Geographic Variation In Rates Research Articles

Socioeconomic variation in discretionary and mandatory hospitalization of infants: an ecologic analysis.

To examine geographic variation in rates of infant hospitalization for diagnoses classified by type of hospitalization decision in Monroe County (Rochester), New York. Study design was cross-sectional and ecologic. International Classification of Diseases (ICD) codes were used to categorize all 7883 hospitalizations for infants (age, <24 months) beyond the newborn period between 1985 and 1991. Postal zip codes defined socioeconomic areas as inner-city, other urban, and suburban for the population at risk. In 1990, inner-city infants included 62% black and 65% Medicaid-covered infants, whereas suburban infants included 3% black and 6% covered by Medicaid. Hospitalization rates were compared among the three socioeconomic areas. Overall hospitalization rate was 50.3 per 1000 child years. Admissions classified as discretionary accounted for 59% of these, followed by those classified as mandatory, 18%; sometime (congenital heart disease, cleft palate), 15%; discretionary surgery (inguinal hernia, tonsillectomy/adenoidectomy), 6%; and unlikely to need admission, 2%. A stepwise, socioeconomic gradient in hospitalization was found, with rates of 38.1, 51.3, and 82.9 per 1000 child-years, respectively, for suburban, other urban, and inner-city areas. Rates for discretionary, unlikely, and mandatory admissions followed this gradient. Using the odds for hospitalization of suburban infants as the base odds, the odds ratio for discretionary hospitalization for inner-city infants was 2.88 (95% confidence interval [CI], 2.69 to 3. 08) and that for mandatory hospitalization was 2.20 (95% CI, 1.94 to 2.49). In multiple regression analysis, low education level of mothers explained 81% of the variance in discretionary hospitalization rate. Although the per capita rate of hospital care of inner-city infants was more than twofold greater than that for suburban infants, potential for reducing this difference is suggested by the fact that discretionary admissions accounted for 78. 9% of this difference, whereas mandatory admissions accounted for 17. 7% of the difference. The hospitalization rate for inner-city infants is much greater than that for suburban infants. A substantial portion of the difference, namely that attributable to mandatory admissions, reflected higher rates of serious illness. Differences attributable to discretionary admissions may reflect higher rates of serious illness to some extent, but also appear to reflect less effective health services to a substantial degree.

Geographical variations in rates of ophthalmic surgery

Geographical variations in rates of ophthalmic surgery

Geographical variations in rates of ophthalmic surgery.

Geographical variations in health care are common. There is, however, no simple explanation for why they arise. Variations in rates of ophthalmic surgery in the population aged 65 and over were investigated, with the aim of determining their cause. Routine data sources were used to obtain the 1991-2 age and sex standardised rates for English health districts with an ophthalmic unit. Weighted least squares regression was used to study the relation between these rates and various factors describing the population and the provision of care. Surgery rates varied more than threefold. High rates of surgery were associated with high throughput and bed numbers (both p < 0.001), high proportions of day case surgery (p < 0.001), long waiting lists (p < 0.001), and a high number of theatre sessions (p = 0.002). Conversely, a high percentage of emergency admissions was associated with lower rates of surgery (p = 0.004). These six variables accounted for 58% of the variation. Geographical variations were found to exist, less than two thirds being explained by differences in the provision of care. The remaining variation may partly be attributed to private practice and the lack of consensus for many ophthalmic procedures (the 'surgical signature'), including a lowering of the threshold for surgery. These findings have implications for the planning of ophthalmic services.

Geographic variation in rate of schizophrenia by place of birth vs place at onset of illness in rural Ireland, and its gender characteristics

Geographic variation in rate of schizophrenia by place of birth vs place at onset of illness in rural Ireland, and its gender characteristics

Rational Prescribing and Interpractitioner Variation:A Multilevel Approach

There are marked geographical variations in rates of medical and surgical intervention at every level of aggregation and in every aspect of medical practice. These data raise a range of important theoretical, methodological, and policy issues. Much the same pattern of variation characterizes the prescription and consumption of therapeutic drugs. Data from a survey of general practice in New Zealand confirm the existence of extensive variability in prescribing. Multilevel techniques are deployed to isolate the specific interpractitioner element in this variability. Controlling for patient, diagnostic, and practitioner variables improves the predictive power of the model but does not reduce the extent of interpractitioner variability in prescribing rates. The existence of such variability raises questions about the role of clinical uncertainty and professional autonomy in the promotion of rational therapeutics in medical practice.

The Back Pain Outcome Assessment Team:

Objectives: To describe the federal initiative in outcomes research, the organization and structor of a Patient Outcomes Research Team [PORT] concerned with low back pain, and the early progress of this research team. Findings: Back pain is a leading reason for physician visits, hospitalization, and work disability. However, there is a paucity of valid evidence to support most current methods of treating spine disorders. This PORT was funded to study geographic variation in the use of back surgery and to better characterize its outcomes; evaluate the reasons for nonsurgical hospitalization for back pain; examine the accuracy and optimal sequencing of expensive diagnostic tests; and disseminate information to clinicians and patients to improve the process of care. This effort requires a multidisciplinary team of clinicans and methodologist, and a network of government and professional organizations concerned about the problem of low back pain. The team has documented wide geographic variations in rates of ...

Rates of soil development from four soil chronosequences in the southern Great Basin

Four soil chronosequences in the southern Great Basin were examined in order to study and quantify soil development during the Quaternary. Soils of all four areas are developed in gravelly alluvial fans in semiarid climates with 8 to 40 cm mean annual precipitation. Lithologies of alluvium are granite-gneiss at Silver Lake, granite and basalt at Cima Volcanic Field, limestone at Kyle Canyon, and siliceous volcanic rocks at Fortymile Wash. Ages of the soils are approximated from several radiometric and experimental techniques, and rates are assessed using a conservative mathematical approach. Average rates for Holocene soils at Silver Lake are about 10 times higher than for Pleistocene soils at Kyle Canyon and Fortymile Wash, based on limited age control. Holocene soils in all four areas appear to develop at similar rates, and Pleistocene soils at Kyle Canyon and Fortymile Wash may differ by only a factor of 2 to 4. Over time spans of several millennia, a preferred model for the age curves is not linear but may be exponential or parabolic, in which rates decrease with increasing age. These preliminary results imply that the geographical variation in rates within the southern Great Basin-Mojave region may be much less significant than temporal variation in rates of soil development. The reasons for temporal variation in rates and processes of soil development are complexly linked to climatic change and related changes in water and dust, erosional history, and internally driven chemical and physical processes.

Further Issues in Small Area Variations Analysis

In this article, I examine Wennberg's "practice style" hypothesis and the literature on variations among small areas. According to Wennberg, geographic variations in rates of per capita use for many clinical procedures arise mainly from differences over what constitutes appropriate care. I show, however, that the role of practice style in explaining variations among areas has not been clearly demonstrated. I also argue that the practice style hypothesis can neither be established nor refuted by the methods traditionally used to study small areas and, moreover, that inferences about practice style variations cannot be drawn from differences among areas in their rates of use. I thus conclude that more research at the micro level in the practice patterns of the individual physician is needed before major health care initiatives based on small area methodology are undertaken.

Unexpected geographic variation in rates of hospitalization for patients who have fracture of the hip. Medicare enrollees in the United States.

With the use of data from hospitals for fiscal year 1985, we calculated the rates of hospitalization for fracture of the hip, by state of residence, for all enrollees in Medicare who were sixty-five years old or older; we adjusted for age and race. The rate of fracture of the hip was highest in the South and lowest in the Northeast, especially in women. The cause of this difference is not known.

Soil development on stable landforms and implications for landscape studies

Abstract Soil development parameters include a wide variety of morphological, chemical, and mineralogical parameters, but some of the best indicators of time and surface stability are derived from field morphology. Over long time-spans, the most common time function for soil development is exponential or logarithmic, in which rates decrease with increasing age. Over shorter time-spans in semi-arid and moister climates, Holocene and Pleistocene soil development functions appear as linear segments, with Holocene rates about 10 to 50 times those of Pleistocene rates. In contrast to significant temporal variation in rates, geographical variation in rates within (a) the southern Great Basin and (b) the east Central Valley of California is on the order of 2 or 3 times. When comparing soil development indices of the semi-arid Great Basin to those of moister central California, Holocene rates are similar, but Pleistocene rates are more than 10 times slower in the Great Basin. In a range of climatic settings, the reasons for declining rates over time are several and are complexly related to erosional history, fluxes in water and dust related to climatic changes, rates of primary mineral dissolution, and intrinsic soil processes.

ABO blood group and ischaemic heart disease in British men.

To establish whether ABO blood group is related to ischaemic heart disease on an individual and geographic basis in Britain. Prospective study of 7662 men with known ABO blood group selected from age-sex registers in general practices in 24 British towns. ABO blood group, standard cardiovascular risk factors, social class, and presence or absence of ischaemic heart disease determined at entry to study. Eight year follow up of fatal and nonfatal ischaemic heart disease events achieved for 99% of study population. Towns with a higher prevalence of blood group O had higher incidences of ischaemic heart disease. In individual subjects, however, the incidence of ischaemic heart disease was higher in those with group A than in those with other blood groups (relative risk 1.21, 95% confidence limits 1.01 to 1.46). Total serum cholesterol concentration was slightly higher in subjects of blood group A. No other cardiovascular risk factor (including social class) was related to blood group. Blood group A is related to the incidence of ischaemic heart disease in individual subjects. Geographic differences in the distribution of ABO blood groups do not explain geographic variation in rates of ischaemic heart disease in Britain. The findings do not support the view that ABO blood group and social class are related.

Chromosome abnormalities in older women by maternal age: Evaluation of regression‐derived rates in chorionic villus biopsy specimens

Maternal age-specific rates of chromosome abnormalities in women undergoing chorionic villus sampling (CVS) were evaluated. These were rates derived from regression equations of the form rate = ln(b[age] + c) where age varied from 35 to 48 years; and b and c are parameters. For Down syndrome (47, + 21), b = 0.29 and c = -15.53; for other nonmosaic abnormalities, b = 0.25 and c = -14.11; and, for all abnormalities, b = 0.27 and c = -14.22. The predicted rates per 1,000 varied, respectively, from 4.2, 4.6, and 8.8 at age 35 years to 180.0, 120.0, and 300.0 at age 48 years. The predicted numbers of abnormalities were compared with those observed in an overlapping data set reported in the literature. For 47, + 21, the ratio of observed (O) to expected (E) numbers was 54/56.4 = 0.96, suggesting that these rates are at least not grossly erroneous. For non-47, + 21 chromosome abnormalities, the ratio of O to E was 66/51.1 = 1.29. The possibility of geographic variation in rates of non-47, + 21 chromosome abnormalities cannot be dismissed. Finally, if 1) the regression derived rates are correct, 2) there is no difference in selective loss of chromosome abnormalities between younger and older mothers, and 3) the ratio of rates at ages 35 and 40 years to those in the women of all ages are the same for all abnormalities at CVS as for 47, + 21 in live births, then the proportion of all women with viable conceptuses at time of CVS who have an embryo or fetus with cytogenetic abnormality is 3.8-4.4 per 1,000 conceptuses.

The Rate Burden: An Accounting Framework for Assessing the Effect of Local Taxes on Business

TYLER P., MOORE B. C. and RHODES J. (1988) The rate burden: an accounting framework for assessing the effect of local taxes on business, Reg. Studies 22, 387–398. During recent years there has been considerable interest in the effects which non-domestic rates (the local business tax) may be having on the competitiveness of British industry. Most discussion has been poorly informed because of the lack of an accounting framework with which to assess the extent of geographical variations in rates on local firms in terms of an economically meaningful variable. This paper provides such a framework and uses it to describe the extent of geographical variations in the rate burden arising from the present system of rates in the United Kingdom. The framework is also used to assess the consequences of alternative tax regimes, most notably the proposal for a unified business rate determined by central government. One advantage of the approach described is that it allows the separate identification of the effects of geographical variations in the tax rate. TYLER P., MOORE B. C. et RHODES J. (1988) Le poids de la fiscalité: un plan comptable pour évaluer l'impact des impôts locaux sur les entreprises, Reg. Studies 22, 387–398. Au cours des dernières années les effets de la taxe professionnelle sur la compétitivité de l'industrie britannique ont attiré beaucoup d'attention. La qualité du débat a souffert vu le manque d'un plan comptable afin d'évaluer l'ampleur des variations géographiques des taxes en fonction d'une variable économique révélatrice. Cet article a pour but de fournir un tel plan et s'en sert pour présenter l'ampleur des variations géographiques du poids fiscal qui remontent au système d'impôts en vigueur au Royaume-Uni. On se sert aussi du plan afin d'évaluer l'impact d'autres systèmes, notamment la proposition en faveur d'une seule taxe professionnelle déterminée par le gouvernement. Un avantage de la façon présentée c'est qu'elle permet l'identification indépendante des effets d'une variation géographique du taux d'imposition. TYLER P., MOORE B. C. und RHODES J. (1988) Die Steuerlast: ein Berechnungssystem zur Schätzung der Auswirkung lokaler Steuern auf das Geschäftsleben, Reg. Studies 22, 387–398. In den letzten Jahren ist den Auswirkungen beträchtliches Interesse entgegengebracht worden, die nicht auf Haushalte bezogene Steuern (örtliche Besteuerung von Geschäften) möglicherweise auf die Wettbewerbsfähigkeit der britischen Industrie ausüben. Die Diskussion wurde grössenteils auf der Grundlage mangelnder Information geführt, da ein Berechnungssystem zur Schätzung des Ausmasses geographischer Abweichungen in der Besteuerung ortsansässiger Firmen im Sinne einer wirtschaftlich brauchbaren Veränderlichen fehlt. Diese Abhandlung liefert solch ein System und benutzt es zur Beschreibung geographischer Abweichungen der Steuerlast, die durch das gegenwärtige Steuersystem des Vereinigten Königreichs entstehen. Das System wird auch zur Veranschlagung der Folgen alternativer Besteuerungsverfahren benutzt, vor allem denen eines Vorschlags zur einheitlichen Besteuerung von Geschäften, die von der obersten Regierungsbehörde festzusetzen wäre. Ein Vorteil der beschriebenen Handhabung ist, dass sie die getrennte Identifizierung der Auswirkung geographischer Schwankungen der Besteuerungsrate gestattet.

Geographical Variations in Use of Surgery for Glue Ear

Study of geographical variations in the rate of surgery for glue ear reveals striking differences both between English health regions and between health districts. There are two-fold differences between regions and up to seven-fold differences between districts. Analysis of these differences at different levels of population aggregation reveals that professional uncertainty about the indications and value of surgery for this condition is the major factor responsible. In addition, the availability of otolaryngologists influences the surgical rate at district though not at regional level. The method used in this study is unable to determine the part played by geographical variation in patient expectation and morbidity rate. In contrast to the lack of consensus among otolaryngologists regarding the use of surgery for glue ear, there appears to be a high degree of agreement as regards tonsillectomy. The latter has coincided with the end of the decline in the tonsillectomy rate in the late 1970s.

Assessing medical practices through PSRO cooperative studies, an evaluation of Cesarean births in nine PSRO areas.

Nine Professional Standards Review Organizations jointly conducted an areawide medical care evaluation study of Cesarean births. Of 5,002 Cesarean births studied in 158 hospitals, only 1.1 per cent were judged to be unjustified procedures by local physician peer review. Although there was substantial geographic variation in rates of Cesarean birth (11.0%-18.3 per cent), no statistically significant pattern of variation was identified. Maternal outcomes and infant outcomes were generally good. This study demonstrates the potential for use of PSRO data in studying major issues in health care, as well as the practical constraints of such studies.

Diet and cancer of endocrine target organs

The role of diet in the etiology of cancer of the breast and endometrium is considered. Geographic variation in rates, effects of migration, consequences of exogenous hormone use, and other epidemiologic factors are reviewed. Cancer of the endometrium is related to diet probably through simple caloric excess. The excess is reflected in obesity and the consequent overproduction of estrone, a natural but carcinogenic human estrogen. Diet may also influence breast cancer risk somewhat through the same mechanism. But this mechanism probably would not explain a large proportion of the disease. It is possible that, in addition, some specific dietary factor, for example, saturated fat, is causally related to breast cancer. Such a relationship would probably be mediated through an endocrine mechanism.