sweden, 1996-2007. Participants: More than 1.6 million infants born after gestational week 33. Main outcome measures: Risks of persistent pulmonary hypertension of the newborn associated with early and late exposure to SSRIs during pregnancy and adjusted for important maternal and pregnancy characteristics. Comparisons were made between infants exposed and not exposed to SSRIs. Results: Around 30 000 women had used SSRIs during pregnancy and 11 014 had been dispensed an SSRI later than gestational week 20. Exposure to SSRIs in late pregnancy was associated with an increased risk of persistent pulmonary hypertension in the newborn: 33 of 11 014 exposed infants (absolute risk 3 per 1000 liveborn infants compared with the background incidence of 1.2 per 1000); adjusted odds ratio 2.1 (95% confidence interval 1.5 to 3.0). The increased risks of persistent pulmonary hypertension in the newborn for each of the specific SSRIs (sertraline, citalopram, paroxetine, and fluoxetine) were of similar magnitude. Filling a prescription with SSRIs before gestational week 8 yielded slightly increased risks: adjusted odds ratio 1.4 (95% confidence interval 1.0 to 2.0). Conclusions: The risk of persistent pulmonary hypertension of the newborn is low, but use of SSRIs in late pregnancy increases that risk more than twofold. The increased risk seems to be a class effect.publishedVersio

A cartographic study of hospital utilization in the county of Uppsala

In this study the question whether increased resources in community based primary care lead to decreased utilization of in-patient care has been analysed. Two alternative types of analysis were compared: a municipality-based analysis and a cartographic analysis based on non-administrative reference areas. The study material consisted of person-based data from Uppsala County in Sweden. The cartographic analyses revealed important characteristics of the utilization pattern, which would not have been possible to ascertain using traditional methods such as analyses based on administrative areas. Thus, the cartographic analysis gave some support to the hypothesis that increased resources to primary care will reduce the utilization of in-patient care.cartographic analyses person-based analyses health care utilization in-patient care primary care

Psychotropic drug use in a Swedish community-- The importance of demographic and socioeconomic factors

In this study the importance of demographic and socioeconomic factors for the use of psychotropic drugs in the general population of a Swedish community was studied using data from a research registry on prescriptions. The study showed that age, gender, marital status, socioeconomic status and distance to the health center had independent and significant effects on the use of psychotropic drugs. Age was of very great importance; the proportion of users was more than ten times greater among individuals aged 75-84 years than among those aged 18-34 years. Furthermore it was approximately twice as common with those drugs among women as compared to men. Differences with regard to marital and socioeconomic status were also present but these were generally small except in certain groups such as men aged 35-44 who were not employed, divorced men aged 45-54 and 55-64 years and single women aged 35-44 years.pharmacoepidemiology psychotropic drugs general population demographic factors socioeconomic factors

An Experimental Study of Liquid-Phase Heat Transfer in Multiport Minichannel Tubes

Heat transfer has been evaluated experimentally on the tube side of three different minichannel tubes, so-called multiport extruded (MPE) tubes, with different cross-section geometry. The objective was to find out which correlations, models, and relations should be used when predicting the performance of complete heat exchangers consisting of such tubes. The geometry of the tube channels or ducts was rectangular with different aspect ratios and one of the tubes was equipped with surface enlargements inside the channels. Evaluations were performed with four different secondary refrigerant liquids: water, propylene glycol, Hycool 20, and Temper-20. The laminar flow regime was the main focus of the investigations. Despite the shape of the minichannels, best agreement was found with a model presented by Gnielinski for laminar flow, developing temperature profile, and fully developed velocity profile in circular tubes with the constant wall temperature boundary condition

Liquid side heat transfer and pressure drop in finned-tube cooling-coils operated with secondary refrigerants

In this study full-scale experiments with two different conventional cooling-coils aimed for display cabinets were performed. Heat transfer and pressure drop on the liquid side for three different single phase secondary refrigerants were studied and compared to predictions by existing correlations. Predominantly, the laminar flow regime was studied. The results show that when predicting the heat transfer performance on the liquid side of a cooling-coil the Gnielinski correlation for thermally developing flow and uniform wall temperature boundary conditions (T) leads to good agreement for 0.0014<x*<0.017 if 50 < Re < 1700, assuming a new entrance length is formed after each U-bend. In addition, these entrance lengths must also be accounted for, when predicting the pressure drop on the liquid side of the cooling-coil. The uncertainty of measurement can be a problem in this type of investigations and this has been taken into consideration when analysing the results. (C) 2007 Elsevier Ltd and IIR. Ail rights reserved