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Administrative use of systems analysis to troubleshoot a problematic work situation.

The deinstitutionalized mentally ill continue to seek housing. The present private nursing home industry has sought to fill this population's needs by expanding their business endeavors to low cost residential facilities. The industry, of course, must seek a profit. These investors, however, lack a thorough understanding of the exact housing needs of the people from whom they seek their profits. Failure to establish a residence with a health stabilizing program sufficiently strong to mitigate the residents' health deficits produces a loss that is both financial and human. Many residential administrators are faced with trying to understand and remedy the situation in which they find themselves. The following case study illustrates this point and offers some administrative tools for assessing and communicating to investors the adjustments necessary in order to promote a profit from providing a residence for health impaired populations.

Administrative Personnel↗

Gastrointestinal imaging: a systems analysis comparing digital and conventional techniques.

OBJECTIVE: The purpose of this study was to compare digital and conventional methods of gastrointestinal imaging based on the cost of image storage and estimated overall costs, radiation exposure to the patient, and duration of the examination. MATERIALS AND METHODS: Our study sample consisted of 128 patients who underwent conventional gastrointestinal studies (64 double-contrast upper gastrointestinal examinations and 64 double-contrast barium enemas) and 139 patients who underwent digital gastrointestinal studies (66 double-contrast upper gastrointestinal examinations and 73 double-contrast barium enemas). The number of images and films for each study was recorded, and the mean cost of image storage and the estimated overall costs for digital versus conventional studies were calculated. Both the duration of fluoroscopy and the time from start to completion of the study were obtained from our radiology information system. From these data, we calculated mean radiation exposure to the patient and the duration of the examination. Finally, referring physicians completed a questionnaire about their level of satisfaction with paper prints generated from digital gastrointestinal studies. RESULTS: When digital studies were compared with conventional studies, the mean cost of image storage decreased by 45% and the estimated overall 10-year costs decreased by 8%. The mean number of spot images increased by 8% for upper gastrointestinal examinations and by 25% for barium enema examinations, whereas the mean duration of fluoroscopy decreased by 4% and by 10%, respectively. As a result, radiation exposure to patients increased by only 2%, a difference that did not approach statistical significance. Finally, the mean duration of examinations decreased by 24% for upper gastrointestinal examinations and by 33% for barium enemas. Approximately 85% of the physicians who completed the questionnaires indicated that they reviewed the paper prints generated from digital studies and that they would like to continue receiving them. CONCLUSION: Digital gastrointestinal imaging systems are associated with higher initial costs than conventional systems, but the long-term costs of these digital imaging systems are slightly less because of the lower cost of image storage, and radiation exposure to patients is comparable. The shorter duration of digital examinations is a potential benefit of this technology, allowing improved patient throughput. Finally, referring physicians have a high level of satisfaction with paper prints generated from digital imaging.

Attitude of Health Personnel↗

Langerhans cells in cutaneous tumours: immunohistochemistry study using a computer image analysis system.

Immunohistochemistry, based on antibody anti-S100 protein, was used to evaluate the Langerhans cells (LC) in benign and malign skin neoplasias. These cells were quantitatively estimated using a computer image analysis (OPTIMAS software system, Version 6.1) in skin biopsies diagnosed as basal cell carcinoma (BCC), epidermoid carcinoma (EpC), trichoepithelioma (TE), keratoacanthoma (KA), seborreic keratosis (SK) and actinic keratosis (AK). The antibody anti-S100 protein recognized them. No significant variations were observed in the number of LC among malignant tumour (BCC = 23.25 +/- 5.81 and EpC = 20.88 +/- 4.24). Benign lesions (AK = 33.04 +/- 7.11; TE = 55.74 +/- 9.35; SK = 42.38 +/- 9.92, and KA = 47.62 +/- 10.4) presented a higher number of LC when they were compared among them and to malignant and normal tissues. No significant differences were observed in LC area and volume between benign and malign neoplasias. These results indicate possibly differences in the immunogenicity between benign and malign epidermic tumours. In conclusion, the experimental computer assessment method was reliable and consistent to morphometric analysis of tumoural tissues.

Aged↗

GENOMIZER: an integrated analysis system for genome-wide association data.

Genome-wide association analysis appears to be a promising way to identify heritable susceptibility factors for complex human disorders. However, the feasibility of large-scale genotyping experiments is currently limited by an incomplete marker coverage of the genome, a restricted understanding of the functional role of given genomic regions, and the small sample sizes used. Thus, genome-wide association analysis will be a screening tool to facilitate subsequent gene discovery rather than a means to completely resolve individual genetic risk profiles. The validation of association findings will continue to rely upon the replication of "leads" in independent samples from either the same or different populations. Even under such pragmatic conditions, the timely analysis of the large data sets in question poses serious technical challenges. We have therefore developed public-domain software, GENOMIZER, that implements the workflow of an association experiment, including data management, single-point and haplotype analysis, "lead" definition, and data visualization. GENOMIZER (www.ikmb.uni-kiel.de/genomizer) comes with a complete user manual, and is open-source software licensed under the GNU Lesser General Public License. We suggest that the use of this software will facilitate the handling and interpretation of the currently emerging genome-wide association data.

Chromosome Mapping↗

[Reported malpractice after postoperative infection of the locomotor system. Analysis of 261 expert testimony evaluations].

Postoperative infection in the locomotor system may lead to malpractice suits. The aim of the study was to determine the success rate of these claims and the type of expert-confirmed medical negligence so that strategies for avoiding such negligence can be offered. A total of 261 degrees concerning suspected malpractice after postoperative infection in the locomotor system were retrospectively evaluated. Of these, 43.7% claims were successful. The most frequent type of negligence was late diagnosis (34.2%), followed by inconsistent treatment (27.2%) and insufficient surgical revision (5.3%). In 33.3%, combined types of negligence were found. Most frequently, negligence was suspected after infection following hand surgery and internal fixation of long bones. The highest success rate of claims was seen after puncture of joints (69.2%). Insufficient documentation was confirmed in 15.3%. The majority of negligence resulted from diagnostic and therapeutic doubts, which could be avoided, e.g., by a clear definition of infection, consultation of a second opinion, a 2nd-look operation, undelayed and radical surgical revision, painstaking follow-up and disciplined documentation.

Documentation↗

[Malformations of the central nervous system: analysis of 157 pediatric autopsies].

The malformations of the central nervous system affect about 5 to 10 children per 1000 births. We studied the central nervous system malformations in 5837 pediatric autopsies performed in the Sector of Anatomic Pathology, Hospital de Clínicas-UFPR, between 1960 and 1995. There were 157 central nervous system malformations (2.69%), the commonest were neural tube defects (61%): 47 cases of anencephaly and 45 cases classified in the group of myeloencephaloceles. The anomalies of the prosencephalic evagination corresponded to 8% of all central nervous system malformations, with seven cases of holoprosencephaly. Posterior fossa malformations occurred in 3%, with three cases of Arnold-Chiari. In the present study, the mortality rate due to central nervous system malformations was higher in the neonatal period.

Adolescent↗

[The possible mechanisms of the plastic reorganizations of neuronal activity under different regimens of intracellular electrostimulation based on data from systems analysis methods].

Effects of rhythmical, random and associative intracellular stimulation were studied in identified single neurons of isolated CNS of the Lymnaea stagnalis snail under the conditions of computer controlled experiment. By means of cluster, correlation, and factor methods of analysis were evaluated and compared changes of the character of spontaneous discharge activity induced by above mentioned modes of stimulation. Connections of the basic frequency and temporary characteristics of the endogenous activity of neurons with parameters of external influences were shown to be revealed only during stimulation associated with certain components of endogenous rhythmicity. These connections were practically absent during rhythmical and random stimulation. Three factors were separated which determine the formation of the structure of spike impulsation at application of suprathreshold stimuli. By their variables' composition the factors may be interpreted as: 1) factor of intensity of spontaneous activity; 2) factor of variability of interspike intervals; 3) reinforcing factor. Possible cellular mechanisms of adaptive reorganization of spontaneous activity under the conditions of associative influences are discussed.

Animals↗

Characterization of increased synthesis of acute phase proteins from plasma concentration measurements: a system analysis of the ideal situation with use of computer simulation.

A method for characterizing the secretion of acute phase proteins in vivo from serial plasma concentration measurements is presented. By using a simple two-compartment model it was found that descriptive parameters could be derived from the time course of the increased plasma concentration of the protein. It was assumed that the secretion of an acute phase protein is adequately described by: (i) the start time t1; (ii) the end time t2; (iii) the magnitude of increased flux of the protein from synthetic sites to the extracellular space, described by a turnover index, S. The influence of sampling interval and analytical precision on the reliability of the estimated parameter values was investigated in the ideal situation by using computer simulation. It was found that informative estimates of the secretion rate of an acute phase protein could be obtained provided a fairly high analytical precision with a coefficient of variation less than or equal to 0.01 and using a sampling interval between 0.5--2 h.

Adrenocorticotropic Hormone↗

A systems analysis approach for studying the effect of reproduction-enhancing biotechnologies on the genetic improvement of beef cattle.

A function is presented to which nonlinear programming techniques could be applied to quantify the potential of super-ovulation, embryo transfer, sexed semen, in vitro fertilization and in vitro maturation of oocytes used singularly or in combination to improve genetically beef cattle growth and(or) reproductive efficiency. The function to be maximized adds genetic gain times the sale price of the additional product brought about by the genetic selection program, and any income change due to change from the normal replacement rate of females, and subtracts the additional costs of the breeding program over a random breeding program. All this is expressed on a per-calf-sold basis to arrive at the economic return of the breeding program per calf raised to market age. The rate of increase in inbreeding can be restricted as desired. It is assumed that a progeny testing procedure is practiced for the selection of sires. The power of nonlinear programming to find maximums of functions with many variables and to measure how sensitive the genetic and economic returns are to various success rates for the biotechnologies mentioned above is discussed.

Animals↗

Diagnosis, size estimation and prediction of acute myocardial infarction from S-myoglobin observations. A system analysis to assess the influence of various sources of variability.

Three different ways of using S-myoglobin observations for early diagnosis of acute myocardial infarction have been investigated by computer simulation techniques, viz. classification based on (i) single determination in relation to a decision limit, (ii) the peak serum concentration value, (iii) estimated or predicted value of infarct size from serial serum concentration determinations. The results of the in numero experiments indicate that it is possible to define optimal conditions with regard to time, period and frequency of observation, as well as to assess requirements on pre-analytical/analytical variation. The optimal time for a single observation should be about 10-12 h after onset of symptoms. The influence of pre-analytical/analytical variation is not very critical in this connection and the quality requirements are achievable in the clinical chemical laboratory today (total CV about 0.10). The peak serum value has good diagnostic power, but does not provide a good index of infarct size, no matter how good the analytical quality may be. It should be possible to predict infarct size from early serial S-myoglobin observations. A coefficient of pre-analytical/analytical variation below 0.05 is then required in addition to frequent blood specimen collection from admission up to peak time of the serum concentration curve.

Humans↗

Systems analysis of effector caspase activation and its control by X-linked inhibitor of apoptosis protein.

Activation of effector caspases is a final step during apoptosis. Single-cell imaging studies have demonstrated that this process may occur as a rapid, all-or-none response, triggering a complete substrate cleavage within 15 min. Based on biochemical data from HeLa cells, we have developed a computational model of apoptosome-dependent caspase activation that was sufficient to remodel the rapid kinetics of effector caspase activation observed in vivo. Sensitivity analyses predicted a critical role for caspase-3-dependent feedback signalling and the X-linked-inhibitor-of-apoptosis-protein (XIAP), but a less prominent role for the XIAP antagonist Smac. Single-cell experiments employing a caspase fluorescence resonance energy transfer substrate verified these model predictions qualitatively and quantitatively. XIAP was predicted to control this all-or-none response, with concentrations as high as 0.15 microM enabling, but concentrations >0.30 microM significantly blocking substrate cleavage. Overexpression of XIAP within these threshold concentrations produced cells showing slow effector caspase activation and submaximal substrate cleavage. Our study supports the hypothesis that high levels of XIAP control caspase activation and substrate cleavage, and may promote apoptosis resistance and sublethal caspase activation in vivo.

Apoptosis↗

Severe problem behaviors related to social interaction. 2: A systems analysis.

The effects of problem behavior displayed by two groups of children with developmental disabilities was investigated. One group of children exhibited problem behavior under conditions of low adult attention and was referred to as the attention-seeking or AS behavior profile group. A second group of children exhibited problem behavior under conditions of high adult attention and was referred to as the socially avoidant or SA behavior profile group. A third group of nonproblem children (NP) was examined for comparison purposes. Pairs of children were placed in a teaching situation, and the effects of child problem behavior upon adult instructional behavior were measured. Results indicated that child behavior affected adult behavior and that different child behavior profiles affected adults differentially. Adults responded to the problem behaviors of the AS behavior profile group by increasing attention, providing higher levels of physical contact, and presenting academic tasks that required continuous adult-child interaction. Conversely, the same adults responded to the problem behaviors of the SA behavior profile group by reducing attention, providing lower levels of physical contact, and presenting academic tasks that required little adult-child interaction. The data indicated that these child effects were powerful, immediate, and durable. Theoretical implications concerning reciprocal social influence and the operant theory of child problem behavior are discussed. Applied implications concerning treatment selection and maintenance are also explored.

Adult↗

[Brief acoustic stimuli for the recording of brain stem potentials by computer controlled system analysis].

Brief acoustic stimuli are used in the objective assessment of the auditory threshold and in topodiagnosis of pathological processes in the auditory path via registration of brain stem potentials. The type of stimulus, duration, frequency and phase are decisive for the evocation of the brain stem potentials. However, it is still a somewhat unsolved problem as to how to obtain an optimally reproducible kind of stimulation. The pattern of progression of acoustic stimuli is of crucial importance for the recording of early acoustic evoked potentials (EAEP). Using an artificial auditory canal, a measurement device was constructed for recording acoustic stimulus sequences in the auditory meatus. With the help of electronic monitoring it became possible to produce digitally controlled stimulation resulting in utilizing forms of electrical stimuli which cannot be produced in the audiometer, for obtaining suitable electric stimuli. Whereas the curves of the acoustic pressures largely deviate from those of the electrical stimuli, as shown by measurements in the artificial auditory canal (the deviations depending on the headphones used in each case), the transmission properties of the electro-acoustic transducers are processed mathematically on the basis of Fourier's transformation, and such processing makes it possible to electrically produce any desired sequences of acoustic stimuli, taking the transmission properties of the headphones into account. In this manner, synchronous discharging of the sensory cells by brief acoustic stimuli, which is required for EAEP recording, can be optimized.

Acoustic Stimulation↗

System analysis of Phycomyces light-growth response: double mutants.

The light-growth response of Phycomyces has been studied with Gaussian white-noise test stimuli for a set of 21 double mutants affected in all pairwise combinations of genes madA to madG; these genes are associated with phototropism, the light-growth response, and other behaviors. The input-output relations of the light-growth responses of these mutants are represented by Wiener kernels in the time domain and transfer functions in the frequency domain. The results have been analyzed comparatively with those in the preceding papers on wild-type and single mutant strains. Two of the double night-blind mutants (combinations AB and BC) have especially weak, but still detectable, responses. To evaluate possible dynamic interactions among the seven mad gene products, each double-mutant transfer function was analyzed jointly with those of the parental single mutants and wild-type. Specifically, a hypothesis of dynamic independence was rejected at the 5% significance level for the following combinations: AD, AE, AG, BC, BD, BE, BF, BG, CD, CE, CF, DE, DG, and EF. A formal pictorial scheme summarizes the dynamic interactions among the mad gene products, according to this test. The high degree of interactions between the "input" gene products (A, B, and C) and the "output" gene products (D, E, F, and G) suggest that most or all of the sensory transduction pathway for the light-growth response (and phototropism) is contained in a multimolecular complex.

Light↗

Geographic information system analysis of blastomycosis in northern Wisconsin, USA: waterways and soil.

Geographic information systems (GIS) are powerful tools for investigating the ecogeography of environmentally acquired infections. GIS technology was used to geocode and map cases of blastomycosis, by household, of human and dog residents of Vilas County, Wisconsin, USA. Human case households (n = 136) were from a comprehensive street address registry 1979--2001; human controls were 200 random-number selected households from 2001 county tax records. Dog cases (n = 116) were from a consecutive street address registry from a private veterinarian practice, Eagle River; dog controls were 200 random-number selected addresses from the 2001 total practice registry. Where geocoding was not available from existing maps, home sites were visited and geocoded using a handheld global positioning system (n = 61). Waterway characteristics were obtained from the Wisconsin Department of Natural Resources GNIS database, soil type data from the USDA. Data were analysed with chi-square and Mann-Whitney tests; cluster analysis with CrimeStat II software. A disproportionate number of human and dog cases were associated with waterways of the western Eagle River area. Human and dog cases were more commonly near waterways < 500 m elevation (more nutrient rich) (P < or =0.001 for both) and were associated with sands (prone to drought) (P < or = 0.01 for both). When the nearest waterway was a lake, case addresses were more commonly near lakes with <7.6 m maximum depth (more lake mixing) (P <0.05, humans and dogs) but mean depth, type and size of lakes did not differ from controls. Further studies are needed to clarify the nature of these associations.

Animals↗

Pediatric ambulance utilization in a large American city: a systems analysis approach.

BACKGROUND: Research on utilization of ambulances by pediatric patients lacks an objective, reproducible tool for the evaluation of patterns of ambulance use by both the providers and the users of this resource. OBJECTIVES: 1) To develop an objective, diagnosis-based measure of appropriateness of ambulance utilization. 2) To use the measure to evaluate whether Municipal Ambulance Service dispatchers assign ambulances appropriately, and whether parents/caretakers request ambulances appropriately. STUDY DESIGN: 1) Development of the pediatric ambulance need evaluation (PANE) tool: The consensus of an expert panel was used to assign patients arriving by ambulance to three levels of prehospital transport need based upon their ultimate hospital discharge diagnoses, and were as follows: required advanced life support ambulance (ALS); required basic life support ambulance (BLS); required a less acute mode of transport (LAT). 2) Assessment of appropriateness of ambulance assignments by EMS call-receiving operators (CRO) and of ambulance requests by parents/caretakers: Comparison of actual type of ambulance assigned and of need for ambulance, using the PANE tool and hospital admission rates as gold standards. DATA COLLECTION: Level of prehospital transport provided (ALS vs BLS), ultimate ED diagnosis, and ED disposition (admission vs discharge) was collected for each patient from information abstracted from the prehospital and ED records. SETTING: Bellevue Hospital Center and Harlem Hospital Center, two level I trauma centers in New York City, both with Pediatric Emergency Departments staffed 24 hours a day by attending physicians and residents. PATIENT SELECTION: Consecutive sample of 2633 patients, birth to 18 years of age, who arrived to either hospital by ambulance as primary transports from the field over a one-year period. RESULTS: 1) Development of PANE tool: At Bellevue Hospital, 7% of ED visits arrived by ambulance; at Harlem Hospital, 5% arrived by ambulance. Using these ambulance arrivals, 215 diagnoses were identified for inclusion in the PANE tool. An expert panel categorized each diagnosis as requiring ALS, BLS, or LAT, with a high level of interobserver agreement (weighted kappa = 0.793). As a measure of external validity of the PANE, admission rates were highest in the ALS group, next highest in the BLS group, and lowest in the LAT group (chi2 for trend, P < 0.05). 2) Assessment of ambulance assignments and requests: According to the PANE tool, the sensitivity of dispatcher assignment of ALS ambulances was 72 %. Therefore, 28 % of patients who required an ALS ambulance received BLS care. 50% of patients assigned to an ALS ambulance did not require that level of care, and 1/3 of these were categorized by the PANE as not requiring an ambulance at all. CONCLUSIONS: The PANE tool compared favorably to admission rates as a measure of the severity of illness of patients arriving by ambulance. Applying the PANE tool, we conclude that the majority of requests for ambulances are appropriate, and that the majority of the time dispatchers were able to dispatch the appropriate level of care. However, there is room for significant improvement in utilization of ambulances, and tools like the PANE will be useful in achieving this goal.

Adolescent↗

[The systemic analysis of the predictors of clinico-social prognosis in schizotypic pseudoneurotic disorder].

By means of the systemic analytic approach (a correlation-regression analysis) author estimated prognostic significance of clinical characteristics of premorbid, initial period and manifestations of schizotypic pseudoneurotic disorders in terms of the level of social adaptation. 232 patients were observed after the fist hospitalization during 10 years. Criteria of both favorable and unfavorable prognosis of the disease were determined. The best prognosis took place in 7.6% of the patients, moderate--in 53.4% and the worst (maladaptation)--in 38.8% of the cases. A favorable prognosis correlated with poorly differentiated (nonspecific for endogenic diseases) disorders and with lack of personal changes. Meanwhile, an unfavorable prognosis correlated with disorders typical for slow-progredient schizophrenia (polymorphic neurosis-like and affective disorders, deficient changes of the personality and cognitive disorders).

Adaptation, Psychological↗

Information systems analysis approach in hospitals: a national survey.

A survey of 216 hospitals reveals that some hospitals do not conduct cost-benefit analyses or analyze possible adverse effects in feasibility studies. In determining and analyzing system requirements, external factors that initiate the transaction are not examined, and computer-aided software engineering (CASE) tools are seldom used. Some hospitals do not investigate the advantages and disadvantages of using in-house-developed software versus purchased software packages in the evaluation of alternatives. The survey finds that, overall, most hospitals follow the traditional systems development life cycle (SDLC) approach in analyzing information systems.

Cost-Benefit Analysis↗