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PubMedDate not supplied

Effect of a telephone medication renewal service on blood pressure control.

OBJECTIVE: To evaluate the effect of a pharmacist-staffed telephone medication renewal service on blood pressure (BP) control. DESIGN: Retrospective review of telephone call logs and patient charts. SETTING: University-based family medicine clinic. PATIENTS AND OTHER PARTICIPANTS: All patients seen at the clinic with an International Classification of Diseases 9 code for hypertension during 2000. INTERVENTIONS: Age, sex, diagnosis of heart failure and/or diabetes, and frequency of clinic visits were recorded. Telephoned prescription renewal requests for 2000 were logged; patient name, age, medication requested, strength, and directions were recorded. Each log entry was reviewed to identify patients requesting a renewal for an antihypertensive agent. Patients with hypertension who used the renewal service were compared with those who did not. MAIN OUTCOME MEASURES: BP control rates were calculated for each group as the number of patients who met BP goals from the 1997 guidelines of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Analysis of variance and regression analysis were performed to examine the effect use of the renewal service had on BP control in both groups of patients. Covariables such as age, sex, and clinic visits were included in the model. RESULTS: Of the 938 patients seen for hypertension, 332 used the renewal service at least once. We found no statistical difference between the two groups with respect to BP control (P = .86; confidence interval [CI], 0.7-1.3). BP control did not improve more for patients who used the renewal service more frequently (P = .48; CI, 0.9-1.2). CONCLUSION: Use of the telephone medication renewal service had no effect on BP control. While increasing patients' access to medications is necessary, the results of this study suggest that this in itself is not sufficient to ensure good BP control.

Antihypertensive Agents↗
PubMed2000

Variation in contrasting forms of 'memorising' and associated observables.

BACKGROUND: There is a posited conceptual distinction in the student learning literature in higher education between contrasting forms of 'memorising': as a process of rehearsal which is usually equated with rote learning, and as a process of committing to memory material that in two separate senses is temporally either 'understood' before or after the event. AIMS: The present study reports on the operationalisation of these contrasting forms of 'memorising' and investigates their empirical association with one another, their gender sensitivity, and their joint association with other modelling sources of explanatory variation in student learning. SAMPLES: Two samples of entering first-year economics students at the Universities of South Australia (N = 896) and Adelaide (N = 448) which are combined in the present study (N = 1344). The combined sample is further distinguishable by gender (females, N = 662, males, N = 682). METHOD: Students were surveyed prior to the commencement of lectures and reported retrospectively on their most recent school-based learning experiences. Resultant data in the form of inventory responses were subjected to exploratory and confirmatory factor analyses, multivariate analysis of variance, and correlation analysis. RESULTS: Empirically the three forms of 'memorising' are independent of one another and they are furthermore sensitive to gender-based response differences in terms of both location and structure. Forms of 'memorising' are respectively associated in a theoretically congruent manner with 'deep'-level processes, learning pathologies, and contrasting conceptions of learning. CONCLUSIONS: The unqualified use of 'memorising' in studies of student learning is contra indicated. Contrasting forms of 'memorising' represent discrete sources of explanatory variation that can be used to construct finer grained models of student learning in process terms.

Adolescent↗
PubMed2002

Routine cervical cerclage in higher order multiple gestation -- does it prolong the pregnancy?

Preterm birth following cervical dilatation is the greatest threat to infants of a multiple pregnancy. Lacking reliable data concerning the effect of prophylactic cerclage, we compared a study group to controls for maternal and perinatal outcome. Sixteen of 94 triplet-, 9 of 18 quadruplet/quintuplet-pregnancies, treated with prophylactic cerclage, were retrospectively compared to those without cervical cerclage respectively. Kruskal-Wallis test and Mann-Whitney-U test were performed as non-parametric one way analysis of variance. For the analysis of frequencies Chi Square test or Fisher's exact test were performed. Odds ratio with 95% confidence interval was used to compare the need for intravenous tocolysis as well as perinatal morbidity and mortality. Gestational age at delivery was not different from the controls in all studied groups. Birth weight revealed a 200 g dominance for the "no cerclage-triplets", while this significant difference was inverted for quadruplets/quintuplets (1245 g vs. 1069 g). With respect to gestational age at birth, need for hospitalisation or medical intervention no benefit was achieved. Moreover, perinatal outcome analysed by arterial pH, APGAR-Score and perinatal mortality was not altered by a prophylactic cerclage. Perinatal morbidity for quadruplets and quintuplets was even higher in cerclage pregnancies. Therefore, these retrospective results disclaim a positive impact of cervical cerclage on pregnancy management or perinatal outcome in multifetal pregnancies.

Apgar Score↗
PubMed2003

Measuring the fit between human judgments and automated alerting algorithms: a study of collision detection.

Methodologies for assessing human judgment in complex domains are important for the design of both displays that inform judgment and automated systems that suggest judgments. This paper uses the n-system lens model to evaluate the impact of displays on human judgment and to explicitly assess the similarity between human judgments and a set of potential judgment algorithms for use in automated systems. First, the need for and concepts underlying judgment analysis are outlined. Then the n-system lens model and its parameters are formally described. This model is then used to examine a previously conducted study of aircraft collision detection that had been analyzed using standard analysis of variance methods. Our analysis found the same main effects as did the earlier analysis. However, n-system lens model analysis was able to provide greater insight into the information relied upon for judgments and the impact of displays on judgment. Additionally, the analysis was able to identify attributes of human judgments that were--and were not--similar to judgments produced by automated systems. Potential applications of this research include automated aid design and operator training.

Accident Prevention↗
PubMed2005

[Association between plasmatic levels of homocysteine and stroke: a transversal analytic study].

PURPOSE: To determine the association of homocysteine with ischemic stroke, considering age, gender, cigarette smoking, hypertension, diabetes and etiology of cerebrovascular disease. METHOD: Transversal analytic observational study of 104 patients with the diagnosis of ischemic stroke and 98 healthy controls had blood homocysteine analyzed by high performance liquid chromatography. Statistics was performed with Student's t and Kruskal-Wallis' tests, analysis of variance, linear regression analysis, logistic regression and Pearson's linear correlation coefficient. RESULTS: Patients had higher values for homocysteine (15.4 +/- 11.7 micromol L(-1)) than controls (10.5 +/- 4.2 micromol L(-1)). Dividing both groups into four groups according to age, significant differences in homocysteine values were found between patients and controls with age 40-49 and 50-59 years. Homocysteine values were significantly higher in patients with hypertension and in those with diagnosis of atherosclerotic cerebrovascular disease. Logistic regression studies showed relationship between atherosclerosis and homocysteine. CONCLUSIONS: Homocysteine is associated with ischemic stroke.

Adult↗
PubMed1996

Study design and statistical analysis of toxicokinetics: a report of JPMA investigation of case studies.

In 1994, the Japanese Pharmaceutical Manufacturers Association (JPMA) conducted a questionnaire survey on case studies of toxicokinetics which were recently conducted its member companies. The present paper summarizes study designs and results of data analysis of 102 cases of repeated oral dose toxicity studies with dogs, monkeys, rats or mice. The statistical analysis of toxicokinetic data introduced in this paper, e.g. log-transformation of concentration data, analysis of variance and regression analysis, may be useful in clarifying the comprehensive effects of test doses, duration of repeated dosing, and sex of test animal on the systemic exposure. Suggestions are made on how experimental design can aid the efficient conduct of toxicokinetic studies in the face of limits on the number of animals.

Animals↗
PubMedDate not supplied

Reminiscence intervention in nursing homes: what and who changes?

The results of experimental studies of reminiscing are not as uniformly optimistic about its therapeutic value as is the theoretical literature. Moreover, anecdotal evidence regarding the impact of reminiscence interventions is more positive than the statistical evidence. This study suggests reasons for these previous findings, and examines data from a discussion group intervention in thirty nursing homes, in which 185 residents completed pre- and posttests. It analyzes the characteristics of participants in relation to modifications in selected attitudes and behaviors over the intervention period. Analysis of variance and discriminant analysis revealed no significant relationships between attitudinal or behavioral modifications and demographic or other characteristics, with one exception. Value-choices made by participants were related to such modifications. The findings are interpreted in terms of the "mental adaptability" of participants and the compensatory nature of reminiscence in an institutional setting.

Adaptation, Psychological↗
PubMed1998

Validation of home blood glucose meters with respect to clinical and analytical approaches.

OBJECTIVE: To evaluate the clinical and analytical accuracy of home blood glucose meters. RESEARCH DESIGN AND METHODS: Six blood glucose meters--Reflolux S (Boehringer Mannheim, Mannheim, Germany), One Touch II (LifeScan, Milpitas, CA), Glucocard Memory (Menarini, Florence, Italy), Precision QID (Medisense, Cambridge, U.K.), HaemoCue (HaemoCue, Angelholm, Sweden), and Accutrend alpha (Boehringer Mannheim, Mannheim, Germany)--were compared with a reference method (Beckman Glucose Analyzer II) under controlled conditions (glucose clamp technique). Validation of the blood glucose meters was accomplished by clinically oriented approaches (error grid analysis), statistical approaches (variance components analysis), and by the criteria of the American Diabetes Association (ADA), which recommend a target variability of < 5%. RESULTS: A total of 1,794 blood glucose monitor readings and 299 reference values ranging from 2.2 to 18.2 mmol/l were analyzed (705 readings < 3.89 mmol/l, 839 readings between 3.89 and 9.99 mmol/l, and 250 readings > 9.99 mmol/l). According to error grid analysis, only Reflolux S and Glucocard M had 100% of estimations within the clinically acceptable zones A and B. Assessment of analytical accuracy revealed substantial differences between the glucose meters after separation of the data into defined glycemic ranges. None of the devices met the ADA criteria. CONCLUSIONS: To evaluate accuracy of blood glucose meters, error grid analysis, as well as statistical models, are helpful means and should be performed together. Analytical performance of currently available home blood glucose meters differs substantially within defined glycemic ranges.

Blood Glucose Self-Monitoring↗
PubMed2000

Associations between alcohol consumption and insulin sensitivity and cardiovascular disease risk factors: the Insulin Resistance and Atherosclerosis Study.

OBJECTIVE: Light-to-moderate alcohol consumption has been associated with reduced cardiovascular disease (CVD) mortality, which may be explained by increased insulin sensitivity (SI) and an improved lipoprotein and blood pressure profile. Prior research has shown improved SI with light-to-moderate alcohol intake even though somewhat imprecise measures of SI were used. RESEARCH DESIGN AND METHODS: Relationships between alcohol use and SI and CVD risk factors were assessed in a cross-sectional analysis of 1,196 white, African-American, and Hispanic men and women from the Insulin Resistance and Atherosclerosis Study (IRAS). Five categories of previous-year alcohol use (never, <0.5 drinks/day, 0.5-0.99 drinks/day, 1-2.99 drinks/day, and > or =3 drinks/day) and log SI + 1 (frequently sampled intravenous glucose tolerance test with Bergman minimal model analysis), log fasting insulin, log triglycerides, HDL cholesterol, and systolic/diastolic blood pressure were examined using analysis of variance. RESULTS: Univariate analysis showed an inverse U-shaped relationship between SI and alcohol intake, with a peak at the 0.5-0.99 drinks/day category. A U-shaped relationship was observed between fasting insulin and the lipid and blood pressure measures. After adjustment for demographic (clinic, sex, ethnicity, age), lifestyle (smoking, dietary energy/fat intake, physical activity), and physical (BMI, waist circumference) variables, the alcohol/insulin association was attenuated, but the association with lipids and blood pressure remained for high-intake categories. CONCLUSIONS: These data suggest that the enhanced SI associated with light-to-moderate alcohol consumption may be a function solely of a BMI and central adiposity profile more favorable to higher SI.

Black or African American↗
PubMed2003

RETR_PWR: an SAS macro for retrospective statistical power analysis.

In contrast to prospective power analysis, retrospective power analysis provides an estimate of the statistical power of a hypothesis test after an investigation has been conducted rather than before. In this article, three approaches to obtaining point estimates of power and an interval estimation algorithm are delineated. Previous research on the bias and sampling error of these estimates is briefly reviewed. Finally, an SAS macro that calculates the point and interval estimates is described. The macro was developed to estimate the power of an F test (obtained from analysis of variance, multiple regression analysis, or any of several multivariate analyses), but it may be easily adapted for use with other statistics, such as chi-square tests or t tests.

Algorithms↗
PubMed1999

Effects of gender and age on plasma levels of clozapine and its metabolites: analyzed by critical statistics.

BACKGROUND: Previous reports concerning the effects of gender and age on steady-state plasma concentrations of clozapine and its major metabolites, norclozapine and clozapine-N-oxide, have been controversial. Since the frequency distribution of the plasma levels is asymmetrical and skewed to the right, the statistical methods (such as analysis of variance and regression analysis) used earlier are actually inappropriate for analyzing the effects of the variables on the concentrations and might contribute to the inconsistent results. The goal of the present study, with befitting statistics, is to measure the potential effect of dose, gender, age, and body weight on plasma levels of clozapine and its 2 major metabolites. METHOD: We retrospectively analyzed data from a therapeutic drug monitoring study for steady-state plasma clozapine, norclozapine, and clozapine-N-oxide levels that was conducted in a large group of Chinese schizophrenic inpatients (male:female ratio = 83:79; age range, 33.8 +/- 9.3 years). The daily doses of clozapine had ranged from 100 to 900 mg, with a mean +/- SD value of 379.5 +/- 142.2 mg. Plasma concentrations had been measured using high-performance liquid chromatography with ultraviolet detection. Multiple linear regression was adopted to quantify the effects of various factors on the plasma levels. The natural logarithm of the plasma level was used as the dependent variable to overcome the skewness problem. RESULTS: After adjusting the effects of gender, age, and body weight by multiple linear regression, each 1-mg increment in the daily dose could raise the clozapine level by 0.31%, norclozapine by 0.27%, and clozapine-N-oxide by 0.16%. Female patients had 34.9% higher clozapine levels and 36.3% higher norclozapine, with other variables being controlled. No sex differences were demonstrated for clozapine-N-oxide levels. Each 1-year increment in age would elevate the clozapine level by 1.1%, norclozapine by 1.0%, and clozapine-N-oxide by 1.0%. Body weight could not influence the levels of these compounds. CONCLUSION: The present results suggest that women possess higher plasma levels (about one third higher) of clozapine and norclozapine, but not the N-oxide metabolite. Each addition of 1 year in age elevated clozapine and either metabolite's levels by about 1%. Furthermore, every 1-mg increase in the daily dose raised clozapine and norclozapine concentrations by approximately 0.3%. These findings could assist clinicians in optimizing clozapine dosing strategies.

Adult↗
PubMedDate not supplied

The importance of decisional balance and self-efficacy in relation to stages of change for fruit and vegetable intakes by young adults.

PURPOSE: To examine the stages of change, decisional balance, and self-efficacy constructs in relation to fruit and vegetable intakes by young adults 18-24 years old. DESIGN: A cross-sectional project was conducted by 10 states in January-July 2000 to examine decisional balance and self-efficacy in relation to stage of change for increasing fruit and vegetable intake among young adults. SUBJECTS: In all, 1545 usable surveys were returned (response rate = 55%). More non-respondents were men and precontemplators than respondents. Sixty-one percent of respondents were women, 90.3% were white, and 49.7% were current students. SETTING: Alabama, Kansas, Maine, Michigan, Nebraska, New York, Rhode Island, Oregon, South Dakota, and Wisconsin. MEASURES: A telephone screening interview and a self-administered mail survey. ANALYSIS: Analysis of variance, principal components analysis, cluster analysis, and chi 2 test. RESULTS: From precontemplation to maintenance, a significant linear trend was found toward higher food intake and self-efficacy for fruits and vegetables. The patterns of shifts in the pros and cons across the stages resembled those of other health behaviors. The decisional balance items were further classified into five component factors that varied significantly in importance across the stages. Four subject clusters were derived (unconcerned, reluctant, exploring, and action-oriented); distribution of the clusters agreed with that of the five stages. CONCLUSIONS: This study supports applicability of the Transtheoretical Model for assessing fruit and vegetable consumption by young adults. Derivation of the four clusters implies the importance of including decisional balance and self-efficacy as outcome measures besides dietary behavior for evaluating the effectiveness of nutrition interventions.

Adolescent↗
PubMedDate not supplied

Statistical optimization of transdermal drug delivery system of terbutaline sulfate by factorial analysis.

A matrix type of transdermal drug delivery system of terbutaline sulfate was designed and developed by full 3(2) factorial method using polyvinyl alcohol (PVA) of medium molecular weight and polyvinyl pyrrolidone (PVP K-30) as matrix forming polymer and propylene glycol as plasticizer. Patches were designed to deliver 62 micrograms/cm2/hr of the drug into the systemic circulation. These were evaluated for in vitro skin permeation study through excised guinea pig skin. The permeation followed Higuchi kinetics, as its coefficients of correlation (r = 0.965-0.978) predominates over other permeation kinetics. Various physico-chemical parameters of the patches were investigated. Statistical optimization of in vitro permeation rate of the drug from the films were evaluated using two way analysis of variance (ANOVA), regression analysis.

Administration, Cutaneous↗
PubMedDate not supplied

Effect of 180-week water storage on the flexural properties of E-glass and silica fiber acrylic resin composite.

PURPOSE: The aim of this study was to determine the effect of long-term water immersion on the flexural properties of fiber-reinforced composite. MATERIALS AND METHODS: Continuous, woven, silanized E-glass fibers and woven silica fibers were used to reinforce heat-cured and autopolymerized denture base polymers. Fibers were oriented at a 45-degree angle to the long axis of the test specimens. Control specimens were unreinforced. Dry test specimens and those stored in water for up to 180 weeks were tested with a 3-point loading apparatus. RESULTS: Ultimate transverse strength and flexural modulus of unreinforced and fiber-reinforced composite test specimens decreased during water storage (P < 0.001, analysis of variance). Post hoc analysis revealed that after the storage of 4 weeks no statistically significant reduction occurred. CONCLUSION: The results of this study suggest that the ultimate transverse strength of the fiber-reinforced composite made from E-glass fibers is reduced by approximately 27% compared to the dry fiber-reinforced composite. The majority of the reduction occurred during 4 weeks of storage in water and remained approximately at that level for 180 weeks.

Acrylic Resins↗
PubMed1979

[Combined effect of alkylating compounds on human chromosomes].

A combined effect of thiophosphamide and dipin on chromosomes of unstimulated human lymphocytes was studied in experiments carried out thrice according to the scheme of a complete two-factor experiment. The exposure to the mutagens lasted for an hour, the concentrations being from 3.17 to 22.19 . 10-5 M. After washing a fresh medium with PHA was added to lymphocytes and then they were cultivated during 60 hrs. Both at separate and combined action of tested chemicals the effect observed in all the cytogenetic tests was not subjected to a linear dependence on the concentration of mutagens. With the change in the proportion between thiophosphamide and dipin, given that the summed number of their molecules was constant, the cytogenetic effect was directly proportional to the part of each mutagen in a combined treatment. The analysis of variance and regression analysis of the results obtained as well as the analysis of types of appearing chromosome aberrations and the analysis of distribution of breaks in cells at the combined action showed that, taking into account that the concentration dependences were not linear. the combined effect of thiophosphamide and dipin was additive, without any interaction of individual effects.

Alkylating Agents↗
PubMed2001

Comparing patients with depressive complaints and patients with chronic medical conditions on their functioning and medical consumption.

BACKGROUND: Several studies have found that depressive complaints are associated with limitations in functioning that are at least comparable with those of chronic medical conditions, such as diabetes or lung diseases. However, the consequences of these associations for the utilization of general health care services are not known, certainly not for health care settings outside the United States. AIMS OF THE STUDY: To investigate the association of depressive complaints with functioning and health care utilization, comparing this with the association of chronic medical conditions with functioning and health care utilization. METHODS: In a community-based sample of Dutch adults (N=9428), chronic conditions (21 types) and depressive complaints were assessed by self-report. Only active conditions and depressive complaints, for which treatment was taking place, were selected for the analyses. Health status and disabilities were also assessed by self-report. Information on the utilization of health care services was based on self-report as well as on data extracted from a claims database. This database also provided information on the use of psychoactive medications. The associations between chronic conditions, depressive complaints and dependent variables were determined by analysis of variance or regression analysis, adjusting for possibly confounding factors (gender, age, living conditions). RESULTS: Depressive complaints, more than any chronic condition (except back problems), were associated with fatigue, poor subjective health and days spent in bed. Those having depressive complaints visited their general practitioner (GP) more often than the others. They also contacted a medical specialist more often than other patient categories, apart from patients with heart diseases. The combination of depressive complaints and chronic medical conditions was not associated with increased utilization or lower functioning. CONCLUSION: Depressive complaints are not only connected to functioning, but also to the utilization of general health care services. The strength of these associations is comparable with that of chronic medical conditions. This study stresses the pertinence of (research on) the management and treatment of patients with depressive complaints in general health care settings.

Journal Article↗
PubMed2002

Anti-Candida antibodies in serum and saliva of patients with denture stomatitis.

OBJECTIVE: Quantitative measurement of IgA and IgG antibodies in the serum and saliva of patients with denture stomatitis (stomatitis subprothetica) was the object of this study. METHODS: The indirect immunofluorescence technique (IFA) utilizing CIP 628 (serotype A) Candida albicans blastospores was employed. Anti-human goat and rabbit fluorescein isothiocyanate labeled serum was used. Serial serum dilutions from 1:20 to 1:1280 and saliva serial dilutions from 1:1 to 1:8 were prepared. Specimens were read using an ML-2 fluorescence microscope. Alternative analysis, analysis of variance and graphical analysis was used for statistical analysis of data. RESULTS: Anti-Candida antibodies (mainly IgG class) were detectable at dilutions of 1:40, 1:80 and 1:160 in the serum of patients with denture stomatitis compared with healthy controls. The saliva samples of these patients showed higher titers of anti-Candida antibodies compared with controls (1:8 for IgG and 1:4 for IgA). CONCLUSIONS: IgG anti-bodies were prevalent in the saliva of our patients and they were of diagnostic value. The IgA titers did not remain constant and could be a determinant of the disease course. Each patient showed an individual serologic profile. For this reason individualized interpretation of saliva antibodies as well as a comparison with the serum anti-Candida antibodies is recommended.

Antibodies, Fungal↗