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PubMedDate not supplied

The impact of development and population policies on fertility in India.

This article examines the impact of development and population policies on fertility decline and regional variations in India during the 1970s. Indicators of development at the household level include female literacy and education, infant mortality, and poverty; at the village level they include availability of such social services as schools, medical facilities, and transportation and communication facilities. Multiple regression analysis of data aggregated at the state level demonstrates that conditions conducive to fertility decline include high adult female literacy and low infant mortality as indicators of social development, and high contraceptive use and, to a lesser extent, high female age at marriage as proximate determinants of fertility. There are reasons to believe that India's national family planning program contributed to the decline in fertility observed since the 1960s. The pace of fertility decline in the future will depend upon the pace of infant mortality decline, enhancement in female education, and improvements in family planning programs.

Birth Rate↗

PubMed1977

[Comparative evaluation of methods for predicting fetal lung maturity based on serial amniotic fluid tests (author's transl)].

12 pregnant females in the last trimester were subjected to serial amniocentesis. Although there was medical indication for amniocentesis the pregnancies were normal. All samples were evaluated with four different methods. We used two physical (Wilhelmy balance and foam test) and two chemical (L/S ratio densitometrically and planimetrically measured) methods. The Curves of individual pregnancies were compared with the reference values of 109 samples of amniotic liquid of uncomplicated pregnancies. Reference values for the various techniques reported in the literature are generally based on aggregate data collected from a number of pregnant females, which are then consolidated to obtain mean values for each gestational week. We found a continuous rise of all parameters, both in the reference value and in eight individual pregnancies. Besides we found a strikingly extraordinary run of the curves in four individual pregnancies. Here we recognized a rapid ascent and descent of surfactant concentration within short periods, which were not identical with the reference values. All four methods showed results with a statistical significant conformity, only the foam test showed a little lower significance.

Amniotic Fluid↗

PubMed1981

Context is important but it does not explain everything: a comment on "Matching performance and the similarity structure of the stimulus set" by Crist.

Crist's experiments provide convincing evidence of the importance of context in letter-matching tasks. His detailed analysis also demonstrates how the reporting of central tendency measures on data aggregated over different stimuli can sometimes lead to an oversimplified view of the processes involved. His rationale for the experiments and his theoretical treatment of his results are criticized in this review, however, as unnecessarily polarizing the analytic and contextual views of perceptual matching and as overstating the case for context as a sufficient explanatory construct. Crist's results suggest both general and specific contextual similarity effects; a possible theoretical account is outlined.

Discrimination Learning↗

PubMed1981

Identification of supplier induced demand in the health care sector.

This paper explores the issues and pitfalls encountered when attempting to test empirically the hypothesis that physician, hospital, or any other input supply level induces increasing demand for health services in the strict sense of demand shift and, through that, increased demand for the input in question. Evidence is presented which suggests that an empirical test of the supplier induced demand (SID) hypothesis of the type traditionally performed may not in fact be feasible with cross-sectional aggregate data such as is usually used.

Economics, Hospital↗

PubMed1980

Demographic factors in the disability determination process: a logistic approach.

Identifying the demographic factors that affect the likelihood of being allowed disability insurance benefits under the social security program is important in assessing the operation of that program and has been the focus of continuing research. Previous studies in this area, which have been limited to cross-tabular analyses of aggregated data and the examination of a few variables at a time, have uncovered apparently sizable differences in the probability of allowance by age, sex, race, and other demographic characteristics. This article uses a much more rigorous statistical technique--a logit maximum likelihood procedure--to examine the same question. That technique permits exploration of the relationship between a particular characteristic and the probability of allowance while controlling for the effect of other characteristics considered in the analysis. The findings show that cardiovascular primary diagnoses had a higher probability of allowance than did almost all other primary diagnoses. Mobility restrictions, older age at the onset of disability, and residence in States with temporary disability programs also were associated with a higher probability of allowance. Applicants who were black or from the South were found to have a lower probability of allowance. In general, those results applied to both men and women.

Demography↗

PubMed1980

Geographical distribution and recent changes in world supply of vitamin A.

Deficiency of vitamin A mainly affects infants and children up to the age of five years, and is often associated with protein-energy deficiency. The earliest symptom is night blindness. The most serious clinical manifestation is xerophthalmia which, depending upon the severity of the deficiency, may lead to partial or total blindness. Hypovitaminosis A is in fact a major cause of preventable blindness and must therefore be considered a serious public health problem. Hypovitaminosis A occurs in many developing countries and is particularly prevalent in South and East Asia. While the incidence and degree of severity varies from country to country, the population groups most affected are those of low socioeconomic status, usually with defective diets and living in poor sanitary environments. Poor dietary intake, however, appears to be the principal factor. The analysis that follows assesses the dynamics of the potential per caput supply situation as revealed by aggregate data at national level.

Asia↗

PubMed1995

Assessment of the completeness and accuracy of computer medical records in four practices committed to recording data on computer.

BACKGROUND: General practice computer databases are being increasingly seen as a source of data for public health monitoring and commissioning. Such ambitions depend on routine clinical data being recorded with acceptable completeness and accuracy. AIM: The aim of this study was to assess the completeness and accuracy of the computer medical records in four high-recording general practices. METHOD: Four general practices in the Trent Region that use the EMIS computer system, and were known to be high recorders of clinical data on their computer databases, were selected. A retrospective analysis of the computer records, a prospective comparison of a sample of computer records with manual records, and a prospective comparison between videorecorded consultations and their manual and computer records were undertaken. RESULTS: Checks for completeness in computer recording of diabetes mellitus and glaucoma showed high levels of accurate recording, 97% and 92% respectively. Prevalence rates between practices were reasonably comparable. No practice consistently, across 10 diagnoses, recorded prevalences higher or lower than the other practices; those diagnoses with recognized objective diagnostic criteria were recorded with a more consistent prevalence than those without. Lifestyle data recording was low; overall, smoking habits and alcohol consumption were recorded for 52% and 38% of patients aged over 16 years, respectively. Comparison of the manual records with the computer records showed that the computer records were sufficiently complete with regard to diagnoses (82% of all items recorded), prescriptions (100%) and referrals (67%), but missed most of the remaining data that a manual record captured. The videorecorded validation study showed that there were no important lapses in the recording of diagnoses, prescriptions or referrals when the computer recording was compared to the actual process of the consultations. CONCLUSION: In these four high-recording practices the data in computer records were of sufficient completeness and accuracy to allow meaningful data aggregation for some diagnoses, prescriptions and referrals. Standardized protocols for defining which patients are included and excluded from major disease groups are required.

England↗

PubMedDate not supplied

[Use of high doses of aprotinin in cardiac surgery].

OBJECTIVES: To study the efficacy of aprotinin in reducing whole blood loss after cardiac surgery with extracorporeal circulation. PATIENTS AND METHODS: Two groups of patients undergoing cardiac surgery with extracorporeal circulation were studied. Group I (n = 51) received 2 x 10(6) KIU (kallikrein inhibiting units) of aprotinin upon anesthetic induction, a similar dose in the extracorporeal circulation priming pump, and a maintenance dose of 500,000 KIU/h until removal from the operating theater. Group II (n = 51) was the control group. Patients that had previously undergone surgery with extracorporeal circulation were excluded, as were those being treated with anti-coagulants or anti-aggregants. Data recorded were blood volume, transfusions needed in the first 24 h, and blood derivatives used throughout the hospital stay. Postoperative kidney function was also determined. The occurrence of acute myocardial infarction in patients undergoing myocardial revascularization was also noted. RESULTS: Group I required a mean of 2.40 U of concentrated red blood per patient during the first postoperative day, as opposed to a mean of 4.3 U in group II (p < 0.001). Blood loss through drains was also less in group I than in group II (431.82 vs 895.29 ml; p < 0.001). Total blood needed during the hospital stay was 3.50 units per patient in group I vs 5.40 U in group II (p < 0.001). Urea and creatinine were similar in the two groups before and after surgery (p = NS), and there were no significant differences in the number of cases of acute myocardial infarction in the two groups (3 in group I and 2 in group II). CONCLUSIONS: Administration of high doses of aprotinin is an effective technique for reducing the need for whole blood in patients requiring extracorporeal circulation during surgery. The technique does not compromise kidney function or increase the risk of perioperative acute myocardial infarction.

Adult↗

PubMed1995

An epidemiologist's viewpoint on screening.

Prostate cancer is an important disease causing a considerable number of new cases, deaths and premature loss of life each year. Three screening tests have been suggested: DRE, TRUS and PSA measurement in venous blood. From aggregated data from studies examining the performance of these tests, DRE or PSA measurement look the most promising with respect to their estimated detection rates and false positive rates (detection rate [DR] = 68%, false positive rate [FPR] = 5% for DRE and DR = 79%, FPR = 8% for PSA with a cut off of > 4 micrograms/l). However, these results are tentative-more research is needed on the performance of these screening tests. In particular, the prevalence of prostate cancer in the studies was considerably higher than that expected in the general population and so the OAPR estimates derived are more favourable than predicted. A randomized controlled trial of prostate cancer screening is needed to know whether screening reduces mortality from this disease, although this would take about 10 years to perform. Current stage distribution and 5 year survival data suggest that if screening could increase the proportion of cancers diagnosed at the localized clinically inapparent stage from 23% (currently diagnosed) to 100%, this would represent an equivalent reduction in mortality of 48%-about 1500 lives saved per year if screening were offered to 55-74 year old men. When more substantive information is available on the potential screening tests, it may be appropriate to conduct a randomized controlled trial. In the meantime, any ad hoc screening should be strongly discouraged.

Humans↗

PubMed1993

[Hemodilution therapy in patients with acute anterior ischemic optic neuropathy].

A prospective study was performed in 22 patients with an anterior ischaemic optic neuropathy (AION). All patients underwent iso- (Hct > or = 42%) or hypervolemic (Hct < 42%) haemodilution for 10 days with daily infusion of 250 ml hydroxyethyl starch (MW 200,000/0.5, 10% HAES-sterile) in combination with pentoxifylline (p.o.: 1200 mg/day; i.v.: 300 mg/day; Trental). Only patients with recent AION (less than 2 weeks' duration of symptoms) were considered for the prospective trial. Clinical, haemodynamic (arterio-venous passage time) and rheological (haematocrit, plasma viscosity, erythrocyte aggregation) data of all patients were recorded before therapy and after 10 days. An improvement of central vision by 2 or more lines was seen in 7 patients after 10 days. Initially the arterio-venous passage time was significantly prolonged in patients (2.42 +/- 0.7 s) with AION compared with healthy volunteers (1.45 +/- 0.4 s). After the 10-day trial arterio-venous passage time was significantly shorter than baseline values. In addition, the initially elevated plasma viscosity (1.33 +/- 0.1 mPa) was significantly lowered by haemodilution therapy.

Aged↗

PubMed1994

Interrater reliability of the 7-level functional independence measure (FIM)

The Functional Independence Measure (FIM) is an 18-item, 7-level scale developed to uniformly assess severity of patient disability and medical rehabilitation functional outcome. FIM interrater reliability in the clinical setting is reported here. Clinicians from 89 US inpatient comprehensive medical rehabilitation facilities newly subscribing to the uniform Data System for Medical Rehabilitation from January 1988-June 1990 evaluated 1018 patients with the FIM. FIM total, domain and subscale score intraclass correlation coefficients (ICC) were calculated using ANOVA; FIM item score agreement was assessed with unweighted Kappa coefficient. Total FIM ICC was 0.96; motor domain 0.96 and cognitive domain 0.91; subscale score range: 0.89 (social cognition) to 0.94 (self-care). FIM item Kappa range: 0.53 (memory) to 0.66 (stair climbing). A subset of 24 facilities meeting UDSMR data aggregation reliability criteria had Intraclass and Kappa coefficients exceeding those for all facilities. It is concluded that the 7-level FIM is reliable when used by trained/tested inpatient medical rehabilitation clinicians.

Activities of Daily Living↗

PubMed1995

Health insurance coverage and receipt of preventive health services--United States, 1993.

In 1992, an estimated 38.5 million U.S. residents aged < 65 years did not have health insurance (1). Efforts by states to expand health-care coverage will require surveillance for and state-specific information about coverage for acute care and the receipt of preventive services. This report summarizes state-specific and aggregated data from the 1993 Behavioral Risk Factor Surveillance System (BRFSS) regarding the status of health insurance coverage and the receipt of preventive health services among adults aged 18-64 years. In addition, findings from the analysis of supplemental questions added to the BRFSS in Minnesota are included that address health-care utilization, source of health-care coverage, and coverage of children.

Adult↗

PubMed1994

Sulfasalazine and mesalazine for the maintenance therapy of Crohn's disease: a meta-analysis.

OBJECTIVE: The aim of this meta-analysis was to determine whether therapy with sulfasalazine or mesalazine is effective in the maintenance of clinical remission in patients with Crohn's disease. METHODS: Computerized searches of bibliographic databases were carried out to identify studies published up to October 1993 that were randomized controlled trials of sulfasalazine or mesalazine as single drug therapy in the prevention of symptomatic disease relapse in quiescent Crohn's disease. We extracted and statistically aggregated data from the trials, using a fixed effects model. RESULTS: A total of 10 eligible trials involving a total of 1022 patients were identified. Therapy with sulfasalazine or mesalazine reduces the risk of clinical relapse of Crohn's disease after 12 months [relative risk (RR) = 0.77, 95% confidence interval (CI) 0.64-0.92]. The benefit is less apparent at 3-6 months [RR = 0.86, 95% CI 0.67-1.09]. Subgroup analysis indicated that therapeutic benefit exists for mesalazine but not for sulfasalazine [RR for mesalazine = 0.63, 95% CI 0.50-0.79; RR for sulfasalazine = 1.08, 95% CI 0.81-1.44]. CONCLUSIONS: Maintenance therapy with mesalazine or sulfasalazine reduces the risk of clinical disease relapse in Crohn's disease after 1 yr. This benefit is seen primarily in the more recent studies that have used mesalazine as the therapeutic agent.

Aminosalicylic Acids↗

PubMed1994

State-specific trends among women who did not receive prenatal care--United States, 1980-1992.

Lack of prenatal care is strongly associated with an increased risk for low birthweight (< 2500 g [< 5 lbs 8 oz] at birth) infants, preterm delivery, and maternal and infant mortality (1). From 1980 through 1992, the nationally aggregated percentage of pregnant women who did not receive prenatal care increased by 31%--from 1.3% to 1.7% (2,3). Because nationally aggregated data can obscure variations among states, CDC analyzed state-specific data derived from birth certificates for 1980-1992 to examine trends among women who did not receive prenatal care. This report summarizes the findings of the analysis.

Female↗

PubMed1994

Violent crime: the role of alcohol and new approaches to the prevention of injury.

Almost all evidence of a link between alcohol consumption and violence is available only in the form of aggregate data. This is unsatisfactory and case-control investigations and studies which relate injury severity to blood alcohol levels are needed. In the few closely controlled studies which have been performed, increased risk of injury in assault has been linked with binge consumption of more than about 8 units, and above average weekly consumption only in those over 25 years. Raising the minimum purchasing age for alcohol to 21 years, learning to drink responsibly with parents, especially fathers, and the adoption of tempered glassware are all achievable objectives which would reduce alcohol-related injury. The use of sobriety-checkpoints (breath testing though not by the police) and other situational prevention programmes need to be evaluated in relation to reducing injury sustained in violent crime. Proactive, community policing has been shown to reduce levels of alcohol-related violent crime, in contrast to more reactive, defensive and confrontational policing. The concept of 'capable guardianship' to establish and maintain social control of young delinquents needs to be extended, particularly near known foci of violence such as bars and adjacent fast-food outlets and taxi-ranks.

Alcohol Drinking↗

PubMed1994

Repeat cesareans: how many are elective?

OBJECTIVE: To describe the clinical indications for repeat cesarean delivery and to compare these with indications for primary procedures. METHODS: We reviewed cesarean deliveries at our academic nonprofit hospital during 1992 (n = 1885). The indication for the procedure was abstracted based on surgeon operative reports and discharge ICD-9 codes (International Classification of Diseases, Clinical Modification, 9th Edition). RESULTS: The hospital cesarean rate was 28.7%; 34% of these were repeat procedures (n = 643). Elective cesarean delivery was the leading cause of repeat cesareans, followed by "other" indications, dystocia, breech, and fetal distress. In contrast, dystocia was the leading cause for primary cesarean, followed by fetal distress, "other," and breech presentation. One hundred women (15.6%) undergoing repeat cesarean had absolute or relative contraindications to a trial of labor. CONCLUSIONS: Indications for cesareans using hierarchies based on ICD-9 codes do not attempt to differentiate categories of indications for repeat cesarean. Current recommendations for lowering cesarean rates by increasing vaginal birth after previous cesarean are based on aggregate data and do not recognize that some repeat cesareans are clinically indicated. A coding system designed to distinguish elective from indicated repeat cesareans would be useful for future prospective studies.

Adult↗

PubMed1994

[Back pain syndromes in dentists. Diagnosis and differential diagnosis].

The literature evaluating the occurrence of back pain syndrome in dentists was reviewed. The data aggregated provide an evidence that cervical and lumbosacral pains are the most common complains as far as the locomotor system is concerned. Principles of diagnosis and identification of symptoms among other diseases were discussed.

Adult↗

PubMed1994

The rates of G:C-->T:A and G:C-->C:G transversions at CpG dinucleotides in the human factor IX gene.

We have identified eight independent transversions at CpG in 290 consecutive families with hemophilia B. These eight transversions account for 16.3% of all independent transversions in our sample, yet the expected frequency of CpG transversions at random in the factor IX gene is only 2.6% (P < .01). The aggregate data suggest that the two types of CpG transversions (G:C-->T:A and G:C-->C:G) possess similar mutation rates (24.8 x 10(-10) and 20.6 x 10(-10), respectively), which are about fivefold greater than the comparable rates for transversions at non-CpG dinucleotides. The enhancement of transversions at CpG suggests that the model by which mutations occur at CpG may need to be reevaluated. The relationship, if any, between deamination of 5-methyl cytosine and enhancement of transversions at CpG remains to be defined.

Amino Acid Sequence↗