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PubMed1996

Wisconsin card sorting activated regional cerebral blood flow in first break and chronic schizophrenic patients and normal controls.

Dynamic 133Xe single photon emission computed tomography (SPECT) was used to measure regional cerebral blood flow (rCBF) during the Wisconsin Card Sorting test (WCS) and the Number Matching task (NM) in six never-medicated first break schizophrenic and schizophreniform patients, seven chronic schizophrenic patients, and seven normal controls. Because of a difference in mean age between first break patients and normals, we adjusted rCBF data for age effects using ANCOVA. For age-adjusted absolute superior and middle frontal rCBF bilaterally, we found significantly less activation from NM to WCS in first break patients compared to normals. Similarly, for age-adjusted absolute and relative left middle frontal rCBF, we found significantly less activation in chronics compared to normals. Changes in age-adjusted global cerebral blood flow (gCBF) were not statistically significant among the three groups, but were in the same direction as activated absolute frontal rCBF. Because of the small number of subjects in each group, the results of this study should be regarded as preliminary and interpreted cautiously.

Adolescent↗
PubMed2005

Natural vermiculite as an exchanger support for heavy cations in aqueous solution.

The natural highly charged lamellar silicate vermiculite was investigated as an exchanger matrix in doubly distilled water solution to exchange magnesium inside the lamella with the heavy cations copper, nickel, cobalt, and lead at the solid/liquid interface. The extension of each exchange reaction was dependent on time of reaction, pH, and cation concentration. The maximum time presented the following order Pb2+ < Ni2+ < Cu2+ < Co2+, which corresponds to 12, 24, 48, and 72 h, respectively. The best performance was observed for nickel, as represented by the exchange capacity Nf, which gave values 0.59, 0.76, 0.84, and 0.93 mmol g(-1) for Pb2+ < Co2+ < Cu2+ < Ni2+, respectively. This capacity is dependent on pH interval variation from 1 to 9, being significantly increased in alkaline condition. The isotherm data were adjusted to a modified Langmuir equation and from the data the spontaneous Gibbs free energy was calculated. Linear correlations were obtained through Gibbs free energy or the maximum capacity against the cationic radius plot, with the lowest values for the largest cation lead. An exponential correlation was also observed for the maximum capacity versus enthalpy of hydration plot, indicating a difficulty of the less hydrated cation, lead, in exchanging with magnesium inside the lamellar space, as suggested by the proposed mechanism. The saturated matrices with cations presented a decrease in interlayer distance in comparison with the original vermiculite, which can be related to the hydrated phases, characteristic for each cation, with a lowest value for lead.

Journal Article↗
PubMed1997

Prevention of post splenectomy sepsis: a population based approach.

BACKGROUND: The aim of the study was to prevent the occurrence of serious, overwhelming infection following splenectomy, by a district based initiative. Subjects were residents of Plymouth and Torbay District Health Authority (DHA) who had undergone splenectomy in the past and general practitioners (GPs) within the District. METHODS: District guidelines on the prevention of post splenectomy sepsis were developed and disseminated among local GPs and hospital doctors. Patients who had undergone operative splenectomy were actively traced through GP and hospital information systems so that they could be offered sepsis preventive measures in accordance with the guidelines. Data capture-recapture was used as an ascertainment adjustment method to estimate the district prevalence of alive patients who have had an operative splenectomy. A postal questionnaire of district GPs was undertaken after one year to determine their awareness and use of the guidelines. RESULTS: Eight-eight alive patients who had undergone splenectomy were not previously identified be their GP as being asplenic. They were traced so that they could be offered sepsis preventive measures in line with the local guidelines. The estimated district prevalence of individuals who had had an operative splenectomy after ascertainment adjustment using data capture-recapture is p = 9.75 per 10,000 population [95 per cent confidence interval (CI) (7.87, 11.64) per 10,000]. Out of 367 district GPs, 201 used the local guidelines after one year. CONCLUSIONS: Effective prevention of overwhelming infection following splenectomy requires an active population based approach.

Community Health Planning↗
PubMed1996

Uniform billing data in hospital planning, marketing and clinical guidelines.

Hospitals are major users of inpatient discharge data from the Pennsylvania Health Care Cost Containment Council (PHC4). A hospital planning and marketing executive and a hospital network consultant describe different uses for the data; including planning, competitor analysis, and development of clinical pathways. The PHC4 data are useful because they are reported in a uniform format for all facilities and they provide detailed clinical and financial information. In addition, Pennsylvania's data include an admission severity measure to permit risk adjustment. These data have enabled these institutions to enhance their clinical and financial performance.

Critical Pathways↗
PubMed1999

Evaluation of carcass, live, and real-time ultrasound measures in feedlot cattle: I. Assessment of sex and breed effects.

Carcass and live-animal measures from 1,029 cattle were collected at the Iowa State University Rhodes and McNay research farms over a 6-yr period. Data were from bull, heifer, and steer progeny of composite, Angus, and Simmental sires mated to three composite lines of dams. The objectives of this study were to estimate genetic parameters for carcass traits, to evaluate effects of sex and breed of sire on growth models (curves), and to suggest a strategy to adjust serially measured data to a constant age end point. Estimation of genetic parameters using a three-trait mixed model showed differences between bulls and steers in estimates of h2 and genetic correlations. Heritability for carcass weight, percentage of retail product, retail product weight, fat thickness, and longissimus muscle area from bull data were .43, .04, .46, .05, and .21, respectively. The corresponding values for steer data were in order of .32, .24, .40, .42, and .07, respectively. Analysis of serially measured fat thickness, longissimus muscle area, body weight, hip height, and ultrasound percentage of intramuscular fat using a repeated measures model showed a limitation in the use of growth models based on pooled data. In further evaluation of regression parameters using a linear mixed model analysis, sex and breed of sire showed an important (P < .05) effect on intercept and slope values. Regression of serially measured traits on age within animal showed a relatively larger R2 (62 to 98%) and a smaller root mean square error (RMSE, .09 to 8.85) as compared with R2 (0 to 58%) and RMSE (.31 to 67.9) values when the same model was used on pooled data. We concluded that regression parameters from a within-animal regression of a serially measured trait on age, averaged by sex and breed, are the best choice in describing growth and adjusting data to a constant age end point.

Animal Feed↗
PubMed2000

Using the Veterans Administration National Surgical Quality Improvement Program to improve patient outcomes.

BACKGROUND: The primary goal of collecting quality assurance data is to ultimately improve patient care. The VA National Surgical Quality Improvement Program (NSQIP) provides each station with risk-adjusted morbidity and mortality data on a regular basis. This report of one medical center's use of the risk-adjusted data shows how it can be used to improve patient care. MATERIALS AND METHODS: Risk-adjusted surgical outcome data for Fiscal Year 1996 (FY96) was received from the NSQIP coordinating center. The Salt Lake City VA medical center was identified as a high outlier for morbidity in general surgery. Patient charts were reviewed and data analyzed to determine practice patterns and to determine if there were any provider issues. Data analysis revealed a large number of wound complications and uncovered a practice pattern of closure of contaminated wounds. Using these data and data from the literature, wound infection and disruption prevention protocols were instituted in the fall of 1997. Wound complications from January to December 1996 (preprotocol) and January to December 1998 (postprotocol) were compared using Student's t test. RESULTS: The total number of operations in 1998 was 719 compared with 634 in 1996. Superficial wound infections dropped from 3.6 to 1.7%, while overall wound complications dropped from 5.5 to 2.9%. None of these changes were statistically significant. CONCLUSIONS: Although introduction of wound infection and disruption prevention protocols did not result in a statistically significant decrease in wound complication, it did result in a clinically significant improvement in patient care.

Humans↗
PubMed1995

Data analysis: statistical analysis and use of historical control data.

Survival-adjusted methods for the statistical analysis of tumor data from long-term rodent carcinogenicity studies are described. Although most of these methods require knowledge of whether individual tumors are "fatal" or "incidental," such determinations may be difficult. Several methods for dealing with this and with other data analysis issues are discussed. Historical control tumor data may be useful in the interpretation of rodent carcinogenicity studies, particularly for rare tumors and for borderline effects. Although statistical methods are available for using historical control data in a formal testing framework, the primary difficulty is establishing a database that is truly comparable to the study under evaluation with respect to those factors known to influence tumor occurrence. Major sources of variability in tumor incidence include the animal room environment, dietary factors/body weight, gross necropsy and slide preparation procedures, and histopathology diagnosis. The National Toxicology Program's use of historical control data is briefly described and illustrated.

Adrenal Cortex Neoplasms↗
PubMed2000

Empirical Bayes adjustments for multiple results in hypothesis-generating or surveillance studies.

Traditional methods of adjustment for multiple comparisons (e.g., Bonferroni adjustments) have fallen into disuse in epidemiological studies. However, alternative kinds of adjustment for data with multiple comparisons may sometimes be advisable. When a large number of comparisons are made, and when there is a high cost to investigating false positive leads, empirical or semi-Bayes adjustments may help in the selection of the most promising leads. Here we offer an example of such adjustments in a large surveillance data set of occupation and cancer in Nordic countries, in which we used empirical Bayes (EB) adjustments to evaluate standardized incidence ratios (SIRs) for cancer and occupation among craftsmen and laborers. For men, there were 642 SIRs, of which 138 (21%) had a P < 0.05 (13% positive with SIR > 1.0 and 8% negative with SIR < or = 1.0) when testing the null hypothesis of no cancer/occupation association; some of these were probably due to confounding by nonoccupational risk factors (e.g., smoking). After EB adjustments, there were 95 (15%) SIRs with P < 0.05 (10% positive and 5% negative). For women, there were 373 SIRs, of which 37 (10%) had P < 0.05 before adjustment (6% positive and 4% negative) and 13 (3%) had P < 0.05 after adjustment (2% positive and 1% negative). Several known associations were confirmed after EB adjustment (e.g., pleural cancer among plumbers, original SIR 3.2 (95% confidence interval, 2.5-4.1), adjusted SIR 2.0 (95% confidence interval, 1.6-2.4). EB can produce more accurate estimates of relative risk by shrinking imprecise outliers toward the mean, which may reduce the number of false positives otherwise flagged for further investigation. For example, liver cancer among chimney sweepers was reduced from an original SIR of 2.2 (range, 1.1-4.4) to an adjusted SIR of 1.1 (range, 0.9-1.4). A potentially important future application for EB is studies of gene-environment-disease interactions, in which hundreds of polymorphisms may be evaluated with dozens of environmental risk factors in large cohort studies, producing thousands of associations.

Analysis of Variance↗
PubMed1998

Mayo's older Americans normative studies: category fluency norms.

Age-adjusted normative data are presented for persons over age 55 years on a common measure of category fluency. Further adjustment for education is also provided. These data were obtained as part of a series of projects known collectively as Mayo's Older Americans Normative Studies (MOANS). The normative information provided here should prove useful for characterizing performance on the individual measure of category fluency. In addition, these data should promote greater accuracy in comparing category fluency scores with performance on any other measures with MOANS norms, including tests of letter fluency. Limitations and unique features of MOANS normative data are also discussed.

Aged↗
PubMed2001

Every death counts: measurement of maternal mortality via a census.

Methods for measuring maternal mortality at national and subnational levels in the developing world lag far behind the demand for estimates. We evaluated use of the national population census as a means of measuring maternal mortality by assessing data from five countries (Benin, Islamic Republic of Iran, Lao People's Democratic Republic, Madagascar, and Zimbabwe) which identified maternal deaths in their censuses. Standard demographic methods were used to evaluate the completeness of reporting of adult female deaths and births in the year prior to the census. The results from these exercises were used to adjust the data. In four countries, the numbers of adult female deaths needed to be increased and three countries required upward adjustment of the numbers of recent births. The number of maternal deaths was increased by the same factor as that used for adult female deaths on the assumption that the proportion of adult female deaths due to maternal causes was correct. Age patterns of the various maternal mortality indicators were plausible and consistent with external sources of data for other populations. Our data suggest that under favourable conditions a national census is a feasible and promising approach for the measurement of maternal mortality. Moreover, use of the census circumvents several of the weaknesses of methods currently in use. However, it should also be noted that careful evaluation of the data and adjustment, if necessary, are essential. The public health community is urged to encourage governments to learn from the experience of these five countries and to place maternal mortality estimation in the hands of statistical agencies.

Censuses↗
PubMed2001

Bone quality parameters of the distal radius as assessed by pQCT in normal and fractured women.

The aim of this study was to test the ability of some indicators of different aspects of bone quality (assessed by peripheral quantitative computed tomography in the distal radius) to discriminate between fractured and nonfractured individuals. The study compared 214 women aged 45-85 years, free of any bone-affecting treatment, of whom 107 had suffered a Colles' fracture in the previous 6 months and 107 did not. The determinations included bone tissue or mineral 'mass' indicators (trabecular, cortical and total volumetric mineral content, cortical bone area); bone 'density' estimates (trabecular, cortical and total volumetric mineral density), and the Cartesian (rectangular) and polar moments of inertia as influences of cross-sectional architecture on resistance to bending and torsional loads, respectively. The influences of body height, weight and age on the tomographic indicators were minimized by adjusting the data according to the partial coefficients of multiple stepwise regressions. The adjusted values of all the indicators were lower in fractured than in nonfractured groups. The prevalence of fractures was directly related to the actual values of the indicators, rather than the age or body habitus of the individuals. The significance of these differences between the assessed indicators decreased in the following order: trabecular 'mass' > trabecular 'density' > cortical or total 'mass' > cortical architecture > total or cortical 'density' indicators. Within the same type of bone, the tissue or mineral 'mass' indicators performed better than the 'density' indicators. The cortical bone density did not give useful information, probably because of technical difficulties. Odds-ratios and receiver-operating characteristic (ROC) analyses confirmed those features. The selected 'cut-off' values of the indicators as determined by the ROC curves (very close to those determined by the inflexion points of the logistic reression curves) may indicate reference limits to detect persons at risk of fracture according to the type of information provided by each variable. These results show that these tomographic indicators discriminate well between fractured and nonfractured individuals, and should be suitable to assess how total, cortical and trabecular bone strength in the distal radius could affect different kinds of strength regardless of the age or body habitus of the individual. Their ability to estimate fracture risk from different biomechanical points of view should be assessed by adequately designed, prospective studies.

Aged↗
PubMed2001

Genetic association of an LBP-1c/CP2/LSF gene polymorphism with late onset Alzheimer's disease.

OBJECTIVES: The only locus unequivocally associated with late onset Alzheimer's disease (AD) risk is APOE. However, this locus accounts for less than half the genetic variance. A recent study suggested that the A allele of the 3'UTR biallelic polymorphism in the LBP-1c/CP2/LSF gene was associated with reduced AD risk. Samples were diagnosed predominantly by clinical rather than pathological criteria. We have sought to replicate this finding in a series of necropsy confirmed, late onset AD cases and non-demented controls. METHODS: The 3'UTR polymorphism in the LBP-1c/CP2/LSF gene was typed in 216 necropsy confirmed AD cases and 301 non-demented controls aged >73 years. RESULTS: We found different LBP-1c/CP2/LSF allele distributions in our AD cases and controls (p=0.048); the A allele was associated with reduced AD risk. The allele and genotype frequencies observed in our cases and controls were similar to those previously reported. No significant effects emerged when the data were adjusted for age, sex, or apoE epsilon4 carrier status. CONCLUSIONS: Our data support LBP-1c/CP2/LSF as a candidate gene/risk factor for AD and provide justification for future studies to investigate the role of this gene in Alzheimer's disease.

Age of Onset↗
PubMed1986

Strategic planning for clinical services: St. Joseph Hospital and Health Care Center.

A pharmacy department at a 340-bed community hospital based its strategic plan for developing patient-oriented services on a sound drug distribution system, a credible work-measurement program, and fiscal responsibility. In 1982 the department of pharmacy and i.v. therapy implemented a strategic plan for improving pharmaceutical services. The plan involved developing goals and objectives for the department; marketing the department's services and fiscal management to hospital administrators, medical staff, and nursing staff; building teamwork among the pharmacy staff; and improving the drug distribution system before instituting clinical services. Hiring of additional pharmacy staff was justified on the basis of work-measurement data. By adjusting staffing levels every two weeks based on work-measurement data, the department increased the efficiency of drug distribution activities; the pharmacy also implemented cost-saving programs like selection of therapeutic alternates and formulary restrictions. The savings were then reinvested in labor-intensive patient-oriented pharmaceutical services. A staff development program using staff pharmacists as preceptors expanded the breadth and depth of pharmacists' clinical skills. The planning efforts were successful because the needs of hospital administrators, the pharmacy department, and staff members were addressed.

Hospital Bed Capacity, 300 to 499↗
PubMed1977

Application of a method for correcting an observed regression between change and initial value for the bias caused by random errors in the initial value.

When studying the correlation between the change of a variable during treatment and the value before treatment, random errors (errors of measurement as well as intra-individual biological variation) may yield seriously biased results. In the present work a method to adjust for this bias is presented. The method was applied to data from blood coagulation factor and plasma protein analyses in chronic alcoholics before and after one week of abstinence. It was found that many of the significant correlations were lost when the data were adjusted.

Adult↗
PubMed2005

The global burden of occupational noise-induced hearing loss.

BACKGROUND: Excessive noise is a global occupational health hazard with considerable social and physiological impacts, including noise-induced hearing loss (NIHL). This paper describes the worldwide morbidity of occupational NIHL in the year 2000. METHODS: The proportion of the population exposed to occupational noise was estimated using noise exposure data from the US National Institute for Occupational Safety and Health (NIOSH), adjusted by data on the distribution of the work force by occupational category and economic sector, and economic activity rates in each WHO subregion. These values for the exposed population and risk measures for NIHL were used to develop estimates of the attributable fraction (AF) of adult-onset hearing loss resulting from occupational noise exposure. The AFs were applied to WHO estimates of total disability-adjusted life years (DALYs) from adult-onset hearing loss to estimate the DALYs due to occupational noise. RESULTS: Worldwide, 16% of the disabling hearing loss in adults (over 4 million DALYs) is attributed to occupational noise, ranging from 7% to 21% in the various subregions. The effects of the exposure to occupational noise are larger for males than females in all subregions and higher in the developing regions. CONCLUSIONS: Occupational noise is a significant cause of adult-onset hearing loss. The majority of this NIHL burden can be minimized by the use of engineering controls to reduce the generation of noise at its source.

Adolescent↗
PubMed1993

Utility of Ramfjord index teeth to assess periodontal disease progression in longitudinal studies.

The feasibility of using the Ramfjord index teeth to estimate whole-mouth periodontal disease activity was investigated. Whole-mouth examinations were carried out semi-annually over a 36-month period in 98 maintenance patients previously treated for adult periodontitis. Recurrent periodontitis was defined as either a 3-mm or greater probing depth increase from baseline, or a 2-mm or greater probing depth increase together with 2-mm or greater of relative attachment loss measured from a reference stent. Whole-mouth disease activity was compared to Ramfjord index teeth data, with and without adjustment. Adjustment was made by multiplying disease activity rates on Ramfjord index teeth by the ratio formed from the sum of all teeth present over the sum of all Ramfjord index teeth in the study population. Without adjustment, Ramfjord index teeth markedly underestimated subjects with recurrent disease activity when compared to whole-mouth findings. However, with adjustment, the hypothesis that upper and lower limits on whole-mouth incidence of recurrent periodontitis could be estimated from Ramfjord index teeth disease-activity rates were not rejected (P > 0.20, z-test) at any 6-month interval. At 5 of 6 examinations, the % of disease active subjects as determined from whole-mouth evaluations was below the upper limit for disease incidence calculated, with 95% confidence, from point estimates derived from adjusted Ramfjord index teeth data. Partial-mouth examinations with appropriate adjustment of Ramfjord index teeth data may be useful for assessing periodontal disease progression in longitudinal population studies of human periodontitis.

Adult↗
PubMedDate not supplied

The impact of the transcendental meditation program on government payments to physicians in Quebec.

PURPOSE: This study evaluated whether governmental medical payments in Quebec were affected by the Transcendental Meditation (TM) technique. DESIGN: This retrospective study used a pre- and postintervention design in which government payments for physicians' services were reviewed for 3 years before and up to 7 years after subjects started the technique. Payment data were adjusted for aging and year-specific variation (including inflation) using normative data. No separate control group was used; thus it is impossible to determine whether the changes were caused by the TM program or some other factor. SUBJECTS: A volunteer group of 677 provincial health insurance enrollees was evaluated. The subjects had chosen to practice the TM technique before they were selected to enter the study. The subjects (348 men, 329 women) had diverse occupations. Their average age was 38 years and ranged from 18 to 71 years at the start of the TM program. INTERVENTION: The TM technique of Maharishi Mahesh Yogi is a standardized procedure practiced for 15 to 20 minutes twice daily while sitting comfortably with eyes closed. SETTING: Province of Quebec, Canada. RESULTS: During the 3 years before starting the TM program, the adjusted payments to physicians for treating the subjects did not change significantly. After beginning TM practice, subjects' adjusted expenses declined significantly. The several methods used to assess the rate of decline showed estimates ranging from 5% to 7% annually. CONCLUSIONS: The results suggests that the TM technique reduces government payments to physicians. However, because of the sampling method used, the generalizability of these results to wider populations could not be evaluated.

Adolescent↗