Areas Of High Rates Research Articles

Regional variations in multimorbidity burden among office-based physicians in Germany.

Multimorbidity is associated with higher utilization of healthcare services. However, many countries do not consider multimorbidity when estimating physician supply. The main aim of this study was to assess how regional multimorbidity levels can be integrated when estimating the need for office-based physician supply. Claims data were used to measure and compare the proportions of multimorbid patients of GPs, ophthalmologists, orthopaedic specialists and neurologists, and examine spatial variations through Bernoulli cluster analysis of regional multimorbidity levels. To explore the interrelationship between current capacities and spatial occurrence of high-rate clusters, clusters were compared with the current supply of physicians. About 17239488 individuals out of approximately 67 million records were classified as multimorbid. Multimorbidity levels varied greatly between physician disciplines (31.5-60.1%). Bernoulli cluster analysis demonstrated that many high-rate areas were found for all specialized physicians, but clusters varied partially by size and location. The comparison with current physician supply at cluster level showed that more than a third of clusters with a significantly higher share of morbid patients seeing a GP are met, on an average, by GP supply below targeted values. In turn, clusters with significantly higher multimorbidity levels of specialized physicians were met, on an average, by supply that exceeded targeted values. Our study offers an approach to how to include discipline-specific multimorbidity at area level when estimating physician supply and discusses its relevance. The outcomes of our article can be used by policymakers to advance current planning strategies and to improve the quality of office-based care.

Abstract C124: Identifying cancer disparities in the University of Chicago catchment area

Abstract (a) Cancer statistics are vital for helping doctors and researchers track cancer cases and use the data to find trends in various populations and patterns of occurrences, and make important public health decisions on where to direct funding, screening programs, and other steps to take in high-rate areas. This data can also tell doctors and researchers how effective some treatments are, based on the rise or fall in incidence and mortality rates, and can also help them pinpoint areas that need more attention. (b) Disparities in cancer incidence and mortality have not been described for the University of Chicago Comprehensive Cancer Center’s (UCCCC) patient catchment area (CA), the region from which the center draws its patients. This research aimed to describe incidence and mortality rates (2013-2017) for leading cancers in the CA, which consists of Cook County, IL; DuPage County, IL; Lake County, IL; Will County, IL; and Lake County, IN. Age-adjusted rates (per 100,000) were calculated for leading cancers by sex for each county, the CA, U.S., and IL. Racial disparities were also examined by comparing Black rates to White rates. (c) Incidence rates were higher in the CA compared to the U.S for all cancers data was available for: all sites combined, breast, and prostate. For males, mortality rates of prostate, colorectal, pancreatic, and stomach cancers were higher in the CA compared to the U.S. For females, mortality rates of breast, colorectal, myeloma, uterine, stomach, and bladder cancers, as well as all sites combined were higher in the CA compared to the U.S. By county, males experienced incidence rates of 8% to nearly 2.5 times higher and mortality rates 3% to over 1.5 times higher compared to the U.S. for various cancers. By county, females experienced incidence rates 5% to over 4 times higher and mortality rates 4% to over 1.5 times higher compared to the U.S. for various cancers. Lake County, IN generally had the highest incidence and mortality rates. Racial disparities in incidence and mortality were present for most cancers in the CA overall and by county. For males, racial disparities in mortality for prostate, stomach, and larynx are of greatest concern. For females, racial disparities in mortality for myeloma, cervical, and uterine are of greatest concern. (d) This research highlights important health inequities and priorities for the UCCC to reduce these disparities in the areas of cancer risk, prevention, and treatment. Citation Format: Joel Ssepuuya, Stephanie Zhang, Kelsey Meador, Lizeth Tamayo, Brandon Pierce. Identifying cancer disparities in the University of Chicago catchment area [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C124.

Geospatial analysis of cesarean section in Iran (2016–2020): exploring clustered patterns and measuring spatial interactions of available health services

BackgroundThe lives of babies and mothers are at risk due to the uneven distribution of healthcare facilities required for emergency cesarean sections (CS). However, CS without medical indications might cause complications for mothers and babies, which is a global health problem. Identifying spatiotemporal variations of CS rates in each geographical area could provide helpful information to understand the status of using CS services.MethodsThis cross-sectional study explored spatiotemporal patterns of CS in northeast Iran from 2016 to 2020. Space–time scan statistics and spatial interaction analysis were conducted using geographical information systems to visualize and explore patterns of CS services.ResultsThe temporal analysis identified 2017 and 2018 as the statistically significant high clustered times in terms of CS rate. Five purely spatial clusters were identified that were distributed heterogeneously in the study region and included 14 counties. The spatiotemporal analysis identified four clusters that included 13 counties as high-rate areas in different periods. According to spatial interaction analysis, there was a solid spatial concentration of hospital facilities in the political center of the study area. Moreover, a high degree of inequity was observed in spatial accessibility to CS hospitals in the study area.ConclusionsCS Spatiotemporal clusters in the study area reveal that CS use in different counties among women of childbearing age is significantly different in terms of location and time. This difference might be studied in future research to identify any overutilization of CS or lack of appropriate CS in clustered counties, as both put women at risk. Hospital capacity and distance from population centers to hospitals might play an essential role in CS rate variations and spatial interactions among people and CS facilities. As a result, some healthcare strategies, e.g., building new hospitals and empowering the existing local hospitals to perform CS in areas out of service, might be developed to decline spatial inequity.

Land Subsidence Measurement in Reclaimed Coastal Land: Noksan Using C-Band Sentinel-1 Radar Interferometry

Nur, A.-S.; Achmad, A.-R., and Lee, C.-W., 2020. Land subsidence measurement in reclaimed coastal land: Noksan using C-Band Sentinel-1 radar interferometry. In: Jung, H.-S.; Lee, S.; Ryu, J.-H., and Cui, T. (eds.), Advances in Geospatial Research of Coastal Environments. Journal of Coastal Research, Special Issue No. 102, pp. 218-223. Coconut Creek (Florida), ISSN 0749-0208.It has been 27 years since the beginning of the Noksan national industrial complex construction at downstream of the Nakdong River in Busan. The complex was built by landfilling a coastal area over one of Korea's deepest soft ground areas. Land subsidence occurred since the start of construction due to primary consolidation and secondary consolidation after the creation finished. Since secondary consolidation directly affects the structure over Noksan, it is crucial to monitor the subsidence rate. This study found that land subsidence happened in four areas of Noksan National Industrial Complex from 2017 to 2020 by applying Stamford Methods for Persistent Scatterer (StaMPS) time-series method using C-band Sentinel-1 SAR datasets from descending and ascending track. The results show land subsidence with a maximum velocity of 20.98 mm/year from descending track datasets and 20.92 mm/year from ascending track datasets. The highest rate area of land subsidence occurred in the south part of Noksan. Mean vertical deformation maps between descending and ascending track have been compared and show a good relationship with 0.93 of coefficient correlation. These approach methods in this study that using StaMPS could be used to monitor slow rate of land subsidence in reclaimed coastal land.

Mapping Geographical Patterns and High Rate Areas for Sexually Transmitted Infections in Portugal: A Retrospective Study Based on the National Epidemiological Surveillance System.

Monitoring disease variation using finer scales to identify high-rate communities is a critical aspect for precision public health and for efficient resource allocation. This study aimed to map the spatial patterns of chlamydia, gonorrhea, and syphilis; identify high-rate areas across Portuguese municipalities; and determine the association of these sexually transmitted infections (STIs) with socioeconomic deprivation, urbanicity level, and population density. The STI notifications at municipality level for the period 2015 to 2017 were obtained from Portugal's Epidemiologic Surveillance System (Sistema Nacional de Vigilância Epidemiológica). Spatial Bayesian models were used to calculate smoothed standardized notification rates, identify high- and low-rate areas and estimate associations (relative risk [RR], 95% credible intervals [95%CrI]). There were 4819 cases of chlamydia, gonorrhea, and syphilis reported, accounting for 15.3%, 33.2%, and 51.5% of the notifications, respectively. The STI notification rates were substantially higher in Porto and Lisbon Metropolitan Areas and concentrically disperse around those. Notification rates of the 3 STIs were strongly correlated (r > 0.8). Rates of gonorrhea (Q1-lowest density vs. Q5-highest RR, 2.10; 95% CrI, 1.08-4.25) and syphilis (RR, 3.16; 95% CrI, 2.00-5.13) were associated with population density. Notifications of chlamydia (Q1-least urban vs. Q5-most RR, 9.64; 95% CrI, 1.73-93.59) and syphilis (RR, 1.92; 95% CrI, 1.30-2.88) increased with urbanicity level. We also found that notification rates of gonorrhea were associated with socioeconomic deprivation (Q1-least vs. Q5-most deprived RR, 1.75; 95% CrI, 1.07-2.88). Wide spatial inequalities in STI notification rates were observed, which were predominantly concentrated in the 2 metropolitan areas of the country. Our findings can help guide more targeted interventions to reduce STIs incidence.

EPHX1 Tyr113His polymorphism contributes to hepatocellular carcinoma risk: evidfnce from a meta-analysis

To clarify the association between microsomal epoxide hydrolase gene (EPHX1) Tyr113His polymorphism and hepatocellular carcinoma (HCC) risk, a meta-analysis was performed. Overall, EPHX1 Tyr113His polymorphism was associated with increased risk of HCC. Subgroup analyses by status of Hardy-Weinberg equilibrium (HWE) in controls further confirmed this association. Through a literature search, 119 relevant records were identified, and 17 individual case-control studies from 13 publications were finally included, involving a total of 1,480 HCC cases and 2,564 controls. In subgroup analyses, increased associations were found in Asians, Caucasians, hepatitis B virus (HBV)- dominant areas, hepatitis C virus (HCV)-dominant areas, high-rate areas of HCC, and medium-rate areas of HCC, but not in Africans and low-rate areas of HCC, respectively. This meta-analysis suggests that EPHX1 Tyr113His polymorphism contributes to HCC risk.

Incidence, Mortality and Time Trends of Childhood Soft Tissue Sarcomas in Russia

ABSTRACT Aim: To estimate patterns and trends of childhood soft tissue sarcomas (STS) in Russia with respect to incidence and mortality data. Methods: The analysis was based on annual reports of Ministry of Health and Federal State Statistics Service on cases, deaths and person-years by gender, age, calendar year and region. Age-specific and age-adjusted rates were calculated. Additionally, the average annual percent change (AAPC) with 95% confidence interval (95% CI), derived from a Poisson regression model, was estimated. Excess or deficit of incidence rates for geographical areas were expressed as standardized incidence ratio (SIR; standardized to rate of Russia as whole). Results: STS represent 5.8% of all childhood malignancies in Russia registered during for 2008-2012, behind leukaemias, brain tumors, lymphomas and renal tumors. The age-adjusted incidence rate (ASR, world standards) of STS per 1,000,000 patients below the age of 15 years was 7.2 (774 incident cases). The highest age-specific incidence was observed in children aged 0-4 years (11.5 per 1,000,000). A significant incidence trend was shown with AAPC of 3.7% [95% CI 3.2-4.2] between 1989 and 2012. The largest increase was observed in children aged 0-4 years (AAPC=5.6% [95% CI 4.7- 6.5]. There were doubling of average Russian incidence rates in some areas such as Samarskaya oblast (about 15 cases per 1,000,000, SIR=2 [95% CI 1.3-2.8]. STS accounts for 10.8% of deaths from cancer in children in Russia and thus ranks third behind leukaemia and brain tumors. The age-adjusted mortality rate of STS per 1,000,000 patients below the age of 15 years for 2008-2012 was 4.3 (459 deaths). The highest age-specific incidence was observed in children aged 1-4 years (6.7 per 1,000,000). A significant increase of mortality between 1999 and 2012 was shown with AAPC of 3.2% [95% CI 1.8- 4.7]). The geographical differences of death rates were not analysed because of small numbers. Conclusions: Significant increase of both incidence and mortality for childhood STS were found in Russia for recent decades. Further study is required to explain higher rate areas. Disclosure: All authors have declared no conflicts of interest.

Risk factors associated with parents claiming personal-belief exemptions to school immunization requirements: Community and other influences on more skeptical parents in Oregon, 2006

With vaccine-preventable diseases at record lows, few studies investigate rising parent-claimed exemptions to school immunization requirements. After finding exemption clusters in Oregon, we hypothesized that exemption risk factors may vary among communities. We surveyed parents to identify risk factors for exemptions and evaluated risk factor differences among communities with differing exemption rates. Retrospective cohort study, multi-staged, population-proportionate sampling. Parents of 2004-05 Oregon elementary school children (N=2900). Parent-reported exemption status. The response rate was 55%. Compared to vaccinators, exemptors were significantly more likely to have: strong vaccine concerns (weighted adjusted odds ratio (aOR)=15.3, 95% CI 6.4-36.7); "vaccine-hesitant" concerns (aOR=2.3; 95% CI 1.0-5.0); >1 childbirth(s) at a non-hospital, alternative setting (aOR=3.6; 95% CI 1.6-8.0); distrust of local doctors (aOR=2.7; 95% CI 1.0-7.5); reported chiropractic healthcare for their youngest school-age child (aOR=3.9; 95% CI 1.8-8.5); and reported knowledge of someone with a vaccine-hurt child (aOR=1.8; 95% CI 0.9-3.4). Exemptors were less likely to have "pro-vaccine" beliefs (aOR=0.2; 95% CI 0.0-0.6) and less likely to report relying on print materials (aOR=0.4; 95% CI 0.2-0.8). The strengths of association differed significantly for those with strong vaccine concerns and those reporting knowledge of someone with a vaccine-hurt child, depending on residence in exemption-rate areas, e.g., exemptors in medium-rate areas were more likely to have strong vaccine concerns (aOR=13.5; 95% CI 5.4-34.0) than those in high-rate areas (aOR=9.7; 95% CI 3.7-25.4). Vaccine beliefs were important risk factors. That differing community-level exemption use modified the effects of several individual-level factors suggests that communities also influence parent decisions. Therefore, understanding community contexts and norms may be important when designing interventions.

Null genotypes of GSTM1 and GSTT1 contribute to hepatocellular carcinoma risk: Evidence from an updated meta-analysis

Studies investigating the associations between glutathione S-transferase (GST) genetic polymorphisms and hepatocellular carcinoma (HCC) risk have reported controversial results. Thus, a meta-analysis was performed to clarify the effects of GSTM1 and GSTT1 polymorphisms on HCC risk. We identified 132 relevant records through a literature search up to November 22, 2009, and 24 individual case-control studies from 23 publications were finally included, involving a total of 3349 HCC cases and 5609 controls. Subgroup analyses were performed by ethnicity, or by area according to the incidence rate and hepatitis virus status. Analyses of total relevant studies showed an increased HCC risk was significantly associated with null genotypes of GSTM1 (OR=1.26, 95% CI 1.03-1.54, p(OR)=0.027) and GSTT1 (OR=1.28, 95% CI 1.09-1.51, p(OR)=0.002). In addition, the GSTM1-GSTT1 interaction analysis showed that the dual null genotype of GSTM1/GSTT1 was significantly associated with increased HCC risk (OR=1.89, 95% CI 1.38-2.60, p(OR)<0.001). Subgroup analyses showed that the associations above were still statistically significant in Asians (p(GSTM1)=0.017, p(GSTT1)=0.001, p(Dual null genotype)<0.001), high-rate areas (p(GSTM1)=0.012, p(GSTT1)=0.006, p(Dual null genotype)<0.001), and HBV-dominant areas (p(GSTM1)=0.003, p(GSTT 1)=0.003, p(Dual null genotype)<0.001). This meta-analysis suggests null genotypes of GSTM1 and GSTT1 are both associated with increased HCC risk in Asians, and individuals with the dual null genotype of GSTM1/GSTT1 are particularly susceptible to developing HCC.

Meshing wireless personal area networks: Introducing IEEE 802.15.5

This article presents an overview of the IEEE project 802.15.5 that targets providing mesh capabilities to both high-rate and low-rate wireless personal area networks. Low-rate mesh is built on IEEE 802.15.4 MAC, while high-rate mesh utilizes IEEE 802.15.3 MAC. We seek to share our insights and motivations of the approach adopted in the major components of the standard instead of presenting a la carte items drawn in the specification. We hope this article helps readers of the 802.15.5 standard to better understand the rationale and intent of the protocol design.

Distributed Multiple Access Control for the Wireless Mesh Personal Area Networks

Mesh networking technologies for both high-rate and low-rate wireless personal area networks (WPANs) are under development by several standardization bodies. They are considering to adopt distributed TDMA MAC protocols to provide seamless user mobility as well as a good peer-to-peer QoS in WPAN mesh. It has been, however, pointed out that the absence of a central controller in the wireless TDMA MAC may cause a severe performance degradation: e.g., fair allocation, service differentiation, and admission control may be hard to achieve or can not be provided. In this paper, we suggest a new framework of resource allocation for the distributed MAC protocols in WPANs. Simulation results show that our algorithm achieves both a fair resource allocation and flexible service differentiations in a fully distributed way for mesh WPANs where the devices have high mobility and various requirements. We also provide an analytical modeling to discuss about its unique equilibrium and to compute the lengths of reserved time slots at the stable point.

High incidence of vascular reconstructions in socioeconomically deprived areas of an urban Swedish population

In Malmö approximately 250,000 citizens live in 17 administrative areas with substantial socioeconomic differences. At the single centre for arterial reconstruction, Malmö University Hospital, all procedures are registered prospectively. Between 1987 and 2002, 1832 Malmö citizens underwent reconstruction for peripheral arterial disease, either intermittent claudication (IC) or critical leg ischaemia (CLI). A socioeconomic score based on migration rate, percentage of residents with foreign citizenship/residents with foreign background, social welfare support dependency and unemployment rate has previously been developed and validated for each area. The relationship between socioeconomic score and area-specific standardized morbidity ratios (SMRs) after vascular reconstruction was analysed by population-weighted linear regression. The mean incidence of vascular reconstruction was 76 (range 27-106) per 100,000 person years. Age- and sex-adjusted SMRs ranged from 0.57 to 1.39. A strong correlation between SMR and socioeconomic score was found overall (R=0.63; P=0.007), in men (R=0.63; P=0.007) and in women (R=0.58; P=0.039), and for IC (R=0.58; P=0.015) and CLI (R=0.58; P=0.015). In an urban population with similar access to medical care, vascular reconstruction rates varied substantially. High-rate areas were characterized by inferior socioeconomic circumstances and a higher prevalence of smoking, hypertension and obesity.

Does more "appropriateness" explain higher rates of cardiac procedures among patients hospitalized with coronary heart disease?

There have been few studies of the extent to which differences in the pool of patients being managed might account for geographic variations in treatment rates. For two cardiac procedures, cardiac catheterization and revascularization, we evaluate the hypothesis that differences in "the percentage of patients for whom the procedure is appropriate" is a factor explaining variations in use rates among those hospitalized with coronary heart disease (CHD). Based on hospital utilization patterns in Massachusetts in 1990, we created 70 small geographic areas. Using 1992 Massachusetts Peer Review Organization data, areas were ranked from highest to lowest based on (empirical-Bayes-adjusted) hospitalization rates for each procedure. One thousand seven hundred four cases from 43 hospitals were sampled, roughly half each from high and low use areas. Half had a procedure and half were candidates for the same procedure but did not have it. For each procedure, medical records were reviewed to determine whether the procedure was (or, for those not having it, would have been) appropriate, based on criteria developed using a modified Delphi approach. Among those having either procedure, appropriateness rates were similar in high and low rate areas (P = 0.59 for catheterization and P = 0.30 for revascularization). However, among candidates for either procedure who did not have it, appropriateness for performing the procedure was greater in high-rate areas (41.4% vs. 32.1%, P = 0.05 for catheterization; 71.2% vs. 57.2%, P = 0.003, for revascularization). Among those hospitalized with CHD, appropriateness rates for two cardiac procedures are higher in areas with higher use rates.

Exploratory spatial analysis of pilot fatality rates in general aviation crashes using geographic information systems.

Geographic information systems and exploratory spatial analysis were used to describe the geographic characteristics of pilot fatality rates in 1983-1998 general aviation crashes within the continental United States. The authors plotted crash sites on a digital map; rates were computed at regular grid intersections and then interpolated by using geographic information systems. A test for significance was performed by using Monte Carlo simulations. Further analysis compared low-, medium-, and high-rate areas in relation to pilot characteristics, aircraft type, and crash circumstance. Of the 14,051 general aviation crashes studied, 31% were fatal. Seventy-four geographic areas were categorized as having low fatality rates and 53 as having high fatality rates. High-fatality-rate areas tended to be mountainous, such as the Rocky Mountains and the Appalachian region, whereas low-rate areas were relatively flat, such as the Great Plains. Further analysis comparing low-, medium-, and high-fatality-rate areas revealed that crashes in high-fatality-rate areas were more likely than crashes in other areas to have occurred under instrument meteorologic conditions and to involve aircraft fire. This study demonstrates that geographic information systems are a valuable tool for injury prevention and aviation safety research.

Paludismo importado: una enfermedad emergente

We aimed at knowing the epidemiological and clinical characteristics of imported malaria in Maresme county (Barcelona), Spain. A descriptive and retrospective study of patients diagnosed with imported malaria at the Hospital de Mataró (HM) (1982-2000). 64 cases of malaria were diagnosed, which supposed a significant increase in its incidence over the last decade. The disease mostly affected men (83%) as well as young and sub-Saharan immigrants (72%). 17% of affected people were immigrants' children. 50% cases were diagnosed in August-September. 80% of species corresponded to Plasmodium falciparum, either alone or in association with other species. Only 10% of patients underwent a correct chemoprophylaxis. Imported malaria is an emergent, potentially mortal, illness, which has to be taken into account in high-rate immigration areas. Prophylaxis compliance and knowledge is low.

Geographic distribution of stroke incidence within an urban population: relations to socioeconomic circumstances and prevalence of cardiovascular risk factors.

Geographic differences in stroke incidence indicate a potential for prevention. The present study from the city of Malmö, Sweden, sought to investigate whether incidence of stroke in residential areas is related to prevalence of cardiovascular risk factors and socioeconomic circumstances. The Stroke Register in Malmö, Sweden, was used for retrieval of the 3540 patients who suffered a first stroke between 1989 and 1998. The Malmö Diet and Cancer cohort (n=28 466) was used to assess area specific prevalence of hypertension, diabetes, smoking, and being overweight and for computation of a cardiovascular risk score. Socioeconomic circumstances for the 17 administrative areas were expressed in terms of a composite score. Standardized stroke incidence ranged among areas from 437 to 743 per 100 000 for men and from 223 to 518 per 100 000 for women. Socioeconomic score correlated significantly with area-specific stroke rates among men (r=-0.62, P=0.008) and women (r=-0.67, P=0.004). Incidence of stroke was significantly associated with cardiovascular risk score for each area (men, r=0.53, P<0.05; women, r=0.76, P<0.001). The cardiovascular score and the socioeconomic score together accounted for 44% of the geographic variance among men and 63% among women. Marked differences occurred in stroke incidence among residential areas within this urban population. High-rate areas were characterized by a higher prevalence of smoking, hypertension, diabetes, and being overweight and by inferior socioeconomic circumstances. These risk factors accounted for a substantial proportion of the geographic variance in incidence of stroke.

Determining the need for hip and knee arthroplasty: the role of clinical severity and patients' preferences.

Area variation in the use of surgical interventions such as arthroplasty is viewed as concerning and inappropriate. To determine whether area arthroplasty rates reflect patient-related demand factors, we estimated the need for and the willingness to undergo arthroplasty in a high- and a low-use area of Ontario, Canada. Population-based mail and telephone survey. All adults aged > or =55 years in a high (n = 21,925) and low (n = 26,293) arthroplasty use area. We determined arthritis severity and comorbidity with questionnaires, established the presence of arthritis with examination and radiographs, and evaluated willingness to have arthroplasty with interviews. Potential arthroplasty need was defined as severe arthritis, no absolute contraindication for surgery, and evidence of arthritis on examination and radiographs. Estimates of need were then adjusted for patients' willingness to undergo arthroplasty. Response rates were 72.0% for questionnaires and interviews. The potential need for arthroplasty was 36.3/1,000 respondents in the high-rate area compared with 28.5/1,000 in the low-rate area (P <0.0001). Among individuals with potential need, only 14.9% in the high-rate area and 8.5% in the low-rate area were definitely willing to undergo arthroplasty (P = 0.03), yielding adjusted estimates of need of 5.4/1,000 and 2.4/1,000 in the high- and low-rate areas, respectively. Demonstrable need and willingness were greater in the high-rate area, suggesting these factors explain in part the observed geographic rate variations for this procedure. Among those with severe arthritis, no more than 15% were definitely willing to undergo arthroplasty, emphasizing the importance of considering both patients' preferences and surgical indications when evaluating need and appropriateness of rates for surgery.

Occupational Distribution and Geographic Clustering of Deaths Certified To Be Cryptogenic Fibrosing Alveolitis in England and Wales

The etiology of cryptogenic fibrosing alveolitis (CFA) remains largely obscure, although a 1996 report suggested an increased risk from occupational exposure to metal and wood dusts. Using data from death certificates in England and Wales, we sought evidence of any relationship between occupation and CFA and of the extent of any temporospatial clustering of place of birth and place of death as possible evidence of a geographically related environmental factor. Data on occupation and address (postal code) were obtained from certificates of men and women dying as a result of CFA between 1981 and 1990 and were compared with national mortality statistics. Place of birth data were extracted from certificates for deaths between 1993 and 1995, the only available years, and were compared with national birth statistics. Standardized mortality ratios (SMRs) were raised (p<0.05) in the following four occupational groups: members of the armed forces (SMR, 217.8); miners and quarrymen (SMR, 142.0); service, sports, and recreation workers (SMR, 118.6); and electrical and electronic workers (SMR, 146.6). Of these four groups, the latter group might be worth testing in a future study. There was statistical evidence of geographic clustering in postal code sectors for the recorded place of death, but the high-rate areas were different in men and women. Deaths were increased for those subjects born in urban areas, although these did not follow a clear geographic pattern. Overall, these analyses provide little evidence of any important contribution from environmental factors to the etiology of CFA and suggest that more consideration be given to alternative concepts of causation.

沖縄県宮古島における空間γ線線量率の分布

The absorbed dose rate in air because of terrestrial gamma radiation in Miyako-jima, an island that is part of Okinawa Prefecture in the subtropical region of Japan, was estimated at 637 points by in situ measurements with spectrometers equipped with 3″φ×3″NaI (Tl) and 1″φ×2″NaI (Tl) scintillation detectors. The mean, minimum, and maximum dose rates were calculated to be about 79nGy/h, 3nGy/h, and 165nGy/h, respectively. The correlation of the dose rate and geology showed that the high-rate areas (>100nGy/h) and the distribution of the Holocene red soils (Onokoshi Clay) overlap each other. On the other hand, the low dose rates (<30nGy/h) were mainly found in an outcrop of the Pleistocene Ryukyu Limestone, the main geologic element in the foundation of the red soils. Recent studies (e. g., Inoue et al., 1993) concluded that most of the red soils were not residuals from the base rocks, but of eolian dust “Kosa (Yellow Sand)” origin. These results strongly indicate that the dose rate in Miyako-jima has been enhanced as a result of eolian deposits transported mainly from the arid region of China since the last glacial epoch.

Channel estimation method with interference reduction for high-rate personal area networks

A channel estimation technique with interference cancellation in a wireless personal area network system with complementary code keying signalling is described. The performance of the proposed coherent detector is compared with that of a non-coherent detector, and a significant performance improvement as a result of the self-interference cancellation feature is observed.