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PubMed1998

Combining laboratory data sets from multiple institutions using the logical observation identifier names and codes (LOINC).

A standard set of names and codes for laboratory test results is critical for any endeavor requiring automated data pooling, including multi-institutional research and cross-facility patient care. This need has led to the development of the logical observation identifier names and codes (LOINC) database and its test-naming convention. This study is an expansion of a pilot study using LOINC to exchange laboratory data between Columbia University Medical Center in New York and Barnes Hospital at Washington University in St. Louis, where we described complexities and ambiguities that arose in the LOINC coding process (D.M. Baorto, J.J. Cimino, C.A. Parvin, M.G. Kahn, Proc. Am. Med. Inf. Assoc. 1997). For the present study, we required the same two medical centers to again extract raw laboratory data from their local information system for a defined patient population, translate tests into LOINC and provide aggregate data which could then be used to compare laboratory utilization. Here we examine a larger number of tests from each site which have been recoded using an updated version of the LOINC database. We conclude that the coding of local tests into LOINC can often be complex, especially the 'Kind of Property' field and apparently trivial differences in choices made by individual institutions can result in nonmatches in electronically pooled data. In the present study, 75% of failures to match the same tests between different institutions using LOINC codes were due to differences in local coding choices. LOINC has the potential to eliminate the need for detailed human inspection during the pooling of laboratory data from diverse sites and perhaps even a built-in capability to adjust matching stringency by selecting subsets of LOINC fields required to match. However, a quality standard coding procedure is required and examples highlighted in this paper may require special attention while mapping to LOINC.

Clinical Laboratory Techniques↗

PubMed2005

Scaling of the kinetics of slow aggregation and gel formation for a fluorinated polymer colloid.

The aggregation and gelation kinetics in moderately concentrated (0.004 </= phi(0) </= 0.1) colloidal dispersions of fluorinated polymer particles has been studied. The aggregation was adjusted to proceed slowly enough to allow a convenient characterization of the kinetics through static and dynamic light scattering on quenched and diluted samples. A population balance model based on second-order aggregation rates is developed to compute the time evolution of the cluster mass distribution, from which we calculate the values of the average radii and structure factor measured by light scattering, so as to allow a direct comparison between measured and calculated quantities. The model suggests the introduction of a dimensionless time which allows the scaling of all the aggregation data on unique master curves defined by only two parameters: the exponent of the power-law aggregation kernel, lambda, and the aggregate fractal dimension, d(f). The predicted master curves were observed experimentally, which confirms the validity of the aggregation model and allows the unique determination of the kinetic and structural parameters of the aggregation process. The cluster growth behavior, although significantly slower than DLCA, shows power-law kinetics rather than the exponential one typical of RLCA and the cluster structure is characterized by an unexpectedly small fractal dimension, d(f) = 1.7. The occurrence of gelation has been characterized using small amplitude oscillatory shearing to monitor the time evolution of the elastic modulus. It is found that also these curves, together with the gel time value, scale with the stability ratio of primary particles for a given solid volume fraction. We further use the model to calculate the cumulative occupied volume fraction of the growing aggregates and quantify in this way the increasing space filling, which is solid volume fraction dependent. The experimentally determined dimensionless gel times, which are also solid volume fraction dependent, scale then directly with the dimensionless time to reach a certain degree of the space filling in the model. This finding suggests that, like the aggregation kinetics, the gelation kinetics is governed by a second-order rate process.

Journal Article↗

PubMed1997

Using Logical Observation Identifier Names and Codes (LOINC) to exchange laboratory data among three academic hospitals.

Using a standard set of names and codes to exchange electronic laboratory data would facilitate multiinstitutional research and data pooling. This need has led to the development of the Logical Observation Identifier Names and Codes (LOINC) database and its test naming convention. We conducted a study which required 3 academic hospitals (in 2 separate medical centers) to extract raw laboratory data from their local information system for a defined patient population, translate tests into LOINC, and provide aggregate data which could then be used to compare laboratory utilization. We found that the coding of local tests into LOINC can often be complex, especially the "Kind of Property" field, and apparently trivial differences in choices made by individual institutions can result in nonmatches in electronically pooled data. In our study, 72-86% of the failures of LOINC to match the same tests between different institutions were due to differences in local coding choices. LOINC has tremendous potential to eliminate the needing for detailed human inspection during the pooling of laboratory data from diverse sites, and perhaps even a built-in capability to adjust matching stringency by selecting subsets of LOINC fields required to match. However, a quality, standard coding procedure at all sites is critical.

Academic Medical Centers↗

PubMed1977

Levels of reliability in fertility survey data.

A number of factual and attitudinal questions asked in the 1973 Taiwan KAP-4 survey were repeated in a postenumeration survey one month later in order to assess the reliability of responses of the 286 women reinterviewed. The level of reliability is found to vary depending on the measures used and on whether the focus is aggregate data or individual responses. Analysis of consistency of responses shows that while overall reliability at both aggregate and individual levels is reasonably good, there is greater reliability for factual than for attitudinal data. Nevertheless, consistency of responses on factual questions varies considerably depending on the salience of the topic to the respondent. Estimates of reliability are shown to depend on the measure used and on the skewness of the distributions of the responses.

Contraception↗

PubMed2005

Paper and voice MAYSI-2: format comparability and concordance with the voice DISC-IV.

The authors examine the comparability of paper and voice formats of the Massachusetts Youth Screening Instrument-Second Version (MAYSI-2) as well as each format's concordance with the Voice Diagnostic Interview Schedule for Children (DISC) among adjudicated youth. Comparability is assessed among 248 youths admitted to a South Carolina Assessment Center. Mean scores and alpha coefficients are calculated, and area under the curve and positive and negative predictive values are used to compare concordance to the DISC. Paper and voice formats are significantly correlated, have similar alpha coefficients, and have comparable concordance with the DISC, suggesting that the MAYSI-2 paper and voice formats are comparable instruments. The voice format may be preferable to the paper format for screening justice youth for mental health problems because it may reduce incomplete data and increase reporting of stigmatized behaviors and because of its ability to automatically generate scored reports and aggregate data.

Adolescent↗

PubMed2006

Further clarification of the contribution of the tryptophan hydroxylase (TPH) gene to suicidal behavior using systematic allelic and genotypic meta-analyses.

Suicide is a major public health issue, especially in western countries, accounting for approximately 1 million deaths every year throughout the world. The tryptophan hydroxylase (TPH) gene has been extensively studied as a candidate for suicidal behavior due to its role in serotonergic neurotransmission. Since the first study associating the gene with schizophrenia, there have been many attempts to replicate it. However, a number of these studies have produced contrary results, possibly reflecting inadequate statistical power and the use of different populations. Association data relating European and, more particularly, Asian populations has become increasingly available in recent years. To examine whether the aggregate data provide evidence of statistical significance, the current meta-analysis has combined all the published studies up to July 2005, and examined the polymorphisms (A779C, A218C, A-6526G) in the context of varied suicidal behaviors by analyzing the studies in total and in subsets. Compared with the inconsistent results of previous studies, the current results (22 references) confirm a strong overall association between suicidal behavior and the A779C/A218C polymorphisms, supporting the involvement of TPH in the pathogenesis of suicidal behavior.

Gene Frequency↗

PubMed2005

Current status of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons Congenital Heart Surgery Database.

BACKGROUND: After utilizing separate congenital databases in the early 1990s, the Society of Thoracic Surgeons (STS) and the European Association for Cardio-Thoracic Surgery (EACTS) collaborated on several joint database initiatives. METHODS: In 1998, the joint EACTS-STS International Congenital Heart Surgery Nomenclature and Database Project Committee was created and a common nomenclature and common core minimum database dataset were adopted and published by the STS and the EACTS. In 1999, the joint EACTS-STS Aristotle Committee was created and the Aristotle Score was adopted and published as a method to provide complexity adjustment for congenital heart surgery. Collaborative efforts involving the EACTS and STS are underway to develop mechanisms to verify data completeness and accuracy. RESULTS: Since 1998, this nomenclature, database, and methodology of complexity adjustment have been used by both the STS and EACTS to analyze outcomes of over 40,000 patients. A huge amount of data have been generated which allow comparison of practice patterns and outcomes analysis between Europe and North America. The aggregate data from the first 5 years of data collection not only make for interesting comparison but also allow examination of regional difference in practice patterns. For example, in the EACTS, out of 4,273 neonates, 885 (20.7%) underwent arterial switch procedures and 297 (6.95%) underwent Norwood stage 1 procedures. In the STS, out of 3,988 neonates, 472 (11.8%) underwent arterial switch procedures and 575 (14.4%) underwent Norwood stage 1 procedures. CONCLUSIONS: This analysis of the EACTS-STS multi-institutional outcomes database confirms that in both Europe and North America, case complexity and mortality is highest among neonates, then infants, and then children. Regional differences in practice patterns are demonstrated, with the overall goal being the continued upgrade in the quality of surgery for congenital heart disease worldwide.

Databases, Factual↗

PubMedDate not supplied

The association between sulfate air pollution and mortality at the county scale: an exploration of the impact of scale on a long-term exposure study.

The American Cancer Society (ACS) Study and its reanalysis are built upon in order to examine the impact of scale on the observed relationship between sulfates and mortality. The limitations of the original ACS Study (Pope et al., 1995) and the reanalysis of this study (Krewski et al., 2000) are discussed; while the latter dealt with some issues in using ecological data, it did not address scale. Next, the article outlines the county-scale study, the methods used to aggregate data, and the two-stage analysis used to derive relative risk (RR). Finally, the results of working at the county scale are compared with those obtained by the reanalysis team using larger metropolitan areas. Less than half of the cohort used in the metropolitan study were used at the county scale because of the limited availability of sulfate monitors and because five-digit ZIP codes more accurately assigned individuals to geographical areas. Therefore, the county data should be considered as new and not as a reorganization of the original data set. The reanalysis and the county studies should be considered as two separate studies that took different scales as their basic organizing principle. The RR of all-cause mortality from sulfate exposure at the county scale was 1.50 (1.30, 1.73) compared with 1.25 (1.13, 1.37) at the metropolitan scale; for cardiopulmonary mortality, the RR was 1.75 (1.48, 2.08) at the county scale compared with 1.29 (1.15, 1.46) at the metropolitan scale. Because lung cancer mortality was low in some counties, the two-stage random effects model became unstable. At the county scale, the RR from sulfates was more robust to the inclusion of ecologic covariates. Other place-specific ecologic covariates were either insignificant or barely significant (with a lower 95% confidence limit near 0.99 or 1.00) when included in the two-stage regression model for all-cause mortality with sulfates. Moreover, no ecologic covariate changed the RR of all-cause mortality from sulfates by 25% or more. Both population change and unemployment rate affected the RR for cardiopulmonary mortality from sulfate exposure by 25% or more in the county-scale analysis. However, when these two variables were entered into a multiple covariate analysis, the RR from sulfates decreased but remained strongly significant. Sulfur dioxide was not an important covariate at the county scale. Thus, at the county scale, long-term exposure to sulfates appears to be more strongly associated with increased risk of all-cause and cardiopulmonary mortality than previously indicated by the ACS study and its reanalysis.

Air Pollution↗

PubMed2000

Effect of filmless imaging on the utilization of radiologic services.

PURPOSE: To determine the effect of a large-scale picture archiving and communication system (PACS) on in- and outpatient utilization of radiologic services. MATERIALS AND METHODS: Data were collected at the Baltimore Veterans Affairs (VA) Medical Center (BVAMC) before and after implementation of an enterprise-wide PACS; the numbers and types of imaging examinations performed for fiscal years 1993 and 1996 were evaluated. These data were compared with those from a similar academic medical center, the Philadelphia VA Medical Center (PVAMC), and with aggregate data obtained nationally for all VA hospitals over comparable periods. RESULTS: Inpatient utilization, defined as the number of examinations per inpatient day, increased by 82% (from 0.265 to 0.483 examinations per patient day) after a transition to filmless operation at BVAMC. This is substantially greater than the increases of 38% (from 0.263 to 0.362 examinations per patient day) and 11% (from 0.190 to 0.211 examinations per patient day) at the film-based PVAMC and nationally, respectively. Outpatient utilization, defined as the number of examinations per visit, increased by 21% (from 0.108 to 0.131 examinations per visit) at BVAMC, compared with a 1% increase (from 0.087 to 0.088 examinations per visit) at PVAMC and a net decrease of 19% (from 0. 148 to 0.120 examinations per visit) nationally. CONCLUSION: The transition to filmless operation was associated with increases in inpatient and outpatient utilization of radiologic services, which substantially exceeded changes at PVAMC and nationally over the same interval.

Academic Medical Centers↗

PubMed2000

New insights into extended prophylaxis after orthopaedic surgery - the North American Fragmin Trial experience.

It is well-known that peri-operative and post-operative venous thrombosis are common. Trials in Europe have shown that extended out-of-hospital prophylaxis with a low-molecular-weight heparin reduces the rate of deep vein thrombosis in patients undergoing elective hip surgery. North American investigators of limited-outcome descriptive studies, however, have suggested that out-of-hospital prophylaxis is not necessary. To resolve this uncertainty, NAFT (North American Fragmin Trial) was conducted, the results of which are summarized in this paper. The findings of NAFT support the favourable findings of the European studies on extended prophylaxis. Furthermore, European data have shown extended out-of-hospital prophylaxis to be cost-effective. On the basis of the aggregate data, it is felt that the A2 recommendation made by the Fifth American College of Chest Physicians consensus conference for extended prophylaxis should be changed to an A1 recommendation.

Anticoagulants↗

PubMed2001

Health inequality in Slovenia.

The aim of this study was to correlate some socio-economic factors (gender, income, education, social position) with some health indicators (life expectancy, death rate by selected causes of death, self-evaluation of one's own health, absence from work due to illness or injuries) with a purpose to define the ineqaulity in health across Slovenian municipalities. In our study two sources of data for the population of Slovenia in 1996 were used: from the Statistical Office of the Republic of Slovenia (aggregated data across Slovenian municipalities) and Public Opinion Research (individual data). Statistical analysis was performed by correlation and factor analysis. The correlation coefficient between education and life expectancy is 0.712. The correlation between income base and life expectancy is also significant (0.707). In the eastern part of the country (mostly rural population) women in average live 2 years and men 3 years less than their counterparts in the western part of the country. Five causes of death across Slovenian municipalities are significantly related to the population's education and incomes, of which only death due to neoplasm is positively correlated to income while all other causes are negatively correlated not only with income but also with education. Health (self-evaluation) is closely related to an individual's education and social position. The factor analysis of pressures at work showed groups of two factors as being the most significant: pressures related to leadership positions (positive correlation with health), and physical labour or work in inferior positions (negative correlation with health). We can conclude that the results of our study showed the crucial effect of investigated socio-economic factors on people's health across Slovenian municipalities. During the present socio-economic transition period we are trying to establish new sources of data and looking for possibilities to connect and refine them for further investigation.

Health Status↗

PubMed2005

The Community Physicians' Network (CPN): an academic-community partnership to eliminate healthcare disparities.

INTRODUCTION: Disparities in health care are maintained by three primary factors: 1) patient factors which include multiple risk factors and comorbidities; 2) healthcare practitioner factors comprising inconsistent application of practice guidelines due to a limited database of clinical trials of effective therapies in African Americans and other underrepresented minorities; and 3) barriers in the healthcare delivery system resulting in poor access to care. The Morehouse School of Medicine Community Physicians' Network (CPN) was established to address disparities in health care by focusing on provider-specific strategies. OBJECTIVES: To: 1) use disease-specific registries to identify treatment gaps and facilitate quality improvement processes among CPN practices; 2) develop practice-specific and guideline-based educational messages to promote quality care; 3) engage and train CPN-physicians for participation in approved NIH, other government, and industry-supported clinical protocols; and 4) develop a data repository of all CPN-sponsored clinical trials that include significant numbers of African Americans and other underrepresented minorities. METHODS: The disease-specific outpatient registries will have the following features: 1) data structures and data elements will use standard database codes and a data dictionary; 2) HIPPA-compliant data abstraction and data transfer tool; 3) baseline chart review to establish practice patterns and provide practice-specific feedback; 4) annual update of registry; 5) data registry and repository maintained on Morehouse School of Medicine's secure servers; 6) registry publications will include only aggregate data, without identification of contributing practices; 7) an electronic medical records platform will be encouraged as the ultimate data management tool for CPN practices. In addition, up to three continuing medical education (CME) programs each year will feature national speakers and promote evidence-based practice guidelines. RESULTS: Eighty-five primary care and subspecialty practices are actively enrolled in CPN with a total of 385,000 annual outpatient visits. The makeup of insurance status is: HMO/PPO (45%); Medicare only (19%); Medicare HMO (11%); Medicare plus (8%); Medicaid (6%); Uninsured (11%). CONCLUSIONS: The Community Physicians' Network will address specific gaps in the health care of African-American and other minority patients by promoting quality care among its members and by facilitating participation in approved clinical trial protocols. The unique academic community partnership is consistent with the NIH roadmap goal of eliminating healthcare disparities.

Black or African American↗

PubMed1997

Association between ambient air concentrations of nitrogen dioxide and respiratory symptoms in children in Prague, Czech Republic. Preliminary results from the Czech part of the SAVIAH Study. Small Area Variation in Air Pollution and Health.

The primary objective of the SAVIAH, a multi-centre study funded by European Union, was to assess new methodology for study of small area health statistics and to implement it in epidemiological health statistics and geography. In Prague, the study has been conducted in two city districts with large variation in air pollution. Data at individual level (health symptoms and socio-economic circumstances of the family) were collected by questionnaires completed by parents of 3680 children aged 7-10 both resident and attending schools within the area (response rate 88%). Aggregated data for geographical areas were available from census and urban planning sources for 692 enumeration districts in the study area which were aggregated into 75 medium sized areas. Outdoor concentrations of nitrogen dioxide (NO2) were monitored by passive samplers. All these data were integrated into a geographic information system (GIS). Spatial distribution of air pollution was estimated by kriging and multiple regression modelling. These models explained about 80% of the variation in air pollution measured by passive samplers. GIS was then used to assign to individuals an exposure based on place of residence and school in order to conduct individual based analyses. Association between NO2 and life-time prevalence of wheezing and/or whistling, and wheezing/whistling in the last 12 months was studied by logistic regression. For both outcomes, school levels of NO2 were positively related to symptoms but home levels of NO2 showed a negative association. Logistic regression at individual level gives similar results as ecological analysis and multilevel modelling. Hierarchical model yielded somewhat wider confidence limits. Adjustment for parental behavioural and socio-economic factors did not affect these estimates substantially. This study demonstrated the power of the GIS methodology in studying the effects of complex environmental factors on respiratory health of children.

Air Pollution↗

PubMedDate not supplied

1994 task analysis of American certified nurse-midwifery.

The ACNM Certification Council is responsible to the American College of Nurse-Midwives for the development, administration, and evaluation of a psychometrically sound and legally defensible certification examination in nurse-midwifery. A task analysis study was conducted to investigate the knowledge, skills, and abilities that define American nurse-midwifery practice. A stratified sample of 825 American College of Nurse-Midwives members was asked to rate the frequency of performance and the criticality of 189 nurse-midwifery activities and 109 discrete diagnoses that the nurse-midwife might encounter while providing clinical care. The frequency and critically ratings were combined to generate an importance weight for each activity. Study data will be used as the basis of the examination blueprint in order to ensure job-related content validity. Aggregate data can also be used for curriculum development, self-assessment, and evaluation research purposes.

Adult↗

PubMed2005

National Breast Cancer Audit: establishing a web-based data system.

BACKGROUND: An audit of surgical treatment of early breast cancer was introduced nationally in 1999. In August 2002, the Australian Safety and Efficacy Register of New Interventional Procedures - Surgical, under the auspices of the Royal Australasian College of Surgeons, assumed responsibility for managing this audit. This article provides an update of audit activities, now known formally as the National Breast Cancer Audit (NBCA), including a description of the new governance structure and the development of a secure online surgical audit system. METHODS: Major changes have taken place in the design and governance of the NBCA during the last two years. Two committees have been established to oversee the audit. A clinical advisory committee comprises experts from a number of fields including breast surgery, oncology, government, and from peak breast cancer and consumer bodies. A technical advisory committee oversees many of the technical issues that have arisen with the development of an online data entry system. The online system of data entry was developed and launched to surgeons in May 2004. RESULTS: There are now 28,000 cases of primary breast surgery in the audit. Around 250 surgeons are currently participating, an increase of over 50 surgeons since May 2004. Surgeons can review their data using the online system and compare their own results by generating reports which graph their own results against national aggregate data. CONCLUSIONS: There has been a significant increase in the volume of data received since the launch of the secure online system. The governing committees are working towards creating a clinical audit which will provide an improved data entry system and better reporting for all participating surgeons. The NBCA can also serve as a template on which to base other surgical audits.

Adolescent↗

PubMed1985

Marital state, alcohol consumption, and liability to myocardial infarction, stroke, diabetes mellitus, or hypertension in men from Gothenburg.

Data from the Swedish personal number system were used to examine rates of admissions to hospital, particularly with myocardial infarction, stroke, diabetes mellitus, or hypertension, in relation to marital state and histories of admission with alcoholism in 77843 men from Gothenburg born in 1911-40. The number of admissions to hospital with the four diseases varied with marital state and history of admission with alcoholism, but by considering each subset from the total group it was possible to show that among alcoholic men no material variation in the number of admissions was evident. By contrast, among the non-alcoholic men those who were married were particularly prone to myocardial infarction but less likely to be admitted with stroke or diabetes mellitus than the unmarried or divorced men. The data show the value of common personal and health statistical numbering systems in generating epidemiological information beyond that obtainable from aggregated data without a record linkage technique.

Alcoholism↗

PubMedDate not supplied

From minimum data to maximum impact: using clinical data to strengthen patient care.

Society mandates that health care be both effective and affordable. Currently, data about costs of care are more readily obtainable than data about quality, especially in relation to nursing and other nonphysician aspects of patient care. Assessing effectiveness of care requires standardized data aggregated in databases for comparisons across times, conditions, and institutions. Historical and contemporary efforts to identify elements of a minimum data set and develop standards have brought progress but have not resolved all the critical issues. A project involving the University Hospital Consortium and its member institutions has produced a valid and reliable set of standard terms and codes compatible with an existing patient-level database. Future developments need to include better methods for determining resource consumption and for capturing clinical data. The time is near when databases built from clinical data will lead to knowledge that will strengthen patient care.

Data Collection↗

PubMed1996

From minimum data to maximum impact: using clinical data to strengthen patient care.

Databases, Factual↗