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Systematic review of treatments for atopic eczema.

BACKGROUND: Atopic eczema is the commonest inflammatory skin disease of childhood, affecting 15-20% of children in the UK at any one time. Adults make up about one-third of all community cases. Moderate-to-severe atopic eczema can have a profound effect on the quality of life for both sufferers and their families. In addition to the effects of intractable itching, skin damage, soreness, sleep loss and the social stigma of a visible skin disease, other factors such as frequent visits to doctors, special clothing and¿the need to constantly apply messy topical applications all add to the burden of disease. The cause of atopic eczema is unknown, though a genetic pre-disposition and a combination of allergic and non-allergic factors appear to be important in determining disease expression. Treatment of atopic eczema in the UK is characterised by a profusion of treatments aimed at disease control. The evidential basis of these treatments is often unclear. Most people with atopic eczema are managed in primary care where the least research has been done. OBJECTIVES: The objectives of this scoping review are two-fold. To produce an up-to-date coverage 'map' of randomised controlled trials (RCTs) of treatments of atopic eczema. To assist in making treatment recommendations by summarising the available RCT evidence using qualitative and quantitative methods. METHODS DATA SOURCES: Data sources included electronic searching of MEDLINE, EMBASE, the Cochrane Controlled Clinical Trials Register, the Cochrane Skin Group specialised register of trials, hand-searching of atopic eczema conference proceedings, follow-up of references in retrieved articles, contact with leading researchers and requests to relevant pharmaceutical companies. INCLUSION/EXCLUSION CRITERIA: Only RCTs of therapeutic agents used in the prevention and treatment of people with atopic eczema of any age were considered for inclusion. Only studies where a physician diagnosed atopic eczema or atopic dermatitis were included. DATA EXTRACTION: Data extraction was conducted by two observers onto abstraction forms, with discrepancies resolved by discussion. QUALITY ASSESSMENT: The quality assessment of retrieved RCTs included an assessment of: a clear description of method and concealment of allocation of randomisation, the degree to which assessors and participants were blinded to the study interventions, and whether all those originally randomised were included in the final main analysis. DATA SYNTHESIS: Where possible, quantitative pooling of similar RCTs was conducted using the Cochrane Collaboration's methods. Where statistical heterogeneity was found, sources of heterogeneity in terms of study participants, formulation or posology of intervention, and use of co-treatments were explored. Where pooling was not deemed to be appropriate, detailed descriptions of the study characteristics and main reported results were presented along with comments on study quality. RESULTS: A total of 1165 possible RCTs were retrieved in hard copy form for further scrutiny. Of these, 893 were excluded from further analysis because of lack of appropriate data. The 272 remaining RCTs of atopic eczema covered at least 47 different interventions, which could be broadly categorised into ten main groups. Quality of reporting was generally poor, and limited statistical pooling was possible only for oral cyclosporin, and only then after considerable data transformation. There was reasonable RCT evidence to support the use of oral cyclosporin, topical corticosteroids, psychological approaches and ultraviolet light therapy. There was insufficient evidence to make recommendations on maternal allergen avoidance for disease prevention, oral antihistamines, Chinese herbs, dietary restriction in established atopic eczema, homeopathy, house dust mite reduction, massage therapy, hypnotherapy, evening primrose oil, emollients, topical coal tar and topical doxepin. (ABSTRACT TRUNCATED)

Administration, Cutaneous↗

Using patients' records as a source of data.

This article discusses the use of patients' records as a data source. It examines the ethical issues involved in using patients' records, as well as their potential advantages and limitations.

Data Collection↗

New medications for use in patients with rheumatoid arthritis.

INTRODUCTION: Several new medications have become available to physicians for the treatment of patients with rheumatoid arthritis (RA). LEARNING OBJECTIVES: To familiarize the reader with these new medications, including their benefits and side effects. DATA SOURCES: Data sources include published articles regarding the use of these medications. Study selection includes available information obtained from an online literature search (Mayo Search) regarding these agents, with additional information from the manufactures and our pharmacy. CONCLUSION: The results of this review indicate that leftunomide (Arava) and etanercept (Enbrel) are useful new agents for treatment of patients with rheumatoid arthritis.

Anti-Inflammatory Agents, Non-Steroidal↗

Ascertainment of birth defects: the effect on completeness of adding a new source of data.

BACKGROUND: The Western Australian (WA) Birth Defects Registry aims for complete ascertainment of birth defects in WA, but the proportions of birth defects in rural areas and in Aboriginal children are lower than in metropolitan and non-Aboriginal children. The effect on ascertainment of adding data from the Rural Paediatric Service (RPS) was investigated. METHOD: A file of all cases of birth defects for children born 1980-1997 and recorded on the RPS database was linked to the Registry. RESULTS: The addition of this new data source had little effect on the overall prevalence of birth defects (an increase from 5.38 to 5.41%). There was a slightly greater effect on the prevalence of birth defects in rural residents (4.67%-4.76%) and Aboriginal children (4.55-4.78%), although the prevalence for each of these groups is still less than for metropolitan residents and non-Aboriginal infants, respectively. All major categories of birth defects were represented in the new cases and, in general, their addition made little difference to the prevalence of each category. The exception was fetal alcohol syndrome, which increased from 0.13 per 1000 to 0.18 per 1000 once the 21 new cases from the RPS were added. CONCLUSION: Complete ascertainment of birth defects is important in developing and evaluating preventive programs, and in investigating clusters of birth defects.

Congenital Abnormalities↗

Birthweight distribution at Korle-Bu Teaching Hospital, Ghana.

OBJECTIVES: To determine the birthweight distribution of singleton births at the Korle-Bu Teaching Hospital and to determine if selected socio-demographic and reproductive characteristics that are known to be associated with birthweight would show the association in our setting. DESIGN: A non-randomised cross-sectional survey of all deliveries within the study period. SETTING: Korle-Bu Teaching Hospital, a tertiary institution, delivering about 11,000 women a year. STUDY POPULATION: From 1st November to 12th December 1994, 866 singleton normally formed livebirths and fresh stillbirths were sequentially enrolled. DATA SOURCES: Data sources were the antenatal and delivery records of the subjects and an interviewer-administered questionnaire. RESULTS: The mean birthweight for the total sample was 3070 g +/- 616 g. One hundred and fifteen (13.3%) babies were low birthweight. The mean birthweight for those with reliable dates and born at term was 3262 g +/- 488.8 g. Multiple logistic regression analysis showed lack of antenatal malaria chemoprophylaxis and a history of previous low birthweight to be significantly associated with low birthweight. CONCLUSION: Although the mean birthweight of Korle-Bu babies was lower than those of USA and UK babies, it was comparable with those from other developing countries. Antenatal malaria chemoprophylaxis is a practical intervention that can produce an increase in mean birthweight and reduce the risk of low birthweight in our population.

Birth Weight↗

Enteric transmission of transfusion-transmitted virus.

OBJECTIVE: To detect the virus in the feces and sera of patients in an outbreak of enterically transmitted non-A, non-E hepatitis, and this review covers the epidemiologic features and experimental infection of this novel virus. DATA SOURCES: Data sources come from our own work on this subject, published and unpublished. STUDY SELECTION: Mainly our own work is included, and related literature is collected. RESULTS: In an outbreak of enterically transmitted non-A-E hepatitis among students, a total of 381 cases (60.7%) were documented. Viral fragments identical to transfusion transmitted virus (TTV) were detected in both serum and stool samples. Asymptomatic virus carriers among the staff had positive serum (32.1%) and feces (24.6%), clearly a potential source of infection. This viral infection prevalence in 2 remote villages in northern and southern China was 9.2% and 10.6%, respectively, suggesting that China is an endemic area. In this study, groups of 3 Rhesus monkeys were infected via oral or intravenous inoculation with patient feces. Two additional monkeys were infected by passage. The virus was detected in serum, peripheral blood mononuclear cell (PBMC), liver, spleen and small intestine, while the virus positive single strand, which might be a replicative intermediate, was only in liver, intestine and PBMC of all animals. CONCLUSIONS: This nonenveloped DNA virus might be transmitted both by blood and enteric routes. Considering its wide distribution and high prevalence, we suppose that nonparenteral transmission is more important.

Animals↗

An empirical study of economies of scope in home healthcare.

OBJECTIVE: To apply the economic theory of economies of scope to the home healthcare industry. DATA SOURCES: Data on 488 observations obtained from the Cost Report (HCFA Form 1728-86) of all Connecticut state-licensed, Medicare-certified home health agencies. STUDY DESIGN: The Cost Report was the primary source of data for this study. Information on total cost, scope, and other related factors was collected. Logarithmic and nonlinear regression analyses were used to identify factors related to scope and also to test for economies of scope. DATA COLLECTION METHOD: Data collected were both cross-sectional and time series (from 1988-1992). Data accuracy was verified using description of frequencies, measures of central tendency and variation, and a calculation package so that a computer calculation on the data could be compared with the agency's calculation. PRINCIPAL FINDINGS: It was determined that initially as scope increases, costs go down, thus proving economies of scope. For larger values of scope, it was determined that costs go up, proving diseconomies of scope. CONCLUSIONS: Many of the home health agencies included in this study provide more services than is cost effective given the economic theory of economies of scope.

Connecticut↗

Dose-response characteristics of cholesterol-lowering drug therapies: implications for treatment.

PURPOSE: To develop an optimal treatment strategy that reduces low-density lipoprotein (LDL) cholesterol levels and improves adherence to therapy by reviewing clinical trials that define the dose-response characteristics for 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), bile acid sequestrants, and niacin. DATA SOURCES: Data were obtained from a MEDLINE search of the English-language literature published from 1975 through November 1995 and from an extensive bibliography review. STUDY SELECTION: Controlled, clinical trials were reviewed if they evaluated 1) the effectiveness and toxicity of one LDL cholesterol-lowering agent (statins, bile acid sequestrants, or niacin, at two or more doses) or 2) monotherapy with two LDL cholesterol-lowering agents at defined doses used alone and in combination. Studies that had fewer than 10 patients in a treatment group or that selected patients on the basis of previous response to therapy were not included. DATA EXTRACTION: Trials were reviewed for overall methodology, inclusion and exclusion criteria, sources of bias, and outcomes. DATA SYNTHESIS: Dose-response relations for bile acid sequestrants and statins are nonlinear, and most of their LDL cholesterol-lowering effects can be obtained with lower doses. The few dose-response studies of niacin that have been done suggest that most of niacin's high-density lipoprotein cholesterol-increasing effect can also be achieved with relatively low doses, but higher doses are needed to substantially reduce LDL cholesterol levels. If bile acid sequestrants or niacin are added to statin therapy, the effect of combined therapy on LDL cholesterol levels is additive. CONCLUSION: The nonlinear dose-response relation of statins, bile acid sequestrants, and niacin and their additive LDL cholesterol-lowering effect when used together suggest a strategy for treating hypercholesterolemia that may optimize effectiveness while minimizing adverse effects and cost.

Anticholesteremic Agents↗

Factors that enhance continued trauma center participation in trauma systems.

OBJECTIVES: To examine hospital, trauma system, and reimbursement factors that offset the financial burdens of trauma care delivery and to assess how proposed Medicaid and Medicare budget cuts may affect the ability of hospitals to alleviate financial pressures related to trauma care delivery. DESIGN AND SETTING: In-depth interviews and data collection for trauma centers in 12 metropolitan areas with populations of 1 million or more. PARTICIPANTS: Seventy trauma centers in these large urban communities that indicated a continuing commitment to providing trauma services for the foreseeable future. MAIN OUTCOME MEASURES: Hospital, trauma system, and reimbursement characteristics that distinguish hospitals that are better able to alleviate the financial burdens of indigent trauma care and a financial analysis that assesses payment adequacy for different payers and overall financial outcomes. DATA SOURCES: Data from a variety of sources were obtained to measure the factors that affect the operation and financing of trauma centers: published and unpublished hospital data from the American Hospital Association; trauma center level, length of operation, and the availability of alternative centers from a recently published study; Health Care Financing Administration data on Medicare and Medicaid program characteristics; automobile insurance requirements; and patient discharge data. Most data are reflective of 1992. RESULTS: Public hospitals, teaching hospitals, and institutions receiving supplemental indigent care payments appear to be best able to mitigate the financial burdens of uncompensated trauma care, especially those with moderate indigent care loads. A detailed financial analysis found that private hospitals with trauma centers were near break-even in 1992 for trauma care delivery and public hospitals experienced financial losses. Proposals to reduce Medicaid and Medicare would create substantial reductions in hospital payments for hospital-wide patient care and trauma patients specifically. CONCLUSION: Proposed Medicaid and Medicare payment cuts are likely to eliminate the delicate financial balance that many urban hospitals have achieved in providing trauma care. The erosion in funding from public programs may portend a new wave of trauma center closures as hospitals seek to deal with reduced reimbursement by eliminating unprofitable services.

Diagnosis-Related Groups↗

Potential health effects of greenhouse effect and ozone layer depletion in Australia.

OBJECTIVE: To identify potential health effects of the greenhouse effect and ozone layer depletion in Australia. DATA SOURCES: Data were derived from a number of sources: (i) published articles accessed from relevant databases in the disciplines of health, public health and climatology over the past 20 years; (ii) published conference proceedings, review monographs and government reports covering the topic; (iii) a survey of experts in public health and climatology/geography (150 individuals were surveyed in the first phase with a 63% response rate); and (iv) a consensus conference in which 22 invited experts reviewed the results of the literature review and survey and a second conference in which 18 senior members of the health bureaucracy and public health profession considered the implications of the findings. STUDY SELECTION: Over 200 published articles or monographs were reviewed. Criteria for selection were whether the papers contributed information to the objectives of the review. DATA EXTRACTION: Because of the nature of the problem under investigation, predictions based on reasonable scientific assumptions were the major content of the review rather than conclusions based on scientific research. DATA SYNTHESIS: The major predicted health effects of long-term climatic change in Australia are skin and eye damage from increased ultraviolet radiation exposure, increased incidence of some respiratory diseases, vector-borne and water-borne diseases, and the social and physical effects of natural hazards and social and economic restructuring. The most vulnerable groups include the aged, the very young, the chronically ill, those living in poorly designed neighbourhoods and those working in outdoor occupations or heavy industry. CONCLUSIONS: The potential effects on health of long-term climatic change cover the broad spectrum of public health concerns. Detailed predictions of likely problems in specific geographic areas are not yet possible, but progressive development of such predictive capability is a high priority. Doctors will have an increasingly important role in monitoring local health status and participating in disease prevention and surveillance programmes.

Animals↗

Longitudinal patterns of medical service use and costs among people with AIDS.

OBJECTIVE: This study examines the effect of race, HIV transmission group, and decedent status on the use and cost of inpatient and outpatient care among people with AIDS. DATA SOURCES: Data come from 914 people with AIDS who were receiving services in nine cities across the United States in 1990-1991 and who indicated that a hospital clinic was their usual source of care. Review of hospital medical and billing records provided data on use and costs of medical services over an 18-month period. Vital status was determined from hospital records and death certificates. STUDY DESIGN: Data from each respondent were aggregated into three-month intervals, beginning with the last quarter of data and working backward. Regression analyses using random-effect models and generalized estimating equations were conducted to assess temporal patterns of inpatient and outpatient use and costs. PRINCIPAL FINDINGS: Inpatient utilization and costs were higher for decedents than for nondecedents. However, differences between decedents and nondecedents varied as a function of race. Nonwhites had more inpatient use and higher costs than whites, but lower outpatient use, and these differences were greater among decedents. Inpatient nights and costs rose sharply in the six months prior to death. Outpatient use and costs did not display as strong a temporal trend. CONCLUSIONS: Much of the cost of treating HIV infection is concentrated in the period immediately preceding death. The intensity of service use in the terminal period should be considered when developing estimates of annual costs of care and when designing programs to provide community-based treatment.

Acquired Immunodeficiency Syndrome↗

Inhaled respiratory medications and the use of chlorofluorocarbons (CFCs). Thoracic Society of Australia and New Zealand.

OBJECTIVE: To assess the use of chlorofluorocarbons (CFCs) in metered-dose aerosols against the background of community concerns regarding the adverse environmental effects of CFCs. DATA SOURCES: Data on the constituents of currently available metered-dose aerosols were supplied by the manufacturers, and details of chemistry and safety were obtained from monographs and papers published in the medical literature. STUDY SELECTION: Five papers, published in the early 1970s when metered-dose aerosols first became popular, were reviewed for safety data on CFCs. Several chapters in monographs were searched for data on the nature and function of CFCs in metered-dose aerosols, and five papers were the source of information on alternatives to CFCs as vehicles for the delivery of inhaled respiratory drugs. DATA SYNTHESIS: The medical use of CFCs accounts for only 1.5% of the total production in Australia, the majority being used for refrigeration, air-conditioning and other commercial or industrial purposes. The physicochemical properties of CFCs are such that they function as a suitable storage medium for active drugs within the canister and as an ideal vehicle for drug delivery. Approximately 20 s after inhalation of a clinically recommended dose of a bronchodilator metered-dose aerosol, CFCs are detectable in the blood, but the concentrations decline rapidly (half-life less than 40 s). Although CFCs have been shown to sensitise the myocardium to the arrhythmogenic effects of catecholamines in experimental animals, the requisite concentrations can only be achieved by patients if they inhale from a canister on every breath for approximately 20 successive breaths. CONCLUSIONS: CFCs used in metered-dose aerosols are an effective storage medium and a convenient vehicle for drug delivery. They are non-toxic--unless amounts far in excess of the clinically recommended doses are used, when arrhythmogenic effects may occur. The medical use of CFCs has minimal environmental impact compared with their industrial and commercial use. Dry powder delivery systems offer an alternative approach, and future research will yield nonozone-depleting CFCs suitable for replacing those in current metered-dose aerosols.

Administration, Inhalation↗

Primary care, self-rated health, and reductions in social disparities in health.

OBJECTIVE: To examine the extent to which good primary-care experience attenuates the adverse association of income inequality with self-reported health. DATA SOURCES: Data for the study were drawn from the Robert Wood Johnson Foundation sponsored 1996-1997 Community Tracking Study (CTS) Household Survey and state indicators of income inequality and primary care. STUDY DESIGN: Cross-sectional, mixed-level analysis on individuals with a primary-care physician as their usual source of care. The analyses were weighted to represent the civilian noninstitutionalized population of the continental United States. DATA COLLECTION/EXTRACTION METHODS: Principal component factor analysis was used to explore the stricture of the primary-care indicators and examine their construct validity. Income inequality for the state in which the community is located was measured by the Gini coefficient, calculated using income distribution data from the 1996 current population survey. Stratified analyses compared proportion of individuals reporting had health and feeling depressed with those with good and bad primary-care experiences for each of the four income-inequality strata. A set of logistic regressions were performed to examine the relation between primary-care experience, income inequality, and self-rated health. PRINCIPAL FINDINGS: Good primary-care experience, in particular enhanced accessibility and continuity, was associated with better self-reported health both generally and mentally. Good primary-care experience was able to reduce the adverse association of income inequality with general health although not with mental health, and was especially beneficial in areas with highest income inequality. Socioeconomic status attenuated, but did not eliminate, the effect of primary-care experience on health. In conclusion, good primary-care experience is associated not only with improved self-rated overall and mental health but also with reductions in disparities between more- and less-disadvantaged communities in ratings of overall health.

Adult↗

The poisoned patient with altered consciousness. Controversies in the use of a 'coma cocktail'.

OBJECTIVE: In the assessment and management of the potentially poisoned patient with altered consciousness, the most consequential and controversial interventions occur during the first 5 minutes of care. In this review article, the risks and benefits of standard diagnostic and therapeutic interventions are presented to guide clinicians through this critical period of decision making. DATA SOURCES: Data for discussion were obtained from a search of English-language publications referenced on MEDLINE for the years 1966 to 1994. Older literature was included when pertinent. Search terms included poisoning, overdose, toxicity, naloxone, glucose, thiamine, and flumazenil. STUDY SELECTION: Only large trials were used for determinations of diagnostic utility and efficacy. Small trials, case series, and case reports were reviewed extensively for adverse effects. DATA EXTRACTION AND SYNTHESIS: Trials were reviewed for overall methodology, inclusion and exclusion criteria, sources of bias, and outcome. CONCLUSION: Analysis favors empirical administration of hypertonic dextrose and thiamine hydrochloride to patients with altered consciousness. Although rapid reagent test strips can be used to guide this therapy, they are not infallible, and they fail to recognize clinical hypoglycemia that may occur without numerical hypoglycemia. Administration of naloxone hydrochloride should be reserved for patients with signs and symptoms of opioid intoxication. Flumazenil is best left for reversal of therapeutic conscious sedation and rare select cases of benzodiazepine overdose.

Consciousness↗

Estimating the population prevalence of injection drug use and infection with human immunodeficiency virus among injection drug users in Glasgow, Scotland.

Although data on the prevalence of injection drug use are an essential prerequisite for estimating the number of individuals infected with the human immunodeficiency virus (HIV), there have been few attempts to utilize statistical methods of population estimation based on multiple data sources. Data on 3,670 cases (2,866 individuals) were obtained from the HIV test register, drug treatment agencies, police records, and needle and syringe exchanges in Glasgow, Scotland, in 1990. Log-linear analysis was used to model the number of individuals in each of the sources. The model incorporating dependency among the three health care agencies (HIV test, drug treatment, and needle exchange) and independence of the police sample fitted the data well, with a residual chi 2 value of 2.9 (6 df). The expected value of the missing cell corresponding to absence from all four samples was 5,628, yielding an overall estimate of 8,494 injectors (95% confidence interval (CI) 7,491-9,721), for a prevalence rate of 1.35% for people aged 15-55 years in Glasgow during 1990. The high ratio of known to unknown injectors (1:2) resulted from the extensive coverage of known injectors and the relatively high level of overlap between the combined health care agency sample and the police sample. While further analysis demonstrated that the probability of appearing in the four samples varied by age and sex, heterogeneity in the population did not affect the choice of model or substantially alter the estimates for the total number of unknown injectors. A concurrent study of a community-wide sample of 503 injectors resulted in an HIV prevalence rate of 1.1% (95% CI 0.4-2.5%). The results of these studies were combined to produce a further estimate of 93 HIV-infected current injectors in Glasgow (95% CI 33-214).

Adolescent↗

Evaluation of a new generation of oral contraceptives. The Advisory Board for the New Progestins.

OBJECTIVE: To assess the differences and similarities in efficacy, safety, and metabolic effects of oral contraceptives (OCs) containing the new progestins desogestrel, gestodene, and norgestimate. All formulations reviewed contained no more than 35 micrograms ethinyl estradiol. DATA SOURCES: Data were reported from approximately 100 published reports, dating from 1980, of comparative and noncomparative clinical studies on phasic and fixed-dose preparations culled from computer searches of several sources, including MEDLINE and Excerpta Medica. METHODS OF STUDY SELECTION: An attempt was made to select the most meaningful studies in terms of length, size, methodology, and quality of description. All clinical studies were considered; in general, review articles were not. Some preclinical studies were also included. No abstracts were used. DATA EXTRACTION AND SYNTHESIS: The indices chosen for examination were contraceptive efficacy, cycle control, coagulation, carbohydrate and lipid metabolism, and androgenicity. CONCLUSIONS: The new formulations were found to be comparable in efficacy to each other and to established agents. They also appeared to be less androgenic than current OCs and to have less impact on carbohydrate and lipoprotein metabolism. Cycle control was similar to that of older products. Changes in coagulation-promoting and antithrombotic factors were minor. Clinical relevance of the results could not be determined because of small sample size and methodologic differences between studies.

Androgens↗

Economic expansion is a major determinant of physician supply and utilization.

OBJECTIVE: To assess the relationship between levels of economic development and the supply and utilization of physicians. DATA SOURCES: Data were obtained from the American Medical Association, American Osteopathic Assocation, Organization for Economic Cooperation and Development (OECD), Bureau of Health Professions, Bureau of Labor Statistics, Bureau of Economic Analysis, Census Bureau, Health Care Financing Administration, and historical sources. STUDY DESIGN: Economic development, expressed as real per capita gross domestic product (GDP) or personal income, was correlated with per capita health care labor and physician supply within countries and states over periods of time spanning 25-70 years and across countries, states, and metropolitan statistical areas (MSAs) at multiple points in time over periods of up to 30 years. Longitudinal data were analyzed in four complementary ways: (1) simple univariate regressions; (2) regressions in which temporal trends were partialled out; (3) time series comparing percentage differences across segments of time; and (4) a bivariate Granger causality test. Cross-sectional data were assessed at multiple time points by means of univariate regression analyses. PRINCIPAL FINDINGS: Under each analytic scenario, physician supply correlated with differences in GDP or personal income. Longitudinal correlations were associated with temporal lags of approximately 5 years for health employment and 10 years for changes in physician supply. The magnitude of changes in per capita physician supply in the United States was equivalent to differences of approximately 0.75 percent for each 1.0 percent difference in GDP. The greatest effects of economic expansion were on the medical specialties, whereas the surgical and hospital-based specialties were affected to a lesser degree, and levels of economic expansion had little influence on family/general practice. CONCLUSIONS: Economic expansion has a strong, lagged relationship with changes in physician supply. This suggests that economic projections could serve as a gauge for projecting the future utilization of physician services.

Cross-Sectional Studies↗

Treatment of vitamin b(12)-deficiency anemia: oral versus parenteral therapy.

OBJECTIVE: To evaluate the use of oral cyanocobalamin therapy in the treatment of cobalamin (vitamin B(12))-deficient anemia. DATA SOURCES: Primary and review articles were identified by MEDLINE search (1966-May 2000) and through secondary sources. DATA SYNTHESIS: Cobalamin-deficient anemia is among the most common diagnoses in older populations. Cobalamin-deficient anemia may be diagnosed as pernicious anemia, resulting from the lack of intrinsic factor required for cobalamin absorption or as protein malabsorption from the inability to displace cobalamin from protein food sources. Several studies provide evidence that daily oral cyanocobalamin as opposed to monthly parenteral formulations may adequately treat both types of cobalamin-deficient anemias. CONCLUSIONS: Daily oral cyanocobalamin at doses of 1000-2000 microg can be used for treatment in most cobalamin-deficient patients who can tolerate oral supplementation. There are inadequate data at the present time to support the use of oral cyanocobalamin replacement in patients with severe neurologic involvement.

Administration, Oral↗