Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Indication”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources
PubMed2005

General practitioners prefer prescribing indicators based on detailed information on individual patients: a Delphi study.

OBJECTIVE: To assess the face validity of both simple and advanced quality indicators for prescribing in general practice. METHODS: In a three-round Delphi study, 100 randomly selected general practitioners (GPs) in Denmark rated 18 indicators for prescribing of non-steroidal anti-inflammatory drugs. All indicators were based on prescription register data and focused on different prescribing aspects. Advanced indicators contained information at the patient level, viz. age, sex and history of drug use, while simple indicators only used drug statistics at practice level. Indicators were rated on a nine-point Likert scale. Consensus among GPs was defined as interquartile ranges of three or less. A median rating of 7-9 was interpreted as face validity and a median rating of 1-3 as no face validity. RESULTS: Participation in the study was accepted by 44 GPs and 37 completed all three rounds. Three indicators based on patient level data and focusing on adverse effects were assessed to have face value. One indicator focusing on costs and based on practice level data was considered unsuitable for evaluating the quality of prescribing. Consensus was not reached for the remaining indicators. CONCLUSIONS: GPs do not regard simple indicators based on aggregated data at practice level as suitable for evaluating the prescribing quality in general practice, but prefer indicators that rest on clinical data at the patient level.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

Operational indicators for measuring agricultural sustainability in developing countries.

This paper reviews relevant literature on the sustainability indicators theoretically proposed and practically applied by scholars over the past 15 years. Although progress is being made in the development and critical analysis of sustainability indicators, in many cases existing or proposed indicators are not the most sensitive or useful measures in developing countries. Indicator selection needs to meet the following criteria: relative availability of data representing the indicators, sensitivity to stresses on the system, existence of threshold values and guidelines, predictivity, integratability and known response to disturbances, anthropogenic stresses, and changes over time. Based on these criteria, this paper proposes a set of operational indicators for measuring agricultural sustainability in developing countries. These indicators include ecological indicators involving amounts of fertilizers and pesticides used, irrigation water used, soil nutrient content, depth to the groundwater table, water use efficiency, quality of groundwater for irrigation, and nitrate content of both groundwater and crops. Economic indicators include crop productivity, net farm income, benefit-cost ratio of production, and per capita food grain production. Social indicators encompass food self-sufficiency, equality in food and income distribution among farmers, access to resources and support services, and farmers' knowledge and awareness of resource conservation. This article suggests that the selection of indicators representing each aspect of sustainability should be prioritized according to spatial and temporal characteristics under consideration.

Agriculture↗
PubMed2004

Indices of nonlinearity in finger force interaction.

Experiments with force production by subsets of fingers within the human hand have shown that finger interaction may be significantly nonlinear. In particular, this nonlinearity is reflected in the phenomenon of force deficit, a drop of the peak force of a finger when several fingers act simultaneously. We describe nonlinear effects in force relations within finger pairs, triplets, etc. Finger forces are represented as the sums of components resulting from force interactions within all subsets of the explicitly involved (master) fingers. The values of these components computed at extreme values of control signals, zero and unity, are taken as indices of such "elementary" force interactions. Indices of the first order reflect purposeful force production by a single master finger and its effects on forces produced by other fingers (enslaving). Indices of the second order reflect additional influences from pairs of simultaneously recruited master fingers, etc. Force interaction indices were computed based on finger forces measured in earlier experiments. Signs of indices alternated with their order, being positive for the indices of the first order (enslaving), negative for the indices of the second order (force deficit), positive for the indices of the third order, and mostly negative for the indices of the fourth order. Indices of the third and fourth orders reflect phenomena of force interaction not reported earlier. The study emphasizes the importance of nonlinear interactions among finger forces and introduces a set of independent indices that can be used to quantify such interactions in different subpopulations and their possible changes with practice and/or rehabilitation of the hand function.

Fingers↗
PubMed2005

Consumer health information on the Internet about carpal tunnel syndrome: indicators of accuracy.

PURPOSE: To identify indicators of accuracy for consumer health information on the Internet. METHODS: Several popular search engines were used to find websites on carpal tunnel syndrome. The accuracy and completeness of these sites were determined by orthopedic surgeons. It also was noted whether proposed indicators of accuracy were present. The correlation between proposed indicators of accuracy and the actual accuracy of the sites was calculated. RESULTS: A total of 116 websites and 29 candidate indicators were examined. A high Google toolbar rating of the main page of a site, many inlinks to the main page of a site, and an unbiased presentation of information on carpal tunnel syndrome were considered genuine indicators of accuracy. Many proposed indicators taken from published guidelines did not indicate accuracy (e.g., the author or sponsor having medical credentials). CONCLUSION: There are genuine indicators of the accuracy of health information on the Internet. Determining these indicators, and informing providers and consumers of health information about them, would be useful for public health care. Published guidelines have proposed many indicators that are obvious to unaided observation by the consumer. However, indicators that make use of the invisible link structure of the Internet are more reliable guides to accurate information on carpal tunnel syndrome.

Carpal Tunnel Syndrome↗
PubMed1993

Relating outcomes to processes of care: the Maryland Hospital Association's Quality Indicator Project (QI Project).

BACKGROUND: The Maryland Hospital Association's Quality Indicator Project (QI Project) is a program of indicator development and application that has grown from 7 hospitals in 1987 to more than 700 hospitals today. METHODOLOGY: Expert panels help to create sets of indicators that describe events involved in a specific sequence of patient care. Each hospital collects data elements for the 21 indicators on a quarterly basis using specifically designed data-collection software. Indicator data are adjusted for case complexity, risk of adverse outcomes, and patient group characteristics. A report is developed that states the rate of occurrence of each indicator and how the hospital's indicator rate compares to other hospitals in the database. Hospitals then use this information to determine if specific processes in their delivery of care yield results that deviate from those of other hospitals. The QI Project promotes regional sharing of information about specific hospital initiatives that might benefit other participants. It also provides a model to use in interpreting what the indicator data reveal about hospital performance. OPERATIONAL ISSUES: QI Project is testing process indicators for patient-level and service-level data to supplement current aggregate-level trend and profile analysis. Indicator data are shared solely with participating systems, but changes in the confidentiality policy are being studied. Reliability assessment surveys are periodically conducted. EXAMPLES: Case studies portray improvement of processes prompted by indicator data for unscheduled admission following ambulatory surgery, for surgical wound infections, and for reducing emergency room waiting times. CONCLUSIONS: The chief contribution of the QI Project and similar projects may not be that they identify all issues of quality, but rather that they may help develop a generation of hospital professionals who will be better able to quantify, evaluate, and improve health care quality.

Confidentiality↗
PubMedDate not supplied

On interpretation of well-known topological indices.

Many topological indices lack an interpretation in terms of simple physicochemical quantities. We have reexamined the structural interpretation of well-known topological indices: the connectivity index (1)chi, the Wiener index W, and the Hosoya topological index Z. We relate the success of various indices in structure-property studies to the degree to which they differentiate contributions from more exposed terminal bonds and more buried interior bonds. When considering bond additive properties of alkanes we find better regressions when greater weights are assigned to terminal CC bonds and lesser weights to internal CC. We suggest here that topological indices be discussed in terms of their partitioning into bond contributions, which for different indices and different bonds will assume different values. With this insight we modified the Wiener index W into a new index W, in which bond contributions are determined using the reciprocal of the product of the number of atoms on each side of a bond. Similarly we modified the Hosoya index Z into Z in which the frequency of occurrence of individual CC bonds in the patterns of disjoint bonds are considered. Novel indices are compared with other indices and they show to yield better regressions for boiling points of octane isomers. This suggests a useful classification of topological indices based on the relative magnitudes of the contributions of terminal and interior bonds. To extend such considerations to other indices one needs to consider partitioning of global molecular indices into bond additive terms. A general scheme for partitioning of molecular descriptors into bond contributions is outlined for indices derived from a selection of matrices associated with molecular graphs.

Journal Article↗
PubMed2000

Early experience with clinical indicators in surgery.

BACKGROUND: In 1997 a set of 53 clinical indicators developed by the Royal Australasian College of Surgeons (RACS) and the Australian Council on Healthcare Standards (ACHS) Care Evaluation Programme (CEP), was introduced into the ACHS Evaluation and Quality Improvement Programme (EQuIP). The clinical indicators covered 20 different conditions or procedures for eight specialty groups and were designed to act as flags to possible problems in surgical care. METHODS: The development process took several years and included a literature review, field testing, and revision of the indicators prior to approval by the College council. In their first year 155 health-care organizations (HCO) addressed the indicators and this rose to 210 in 1998. Data were received from all states and both public and private facilities. RESULTS: The collected data for 1997 and 1998 for some of the indicators revealed rates which were comparable with those reported in the international literature. For example, the rates of bile duct injury in laparoscopic cholecystectomy were 0.7 and 0.53%, respectively; the mortality rates for coronary artery graft surgery were 2.5 and 2.1%, respectively; the mortality rates after elective abdominal aortic aneurysm repair were 2.5 and 3.7%, respectively; and the post-tonsillectomy reactionary haemorrhage rates were 0.9 and 1.3%, respectively. Results for some indicators differed appreciably from other reports, flagging the need for further investigation; for example, the negative histology rates for appendectomy in children were 18.6 and 21.2%, respectively, and the rates for completeness of excision of malignant skin tumours were 90.7 and 90%, respectively. The significance of these figures, however, depends upon validation of the data and their reliability and reproducibility. Because reliability can be finally determined only at the hospital level they are of limited value for broader comparison. CONCLUSION: The process of review established for the indicator set has led to refinement of some indicators through improvement of definitions, and to a considerable reduction in the number of indicators to 29 (covering 18 procedures), for the second version of the indicators (which was introduced for use from January 1999). The clinical indicator programme, as it has with other disciplines, hopefully will provide a stimulus to the modification and improvement of surgical practice. Clinician ownership should enhance the collection of reliable data and hence their usefulness.

Biomarkers↗
PubMed2000

A comparison of fluorescent Ca2+ indicator properties and their use in measuring elementary and global Ca2+ signals.

Quantifying the magnitude of Ca2+ signals from changes in the emission of fluorescent indicators relies on assumptions about the indicator behaviour in situ. Factors such as osmolarity, pH, ionic strength and protein environment can affect indicator properties making it advantageous to calibrate indicators within the required cellular or subcellular environment. Selecting Ca2+ indicators appropriate for a particular application depends upon several considerations including Ca2+ binding affinity, dynamic range and ease of loading. These factors are usually best determined empirically. This study describes the in-situ calibration of a number of frequently used fluorescent Ca2+ indicators (Fluo-3, Fluo-4, Calcium Green-1, Calcium Orange, Oregon Green 488 BAPTA-1 and Fura-Red) and their use in reporting low- and high-amplitude Ca2+ signals in HeLa cells. All Ca2+ indicators exhibited lower in-situ Ca2+ binding affinities than suggested by previously published in-vitro determinations. Furthermore, for some of the indicators, there were significant differences in the apparent Ca2+ binding affinities between nuclear and cytoplasmic compartments. Variation between indicators was also found in their dynamic ranges, compartmentalization, leakage and photostability. Overall, Fluo-3 proved to be the generally most applicable Ca2+ indicator, since it displayed a large dynamic range, low compartmentalization and an appropriate apparent Ca2+ binding affinity. However, it was more susceptible to photobleaching than many of the other Ca2+ indicators.

Aniline Compounds↗
PubMed2005

Indicators for chemicals: sources, impacts and policy performance.

BACKGROUND: Different types of indicators have been developed to describe the impact of chemicals on society and environment. Due to the high number of substances and their different types of use, most of these indicators are directed to specific areas of interest--regarding workplace safety, environmental health or consumer health. They address a specific subset of chemicals and can be used for monitoring enterprise-specific, national or international management measures. MAIN FEATURES: A survey of existing indicators for chemicals has shown that indicators already exist for a remarkable number of problem fields. As soon as the release and the environmental fate of chemicals are taken into account, the complexity of the approaches increases considerably. The distinction between indicators for drivers, pressures, state, impacts and responses, as proposed by the European Environmental Agency, supports the identification of proper indicators for a specific type of problem. DISCUSSION AND CONCLUSIONS: No single indicator exists which is able to cover the whole range of chemicals and their applications. Several indicator approaches cover at least a subset of the most relevant substances. If they are intended to be used for European monitoring, robust data must be provided by EU Member States. Chemicals in enterprises (ancillary inputs as well as process chemicals) are an important element of in-plant material flow management--in terms of occupational safety and health as well as environmental protection. Existing indicators for hazardous chemicals can be a valuable tool for process and product refinement regarding hazardous chemicals, especially for enterprises. OUTLOOK: Indicators for production and impact of chemicals, as well as policy performance indicators, are essential elements in order to monitor the management of chemicals. They have to be established for the national and for the EU level.

Data Collection↗
PubMed1989

Calcium signals recorded from two new purpurate indicators inside frog cut twitch fibers.

Two new Ca indicators, purpurate-3,3'diacetic acid (PDAA) and 1,1'-dimethylpurpurate-3,3'diacetic acid (DMPDAA), were synthesized and used to measure Ca transients in frog cut muscle fibers. These indicators are analogues of the purpurate components of murexide and tetramethylmurexide, in which two acetate groups have been incorporated into each molecule to render it membrane impermeant. The apparent dissociation constant for Ca is 0.95 mM for PDAA and 0.78 mM for DMPDAA. One of the indicators was introduced into a cut fiber, which was mounted in a double Vaseline-gap chamber, by diffusion from the end-pool solutions. The time course of indicator concentration, monitored optically in the middle of the fiber in the central-pool region, suggests that 19% of the PDAA or 27% of the DMPDAA became bound or sequestered inside the fiber. In resting fibers, the absorbance spectrum of either indicator was well fitted by the indicator's [Ca] = 0 mM cuvette absorbance spectrum, which is consistent with the idea that PDAA and DMPDAA do not enter the sarcoplasmic reticulum as tetramethylmurexide appears to be able to do (Maylie, J., M. Irving, N.L. Sizto, G. Boyarsky, and W. K. Chandler, 1987. Journal of General Physiology. 89:145-176). After an action potential, the absorbance of either indicator underwent a rapid and transient change that returned to the prestimulus baseline within 100-200 ms. The amplitude of this change had a wavelength dependence that matched the indicator's Ca-difference spectrum. The average amplitude of peak free [Ca] was 21 microM (PDAA or DMPDAA) if all the indicator inside a fiber was able to react with Ca as in cuvette calibrations, and was 26 (PDAA) or 28 microM (DMPDAA) if only freely diffusible indicator could so react. These results suggest that PDAA and DMPDAA are the first Ca indicators that provide a reliable estimate of both the amplitude and time course of (the spatial average of) free [Ca] in a twitch muscle fiber after an action potential.

Action Potentials↗
PubMed2002

Standard indicators of deprivation: do they disadvantage older people?

BACKGROUND: ecological studies using standard generic indicators of material deprivation have suggested that there is little social inequality at older ages. This may be because the indicators used were designed for studying younger populations and may be biased against older people. OBJECTIVE: to examine the association, at different ages, between mortality ratios, indicators of deprivation and an indicator of poverty, which can be easily tailored to different age groups. METHODS: an ecological study comparing mortality ratios and indicators of deprivation and poverty. We calculated standardised mortality ratios for those under and over 75 years, using all deaths for Northern Ireland between 1990 and 1998. We calculated levels of income support uptake (a social security benefit) for similar age groups. We derived three commonly used indicators of deprivation (Townsend, Carstairs and Jarman) from census data. We assessed the strength of association between the mortality ratios and the indicators of poverty and deprivation using Pearson correlation coefficients. RESULTS: 11.1% of people under 75 and 24.3% of those over 75 were on income support. Income support uptake for those over 75 was strongly correlated with deprivation indicators. There was a much weaker relationship between disadvantage and mortality at older ages, especially in women. Poverty, as measured by income support ratios, was more highly correlated with mortality than any other deprivation indicator-especially at older ages and in women, where income support uptake produced the highest correlations. CONCLUSIONS: many of the commonly used indicators of deprivation are poorly suited to studying inequalities in health in older people. Uptake of income support offers many advantages over conventional indicators.

Adolescent↗
PubMed2004

Comparison of comorbidity indices for patients with head and neck cancer.

BACKGROUND: Comorbidity is an important prognostic factor for elderly patients with head and neck cancer. Investigators are faced with the dilemma of selecting the appropriate comorbidity instrument for outcomes research in cancer. The goal of this study was to compare 2 general comorbidity indices with 2 disease-specific indices. METHODS: The Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database was used to identify 15,493 patients with incident squamous cell carcinomas of the oral cavity, pharynx, and larynx first diagnosed between December 1983 and December 1994. Comorbid ailments were identified through the use of the International Classification of Diseases, 9th edition codes in the Medicare inpatient and outpatient claims for 7131 patients. The overall severity of comorbidity was classified according to 2 general comorbidity indices: the Charlson Comorbidity Index and the Klabunde Index, and 2 disease-specific indices: the Washington University Head and Neck Index and the Head and Neck Cancer Index. Overall survival was the primary end point. Cox proportional hazards analysis was used to assess the performance and discrimination of the comorbidity indices. RESULTS: For each of the 4 comorbidity indices, there was a weak trend of worse survival with higher levels of comorbidity. The 2 general indices performed as well as the 2 disease-specific indices and no instrument clearly performed better than the others. CONCLUSION: Both the general and disease-specific comorbidity indices provided important prognostic information. The disease-specific indices did not perform better than the general indices. In this claims-based analysis, there was no apparent advantage to using a disease-specific index when attempting to predict overall survival.

Aged↗
PubMed2006

Repeat cesarean delivery: what indications are recorded in the medical chart?

BACKGROUND: National surveillance estimates reported a troubling 63 percent decline in the rate of vaginal birth after cesarean delivery (VBAC) from 1996 (28.3%) to 2003 (10.6%), with subsequent rising rates of repeat cesarean delivery. The study objective was to examine patterns of documented indications for repeat cesarean delivery in women with and without labor. METHODS: We conducted a population-based validation study of 19 nonfederal short-stay hospitals in Washington state. Of the 4,541 women who had live births in 2000, 11 percent (n = 493) had repeat cesarean without labor and 3 percent (n = 138) had repeat cesarean with labor. Incidence of medical conditions and pregnancy complications, patterns of documented indications for repeat cesarean delivery, and perioperative complications in relation to repeat cesarean delivery with and without labor were calculated. RESULTS: Of the 493 women who underwent a repeat cesarean delivery without labor, "elective"(36%) and "maternal request"(18%) were the most common indications. Indications for maternal medical conditions (3.0%) were uncommon. Among the 138 women with repeat cesarean delivery with labor, 60.1 percent had failure to progress, 24.6 percent a non-reassuring fetal heart rate, 8.0 percent cephalopelvic disproportion, and 7.2 percent maternal request during labor. Fetal indications were less common (5.8%). Breech, failed vacuum, abruptio placentae, maternal complications, and failed forceps were all indicated less than 5.0 percent. Women's perioperative complications did not vary significantly between women without and with labor. Regardless of a woman's labor status, nearly 10 percent of women with repeat cesarean delivery had no documented indication as to why a cesarean delivery was performed. CONCLUSIONS: "Elective" and "maternal request" were common indications among women undergoing repeat cesarean delivery without labor, and nearly 10 percent of women had undocumented indications for repeat cesarean delivery in their medical record. Improvements in standardization of indication nomenclature and documentation of indication are especially important for understanding falling VBAC rates. Future research should examine how clinicians and women anticipate, discuss, and make decisions about childbirth after a previous cesarean delivery within the context of actual antepartum care.

Adult↗
PubMed2006

A global indicator for biological invasion.

"Trends in invasive alien species" is one of only two indicators of threat to biodiversity that form part of the Convention on Biological Diversity's (CBD) framework for monitoring progress toward its "2010 target" (i.e., the commitment to achieve by 2010 a significant reduction in the current rate of biodiversity loss). To date, however, there is no fully developed indicator for invasive alien species (IAS) that combines trends, derived from a standard set of methods, across species groups, ecosystems, and regions. Here we provide a rationale for the form and characteristics of an indicator of trends in IAS that will meet the 2010 framework goal and targets for this indicator. We suggest single and composite indicators that include problem-status and management-status measures that are designed to be flexible, readily disaggregated, and as far as possible draw on existing data. The single indicators at national and global scales are number of IAS and numbers of operational management plans for IAS. Global trends in IAS are measured as the progress of nations toward the targets of stabilizing IAS numbers and the implementation of IAS management plans. The proposed global indicator thus represents a minimum information set that most directly addresses the indicator objective and simultaneously aims to maximize national participation. This global indicator now requires testing to assess its accuracy, sensitivity, and tractability. Although it may not be possible to achieve the desired objective for a global indicator of biological invasion by 2010 as comprehensively as desired, it seems possible to obtain trend estimates for a component of the taxa, ecosystems, and regions involved. Importantly, current indicator development initiatives will also contribute to developing the mechanisms necessary for monitoring global trends in IAS beyond 2010.

Animals↗
PubMed2005

Renal Doppler resistance indices are associated with systemic atherosclerosis in kidney transplant recipients.

BACKGROUND: In kidney transplant recipients, increased intrarenal resistance indices measured by duplex ultrasound are associated with poor subsequent allograft performance. It remains unclear whether high resistance indices rather reflect local renal damage or systemic vessel disease. We hypothesized that resistance indices are associated with cardiovascular risk factors and with subclinical systemic atherosclerosis in transplant recipients. METHODS: In 105 renal transplant recipients, categories of risk for coronary heart disease were determined by Framingham risk scoring. Intrarenal resistive index (RI) and pulsatility index (PI) were measured in segmental arteries at five representative locations. For assessment of subclinical atherosclerosis, common carotid intima-media thickness, and ankle-brachial blood pressure index (ABI) were determined. RESULTS: Transplant recipients with high coronary risk had higher intrarenal resistance indices than low-risk patients. Higher age, female gender, and lower body mass index were independently associated with increased resistance indices. Renal resistance indices were correlated with common carotid intima-media thickness [RI: r= 0.270 (P= 0.005); PI: r= 0.355 (P < 0.001)]. This association remained significant after adjusting for renal function. Renal resistance indices were increased in patients with pathologic ankle-brachial-indices compared to patients with physiologic ankle-brachial-indices [RI: 73.3 +/- 7.1 vs. 70.2 +/- 6.9 (P= 0.03); PI: 146.4 +/- 29.9 vs. 131.4 +/- 25.9 (P= 0.01)]. Renal resistance indices were neither significantly correlated with glomerular filtration rate (GFR), nor with donor age. CONCLUSION: Intrarenal resistance indices are a complex integration of arterial compliance, pulsatility, and peripheral resistance. They are associated with traditional cardiovascular risk factors as well as with subclinical atherosclerotic vessel damage and should thus not be considered specific markers of renal damage.

Adult↗
PubMed2000

Indicator dilution methods for measuring blood flow, volume, and other properties of biological systems: a brief history and memoir.

In 1824 Hering introduced an indicator-dilution method for measuring blood velocity. Not until 1897 was the method extended by Stewart to measure blood (volume) flow. For more than two decades, beginning in 1928, Hamilton and colleagues measured blood flow, including cardiac output. They proposed that the first-passsage indicator concentration-time curve could be recovered from observed curves that included recirculation by semilogarithmic extrapolation of the early downslope. Others followed with attempts to fit the complete first-passage curve by various forms, such as by the sum of three exponential terms (three well-stirred compartments in series). Stephenson (1948) thought of looking at indicator-dilution curves as convolutions of indicator input with a probability density function of traversal times through the system. Meier and I reached a similar conclusion, and extended it. The fundamental notion is that there exists a probability density function of transit times, h(t), through the system. We proved that mean transit time t= V/F, where V is volume in which the indicator is distributed. Thus, V, F, and t might all be calculated, or r alone might suffice if one wanted only to know relative blood flow. I extended the analysis to include residue detection of indicator remaining in the system, so that V, F, and could be calculated by external monitoring. Chinard demonstrated the value of simultaneous multiple indicator-dilution curves with various volumes of distribution. Goresky extended the technique to study cell uptake and metabolism. He also found a transform of indicator-dilution output curves (equivalent to multiplying the ordinate by tand dividing the time by t) which made congruent the family of unalike curves obtained by simultaneous injection of indicators with different volumes of distribution. Bassingthwaighte showed the same congruency with the transform of outputs of a single indicator introduced into a system with experimentally varied blood flows. We showed the same congruency for the pulmonary circulation, adding a correction for delays. Success of these transforms suggests that the architecture of the vascular network is a major determinant of the shape of density functions of transit times through the system, and that there is in this architecture, a high degree of self-similarity, implying that the fractal power function is a component in shaping the observed density of transit times. I proposed that the distribution of capillary critical opening pressures, which describes recruitment of vascular paths, may be important in shaping indicator-dilution curves, and that h(t) may be derived from flow-pressure and volume-pressure curves under some circumstances.

Animals↗
PubMed1988

Perforating and non-perforating indications for repeated operations in Crohn's disease: evidence for two clinical forms.

The surgical indications in 770 patients with Crohn's disease undergoing intestinal resection at The Mount Sinai Hospital from 1960-83 have been reviewed. Surgical indications were divided into two principal categories: 375 cases with perforating indications and 395 cases non-perforating. Among 292 patients who underwent second operations for recurrent Crohn's disease, the indications for second operation were closely dependent on the indication for primary resection. Second operations were undertaken for perforating indications much more often among cases where the initial indication had been perforating, than among those whose initial indications had been non-perforating (73% v 29%, p less than 0.00001). This trend to similarities in the indications which bring patients to surgery was maintained within each anatomical category of Crohn's disease and even between second and third operations (p less than 0.001). Operations for perforating indications were followed by reoperation approximately twice as fast as operations for non-perforating indications, whether going from first to second operation (perforating 4.7 v non-perforating 8.8 years, p less than 0.001), or from second to third (perforating 2.3 v non-perforating 5.2 years, p less than 0.005). Crohn's disease thus seems to occur in two different clinical patterns, independent of anatomic distribution. These are a relatively aggressive perforating type and a more indolent non-perforating type, which tend to retain their identities between repeated operations and to influence the speed with which reoperation occurs.

Adult↗
PubMed2004

Practice management performance indicators in academic radiology departments.

PURPOSE: To determine the management performance indicators most frequently utilized in academic radiology departments in the United States. MATERIALS AND METHODS: This investigation met the criteria for an exemption from institutional review board approval. A cross-sectional study in which a validated national survey was sent to members of the Society of Chairmen of Academic Radiology Departments (SCARD) was conducted. The survey was designed to examine the following six categories of 28 performance indicators: (a) general organization, (b) volume and productivity, (c) radiology reporting, (d) access to examinations, (e) customer satisfaction, and (f) finance. A total of 158 variables were included in the analysis. Summary statistics, the chi(2) test, rank correlation, multiple regression analysis, and analysis of variance were used. RESULTS: A response rate of 42% (55 of 132 SCARD members) was achieved. The mean number of performance indicators used by radiology departments was 16 +/- 6.35 (standard deviation). The most frequently utilized performance indicators were as follows: (a) productivity, in terms of examination volume (78% [43 departments]) and examination volume per modality (78% [43 departments]); (b) reporting, in terms of report turnaround (82% [45 departments]) and transcription time (71% [39 departments]); (c) access, in terms of appointment access to magnetic resonance imaging (80% [44 departments]); (d) satisfaction, in terms of number of patient complaints (84% [46 departments]); and (e) finance, in terms of expenses (67% [37 departments]). Regression analysis revealed that the numbers of performance indicators in each category were statistically significant in predicting the total number of performance indicators used (P < .001 for all). Numbers of productivity and financial indicators were moderately correlated (r = 0.51). However, there were no statistically significant correlations between the numbers of performance indicators used and hospital location, hospital size, or department size (P > .4 for all). CONCLUSION: Assessing departmental performance with a wide range of management indicators is not yet an established and standardized practice in academic radiology departments in the United States. Among all indicators, productivity indicators are the most frequently used.

Academic Medical Centers↗