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A scoping review of active, participant centred, digital adverse events following immunization (AEFI) surveillance of WHO approved COVID-19 vaccines: A Canadian immunization Research Network study. Hum Vaccin Immunother 2024; 20:2293550. [PMID: 38374618 PMCID: PMC10880498 DOI: 10.1080/21645515.2023.2293550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 12/08/2023] [Indexed: 02/21/2024] Open
Abstract
This scoping review examines the role of digital solutions in active, participant-centered surveillance of adverse events following initial release of COVID-19 vaccines. The goals of this paper were to examine the existing literature surrounding digital solutions and technology used for active, participant centered, AEFI surveillance of novel COVID-19 vaccines approved by WHO. This paper also aimed to identify gaps in literature surrounding digital, active, participant centered AEFI surveillance systems and to identify and describe the core components of active, participant centered, digital surveillance systems being used for post-market AEFI surveillance of WHO approved COVID-19 vaccines, with a focus on the digital solutions and technology being used, the type of AEFI detected, and the populations under surveillance. The findings highlight the need for customized surveillance systems based on local contexts and the lessons learned to improve future vaccine monitoring and pandemic preparedness.
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Safety of influenza vaccination during pregnancy: a systematic review. BMJ Open 2023; 13:e066182. [PMID: 37673449 PMCID: PMC10496691 DOI: 10.1136/bmjopen-2022-066182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/18/2023] [Indexed: 09/08/2023] Open
Abstract
OBJECTIVE We conducted a systematic review to evaluate associations between influenza vaccination during pregnancy and adverse birth outcomes and maternal non-obstetric serious adverse events (SAEs), taking into consideration confounding and temporal biases. METHODS Electronic databases (Ovid MEDLINE ALL, Embase Classic+Embase and the Cochrane Central Register of Controlled Trials) were searched to June 2021 for observational studies assessing associations between influenza vaccination during pregnancy and maternal non-obstetric SAEs and adverse birth outcomes, including preterm birth, spontaneous abortion, stillbirth, small-for-gestational-age birth and congenital anomalies. Studies of live attenuated vaccines, single-arm cohort studies and abstract-only publications were excluded. Records were screened using a liberal accelerated approach initially, followed by a dual independent approach for full-text screening, data extraction and risk of bias assessment. Pairwise meta-analyses were conducted, where two or more studies met methodological criteria for inclusion. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to assess evidence certainty. RESULTS Of 9443 records screened, 63 studies were included. Twenty-nine studies (24 cohort and 5 case-control) evaluated seasonal influenza vaccination (trivalent and/or quadrivalent) versus no vaccination and were the focus of our prioritised syntheses; 34 studies of pandemic vaccines (2009 A/H1N1 and others), combinations of pandemic and seasonal vaccines, and seasonal versus seasonal vaccines were also reviewed. Control for confounding and temporal biases was inconsistent across studies, limiting pooling of data. Meta-analyses for preterm birth, spontaneous abortion and small-for-gestational-age birth demonstrated no significant associations with seasonal influenza vaccination. Immortal time bias was observed in a sensitivity analysis of meta-analysing risk-based preterm birth data. In descriptive summaries for stillbirth, congenital anomalies and maternal non-obstetric SAEs, no significant association with increased risk was found in any studies. All evidence was of very low certainty. CONCLUSIONS Evidence of very low certainty suggests that seasonal influenza vaccination during pregnancy is not associated with adverse birth outcomes or maternal non-obstetric SAEs. Appropriate control of confounding and temporal biases in future studies would improve the evidence base.
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A214 WOMEN WITH INFLAMMATORY BOWEL DISEASE HAVE INCREASED HEALTH-CARE UTILIZATION DURING PREGNANCY AND POSTPARTUM COMPARED TO THOSE WITHOUT INFLAMMATORY BOWEL DISEASE: A POPULATION-BASED COHORT STUDY. J Can Assoc Gastroenterol 2023. [PMCID: PMC9991121 DOI: 10.1093/jcag/gwac036.214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
Background Compared to those without inflammatory bowel disease (IBD), women with IBD may have increased health-care utilization during pregnancy and postpartum. This may lead to significant morbidity and decrease in quality of life. Characterizing this health-care use is important for health-policy purposes to determine methods to shift care to the ambulatory setting. Purpose We aimed to compare health-care utilization of women with and without IBD during preconception, pregnancy and postpartum. Method We accessed administrative databases and validated algorithms at the Institute of Clinical Evaluative Services (ICES) in Ontario to identify women (age 18-55) with and without IBD who had a completed live, singleton pregnancy between 2003 and 2018. The primary outcome was to characterize differences in emergency department (ED) visits and hospitalizations between women with and without IBD during the 12 months preconception, pregnancy, and in the 12 months postpartum. The secondary outcome was to assess differences in prenatal care between women with and without IBD. Multivariable negative binomial regression with generalizing estimating equations, accounting for multiple pregnancies for each patient, was performed to report incidence rate ratios (IRR) with 95% confidence intervals (95% CI). Covariates included maternal age at conception, location of residence at conception (rural vs. urban), socioeconomic status (using surrogate marker of neighborhood income quintile), and maternal comorbidity. Result(s) 9158 pregnancies in 6163 women with IBD and 1,729,411 pregnancies in 1,091,013 women without IBD were included. Women with IBD were older at time of delivery and had greater pre-pregnancy comorbidities. During pregnancy, women with IBD were more likely to visit the ED (IRR 1.13, 95% CI,1.08-1.18) and be hospitalized (IRR 1.11, 95% CI,1.01-1.21) for non-IBD specific reasons. Similarly, during postpartum, women with IBD were more likely to visit the ED (IRR 1.21, 95% CI, 1.15-1.27) and be hospitalized (IRR 1.18, 95% CI, 1.05-1.32) for non-IBD specific reasons. Venous thromboembolic events accounted for 7.0% of all postpartum hospitalizations in women with IBD compared to 2.7% in those without IBD (p<0.0001). There was no difference in ED visits and hospitalizations between women with and without IBD in preconception. Finally, women with IBD had greater number of prenatal visits with obstetricians during pregnancy and were more likely to receive a first trimester prenatal visit compared to those without IBD. Conclusion(s) Compared to those without IBD, women with IBD are more likely to visit the ED and be hospitalized during pregnancy and postpartum, particularly for venous thromboembolic events. Efforts should be made from a health policy perspective to increase access to ambulatory care for patients with IBD during the peripartum period which in turn may reduce acute setting health-services utilization. Please acknowledge all funding agencies by checking the applicable boxes below CCC Disclosure of Interest None Declared
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Assessing Maternal and Fetal SARS-COV-2 Viral Load, Antibody Profiles and Placental Pathology Following Prenatal Infection. Am J Obstet Gynecol 2023. [DOI: 10.1016/j.ajog.2022.11.247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Peripartum Outcomes Following COVID-19 Vaccination in Late Pregnancy: Findings from a Population-Based Retrospective Cohort Study in Ontario, Canada. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2022. [PMCID: PMC9098320 DOI: 10.1016/j.jogc.2022.02.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Attention Deficit Hyperactivity Disorder in Children Born to Patients with Infertility: A Population-Based Cohort Study. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2022. [DOI: 10.1016/j.jogc.2022.02.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Universal SARS-CoV-2 Screening Among Obstetric Patients in Ottawa, Canada. Am J Obstet Gynecol 2022. [PMCID: PMC8789388 DOI: 10.1016/j.ajog.2021.11.1313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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312Long-term survival of women diagnosed with cancer during pregnancy or postpartum. Int J Epidemiol 2021. [DOI: 10.1093/ije/dyab168.106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Cancer is the second leading cause of death in reproductive-aged women, and the incidence of pregnancy-associated cancer is rising. We assessed long-term survival of women diagnosed with cancer during pregnancy or postpartum.
Methods
A population-based retrospective cohort study included all reproductive-aged women (18-50 years) with a cancer diagnosis in Alberta, Canada, 2004 to 2016. Hazard ratios (HR) were calculated for all-cause and cancer-specific mortality, comparing 244 women who were diagnosed with cancer during pregnancy and 670 women diagnosed with cancer within one year postpartum, with 3,680 women diagnosed with cancer outside of these periods as the referent. Cox regression adjusted for age at cancer diagnosis, parity, cancer stage, and type of cancer.
Results
Rates of cancer in pregnancy and postpartum did not increase across the study period (trend p-value=0.49). Women diagnosed with cancer in pregnancy had an adjusted HR of 1.61 (95% CI 1.07-2.41) for all-cause mortality, 1.67 (95% CI 1.09-2.57) for cancer-specific mortality, relative to the referent. Those diagnosed with cancer postpartum did not have a greater risk of all-cause (HR = 1.10, 95% CI 0.80-1.50) or cancer-specific (HR = 1.15, 95% CI 0.82-1.60) mortality.
Conclusions
The risk of all-cause and cancer-specific mortality is increased in women diagnosed with cancer during pregnancy.
Key messages
Women diagnosed with cancer during pregnancy experience poorer survival than those diagnosed in postpartum or remote from a pregnancy. These findings should be used by physicians to guide care of women diagnosed with pregnancy-associated cancers.
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A Retrospective Cohort Study Investigating the Impact of Maternal Pre-Pregnancy Body Mass Index on Pediatric Health Service Utilization. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2021; 43:1267-1273. [PMID: 34029752 DOI: 10.1016/j.jogc.2021.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Maternal weight during pregnancy impacts the health of both mother and baby. This project investigated associations between maternal pre-pregnancy body mass index (BMI) and the child's future health service utilization. METHODS The study population comprised all women who delivered a singleton, live infant in Ontario between 2012 and 2014, and was assembled from data contained in the provincial birth registry. Health service utilization in the 24 months following birth was examined by linking data from the registry with other provincial health administrative databases housed at ICES. RESULTS A total of 258 005 records were available for analysis. After adjusting for infant sex and maternal age, smoking status, income quintile, and pre-existing or gestational diabetes or hypertension, children born to mothers who were overweight or had obesity prior to pregnancy had increased rates of hospitalization (overweight adjusted incidence rate ratio [aIRR] 1.09, 95% confidence interval [CI] 1.06-1.12; obesity aIRR 1.20, 95% CI 1.17-1.24), physician visits (overweight aIRR 1.03, 95% CI 1.03-1.04; obesity aIRR 1.05, 95% CI 1.04-1.05) and emergency department visits (overweight aIRR 1.12, 95% CI 1.10-1.13; obesity aIRR 1.27, 95% CI 1.25-1.29) than infants born to mothers with normal pre-pregnancy BMI. CONCLUSION Excess maternal weight was associated with greater pediatric health service utilization. Rates of health service utilization appeared to increase with maternal pre-pregnancy BMI. Future study of the reasons behind this increase may allow for early education, diagnosis, and intervention in this at-risk population.
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Vaccination during pregnancy: Canadian maternity care providers' opinions and practices. Hum Vaccin Immunother 2020; 16:2789-2799. [PMID: 32271655 DOI: 10.1080/21645515.2020.1735225] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A number of countries have implemented vaccination in pregnancy as a strategy to reduce the burden of influenza and pertussis. The aim of this study was to assess the involvement of Canadian maternity care providers in administration of vaccines to their pregnant patients. A cross-sectional web-based survey was sent to family physicians, obstetricians-gynecologists, midwives, pharmacists, and nurses. A multivariable logistic regression model was used to determine variables independently associated with offering vaccination services in pregnancy in providers' practice. A total of 1,135 participants participated. Overall, 64% (n = 724) of the participants reported offering vaccines in their practice and 56% (n = 632) reported offering vaccines to pregnant patients. The main reasons reported for not offering vaccination services in pregnancy were the belief that vaccination was outside of the scope of practice; logistical issues around access to vaccines; or lack of staff to administer vaccines. In multivariable analysis, the main factors associated with vaccination of pregnant patients in practices where vaccination services were offered were: providers' confidence in counseling pregnant patients about vaccines, seeing fewer than 11 pregnant patients on average each week, and being a nurse or a family physician. Although the majority of participants expressed strong support for vaccination during pregnancy, half were not offering vaccination services in their practice. Many were not equipped to offer vaccines in their practice or felt that it was not their role to do so. To enhance vaccine acceptance and uptake in pregnancy, it will be important to address the logistical barriers identified in this study.
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Vaccination Against Influenza in Pregnancy: A Survey of Canadian Maternity Care Providers. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2018; 41:479-488. [PMID: 30409569 DOI: 10.1016/j.jogc.2018.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/06/2018] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Influenza vaccine uptake among Canadian pregnant individuals is suboptimal. Failure to incorporate vaccination into routine prenatal care and a lack of recommendations from healthcare providers are recognized as barriers to vaccination. The aim of this study was to assess Canadian maternity care providers' knowledge, attitudes, and practices regarding influenza vaccination in pregnancy. METHODS A cross-sectional Web-based questionnaire was sent during July and August 2017 to family physicians, obstetricians-gynaecologists, midwives, pharmacists, and nurses who care for pregnant individuals. A multivariable logistic regression model was used to determine variables independently associated with providers' recommendation of the influenza vaccine in pregnancy. RESULTS The analysis included 1061 providers. Most participants (85%) reported being vaccinated against influenza themselves, and 72% reported recommending the influenza vaccine to all of their pregnant patients during the previous influenza season. Participants' attitudes regarding influenza vaccination during pregnancy were generally positive: 64% strongly agreed that pregnant individuals are at an increased risk of complications from influenza, and 69% strongly agreed that it is safe to vaccinate pregnant individuals against influenza. The main determinants of participants' recommendations for influenza vaccination to all pregnant patients were following official recommendations on influenza vaccination, discussing vaccines with most or all pregnant individuals seen in their practice, and being vaccinated themselves during the previous influenza season. CONCLUSION Enhancing influenza vaccine uptake in pregnancy is largely dependent on maternity care providers' recommendations. This study provides valuable insight on providers' knowledge, attitudes, and practices.
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Prenatal exposure to the 2009 pandemic H1N1 influenza vaccine on health outcomes in children. Int J Popul Data Sci 2018. [DOI: 10.23889/ijpds.v3i4.856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
IntroductionDuring the 2009 H1N1 pandemic, less than half of pregnant women in Ontario received the recommended influenza vaccine. Commonly-cited reasons for low vaccine uptake include misconceptions about the possible impact of maternal influenza infection and vaccine safety. Providing data on previously understudied pediatric health outcomes may help increase vaccine uptake.
Objectives and ApproachWe conducted a retrospective cohort study of all live births from November 2nd, 2009 to October 31st, 2010 using the BORN Ontario province-wide birth registry containing information on H1N1 vaccination. These data were deterministically/probabilistically linked with several health administrative databases held at the Institute for Clinical Evaluative Sciences to ascertain specific immune-related pediatric health outcomes and health services utilization over 5 years of follow-up. Negative binomial regression models were used to evaluate the association between prenatal H1N1 vaccination and outcomes. Stabilized inverse probability of treatment weights (sIPTW) derived from the propensity scores were used to adjust for potential confounding.
ResultsThe study cohort included 104,310 eligible infants, 31,310 (30%) of whom were born to H1N1-vaccinated women. Median follow-up time was 5 years. Using sIPTWs we were able to achieve good balance of baseline measured covariates across exposure groups, with no absolute standardized differences larger than 7%. The sIPTW-adjusted analyses indicated no significant associations between prenatal exposure to H1N1 vaccination and upper respiratory infections (adjusted rate ratio [aRR] 1.01; 95% confidence interval [CI] 0.98-1.03), lower respiratory infections (aRR 1.00; 95%CI 0.96-1.04), otitis media (aRR 1.04; 95%CI 1.00-1.07), all infections (aRR 1.00; 95%CI 0.98-1.03), and rates of urgent and in-patient health services utilization (aRR 1.00; 95%CI 0.98-1.02).
Conclusion/ImplicationsOur primary findings suggest there are no associations between prenatal exposure to H1N1 vaccination and (1) the development of several immune-related health outcomes in children; (2) rates of health services utilization. Furthermore, our study provides new evidence on the long-term safety of influenza vaccination during pregnancy, which is currently lacking.
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Severe maternal morbidity after IVF in overweight or obese women. Fertil Steril 2017. [DOI: 10.1016/j.fertnstert.2017.07.311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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A mixed methods evaluation of the maternal-newborn dashboard in Ontario: dashboard attributes, contextual factors, and facilitators and barriers to use: a study protocol. Implement Sci 2016; 11:59. [PMID: 27142655 PMCID: PMC4855363 DOI: 10.1186/s13012-016-0427-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 04/26/2016] [Indexed: 11/30/2022] Open
Abstract
Background There are wide variations in maternal-newborn care practices and outcomes across Ontario. To help institutions and care providers learn about their own performance, the Better Outcomes Registry & Network (BORN) Ontario has implemented an audit and feedback system, the Maternal-Newborn Dashboard (MND), for all hospitals providing maternal-newborn care. The dashboard provides (1) near real-time feedback, with site-specific and peer comparison data about six key performance indicators; (2) a visual display of evidence-practice gaps related to the indicators; and (3) benchmarks to provide direction for practice change. This study aims to evaluate the effects of the dashboard, dashboard attributes, contextual factors, and facilitation/support needs that influence the use of this audit and feedback system to improve performance. The objectives of this study are to (1) evaluate the effect of implementing the dashboard across Ontario; (2) explore factors that potentially explain differences in the use of the MND among hospitals; (3) measure factors potentially associated with differential effectiveness of the MND; and (4) identify factors that predict differences in hospital performance. Methods/design A mixed methods design includes (1) an interrupted time series analysis to evaluate the effect of the intervention on six indicators, (2) key informant interviews with a purposeful sample of directors/managers from up to 20 maternal-newborn care hospitals to explore factors that influence the use of the dashboard, (3) a provincial survey of obstetrical directors/managers from all maternal-newborn hospitals in the province to measure factors that influence the use of the dashboard, and (4) a multivariable generalized linear mixed effects regression analysis of the indicators at each hospital to quantitatively evaluate the change in practice following implementation of the dashboard and to identify factors most predictive of use. Discussion Study results will provide essential data to develop knowledge translation strategies for facilitating practice change, which can be further evaluated through a future cluster randomized trial.
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Ankle position during strength training does influence isokinetic knee extensor and flexor strength gains. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.3616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Building a pan-Canadian practice-based research network for inherited metabolic diseases: The first two years of the Canadian Inherited Metabolic Diseases Research Network (CIMDRN). Clin Biochem 2014. [DOI: 10.1016/j.clinbiochem.2014.07.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Measuring contact angle and meniscus shape with a reflected laser beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:013703. [PMID: 24517771 DOI: 10.1063/1.4861188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Side-view imaging of the contact angle between an extended planar solid surface and a liquid is problematic. Even when aligning the view perfectly parallel to the contact line, focusing one point of the contact line is not possible. We describe a new measurement technique for determining contact angles with the reflection of a widened laser sheet on a moving contact line. We verified this new technique measuring the contact angle on a cylinder, rotating partially immersed in a liquid. A laser sheet is inclined under an angle φ to the unperturbed liquid surface and is reflected off the meniscus. Collected on a screen, the reflection image contains information to determine the contact angle. When dividing the laser sheet into an array of laser rays by placing a mesh into the beam path, the shape of the meniscus can be reconstructed from the reflection image. We verified the method by measuring the receding contact angle versus speed for aqueous cetyltrimethyl ammonium bromide solutions on a smooth hydrophobized as well as on a rough polystyrene surface.
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Factors associated with perceived stress and stressful life events in pregnant women: findings from the Canadian Maternity Experiences Survey. Matern Child Health J 2012; 16:158-68. [PMID: 21165763 DOI: 10.1007/s10995-010-0732-2] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Prenatal maternal stress has been linked to multiple adverse outcomes. Researchers have used a variety of methods to assess maternal stress. The purpose of this study was to explore and compare factors associated with stress in pregnancy as measured by perceived stress and stressful life events. We analyzed data from the Canadian Maternity Experiences Survey. A randomly selected sample of 8,542 women who had recently given birth was drawn from the 2006 Canadian Census. Women were eligible if they were at least 15 years of age, had delivered a live, singleton infant, and were living with their infant at the time of the interview (5-14 months postpartum). Prevalence estimates and odds ratios were calculated using sample weights of the survey and their variances were calculated using bootstrapping methods. Bivariate analyses identified statistically significant factors associated with each stress measure. Backward stepwise multivariate logistic regression models were constructed. A total of 6,421 women (78%) participated in the computer assisted telephone interview. Twelve percent of women experienced high levels of perceived stress and 17.1% reported having three or more stressful life events in the year prior to the birth of their baby. In the final model, psychosocial variables were associated with both outcomes, whereas demographic factors were associated only with life event stress. Different factors contributed to perceived stress and life event stress, suggesting that these concepts measure different aspects of stress. These findings can inform routine psychosocial risk assessment in pregnancy.
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The effect of maternal Class III obesity on neonatal outcomes: a retrospective matched cohort study. J Matern Fetal Neonatal Med 2012; 25:2281-6. [DOI: 10.3109/14767058.2012.688080] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
BACKGROUND AND OBJECTIVE Pregnant adolescents face unique challenges. Understanding the experiences, knowledge, and behaviors of adolescents during the pregnancy and postpartum periods may contribute to improvement of their maternity care. The purpose of this study was to compare the maternity experiences, knowledge, and behaviors of adolescent, young adult, and adult women by using a nationally representative sample. METHODS This study used data from the Canadian Maternity Experiences Survey (N = 6421). The weighted proportions of each variable were calculated by using survey sample weights. Logistic regression was used to estimate odds ratios. Bootstrapping techniques were used to calculate variance estimates for prevalence and 95% confidence intervals. RESULTS Adolescents and young adults were more likely to experience physical abuse in the previous 2 years, initiate prenatal care late, not take folic acid before or during pregnancy, have poor prenatal health behaviors, have a lower cesarean delivery rate, have lower breastfeeding initiation and duration rates, experience more stressful life events, experience postpartum depression symptoms, and rate their infant's health as suboptimal than adult women. Adolescents were more likely to rate their own health as suboptimal. CONCLUSIONS Adolescents have unique needs during pregnancy and postpartum. Health care professionals should seek to provide care in a manner that acknowledges these needs.
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Abstract
BACKGROUND In Canada maternity care is publicly funded, and although women may choose their care providers, choices may be limited. The purpose of this study was to compare perceptions of maternity outcomes and experiences of those who received care from midwives with those who received care from other providers. METHODS Based on the 2006 Canadian census, a random sample of women (n = 6,421) who had recently given birth in Canada completed a computer-assisted telephone interview for the Maternity Experiences Survey. The sample was stratified according to province or territory where birth occurred, age, rural or urban residence, and presence of other children in the home. Those who were 15 years of age and older, gave birth to a singleton baby, and were living with their infant were eligible for inclusion. RESULTS Women whose primary prenatal providers were midwives had fewer ultrasounds and were more likely to attend prenatal classes and have at least five or more prenatal visits. They were also more likely to rate satisfaction with their maternity experience as "very positive" and be satisfied with information provided on a variety of pregnancy and birth topics if their primary prenatal provider was a midwife. They were almost half as likely to experience induction and 7.33 times more likely to experience a medication-free delivery. They were more likely to initiate and maintain breastfeeding at 3 and 6 months. CONCLUSIONS Evidence shows that midwifery outcomes and levels of satisfaction meet or exceed Canadian maternity care standards. Facilitation of the continuing integration of midwives as autonomous practitioners throughout Canada is recommended. (BIRTH 38:3 September 2011).
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Pneumococcal and influenza immunization in asplenic persons: a retrospective population-based cohort study 1990-2002. BMC Infect Dis 2010; 10:219. [PMID: 20649965 PMCID: PMC2920873 DOI: 10.1186/1471-2334-10-219] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 07/22/2010] [Indexed: 01/19/2023] Open
Abstract
Background Splenectomy is associated with increased risk for bacteremia, due to impaired clearance of bloodborne agents and to altered phagocytosis and humoral immunity. We conducted a retrospective cohort study of patients at risk for splenectomy for a 13-year period to determine immunization coverage, and outcomes of those with and without splenectomy, and with or without receipt of influenza or pneumococcal vaccine. Methods Data were extracted from the provincial Medical Services Insurance database for insured services rendered by a physician for 1990-2002, and from the Vital Statistics Death database. The eligible cohort was selected based on diagnostic codes for hematologic conditions for which splenectomy might be considered, such as immune thrombocytopenia. Each patient was followed longitudinally from the date of first diagnosis until 31Dec2002, or death, or relocation out-of province. In addition, persons with splenectomy and no hematologic condition were identified and followed for 6 months post-surgery. Infectious illness rates per 100 person-years of observation and death rates were calculated with and without splenectomy. Death rates were determined using splenectomy status as a time-dependent covariate. The relationship between splenectomy and death according to immunization status was examined using Cox proportional hazard ratios. Results Of 38,812 persons in the cohort 427 subjects with a hematologic diagnosis had splenectomy and another 452 subjects without a hematologic diagnosis had this surgery. 72% were > 18 years of age. Pneumococcal immunization was recorded in 16.5% of asplenic patients overall, and was not associated with reduced risk of death in these persons (adjusted Hazard Ratio [HR] = 1.07, 95% CI 0.70 - 1.65). Influenza immunization was recorded in 53.1% of asplenic patients overall, and was associated with reduced risk of death (adjusted HR = 0.46, 0.33-0.62). No pneumococcal or influenza immunization was recorded in patients with a hematologic diagnosis without splenectomy. Infectious illness visits were higher among all patients who had a splenectomy than among those without a splenectomy (151 visits/100 person-years of observation in the post-splenectomy period vs. 120 visits/100 person-years; p < 0.0001). Conclusions In asplenic patients, influenza immunization is associated with a 54% reduced risk of death compared to unimmunized asplenic persons; no reduction in risk was demonstrated with (polysaccharide) pneumococcal vaccine. Vaccine coverage in the entire cohort was less than routinely recommended. Improved delivery of infection prevention programs to this population is warranted. Conjugate pneumococcal vaccines should be urgently studied in this immunocompromised population.
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A review of Aboriginal infant mortality rates in Canada: striking and persistent Aboriginal/non-Aboriginal inequities. Canadian Journal of Public Health 2010. [PMID: 20524380 DOI: 10.1007/bf03404361] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The Joint Working Group on First Nations, Indian, Inuit, and Métis Infant Mortality of the Canadian Perinatal Surveillance System is a collaboration of national Aboriginal organizations and federal and provincial/territorial stakeholders. Our objective was to better understand what is currently known about Aboriginal infant mortality rates (IMR) in Canada. METHODS As part of a larger international systematic review of Indigenous IMR calculation, we searched the published literature for original research regarding the calculation of First Nations, Inuit, and Métis infant mortality rates at the national and provincial/territorial level. SYNTHESIS We identified major deficiencies in the coverage and quality of infant mortality data for Aboriginal populations in Canada. The review of provincial and territorial reporting of infant mortality for Aboriginal populations revealed substantial provincial and territorial variation in the way that birth and death data were collected. With respect to coverage, high-quality IMRs were available only for Status Indians and communities with a high proportion of Inuit residents. No rates were available for Métis or non-Status Indians. CONCLUSION Striking and persistent disparities persist in the IMRs for Status Indians and in communities with a high proportion of Inuit residents, compared to the general Canadian population. There is an urgent need to work in partnership with First Nations, Indian, Inuit, and Métis stakeholder groups to improve the quality and coverage of Aboriginal IMR information and to acquire information that would help to better understand and address the underlying causes of disparities in infant mortality between the Aboriginal and non-Aboriginal population in Canada.
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Abstract
The following report selects and summarises some of the conclusions and recommendations generated throughout a series of workshops and discussions that have lead to the publication of the Science Policy Briefing (SPB) Nr. 35, published by the European Science Foundation. (Large parts of the present text are directly based on the ESF SPB. Detailed recommendations with regard to specific application areas are not given here but can be found in the SPB. Issues related to mathematical modelling, including training and the need for an infrastructure supporting modelling are discussed in greater detail in the present text.)The numerous reports and publications about the advances within the rapidly growing field of systems biology have led to a plethora of alternative definitions for key concepts. Here, with 'mathematical modelling' the authors refer to the modelling and simulation of subcellular, cellular and macro-scale phenomena, using primarily methods from dynamical systems theory. The aim of such models is encoding and testing hypotheses about mechanisms underlying the functioning of cells. Typical examples are models for molecular networks, where the behaviour of cells is expressed in terms of quantitative changes in the levels of transcripts and gene products. Bioinformatics provides essential complementary tools, including procedures for pattern recognition, machine learning, statistical modelling (testing for differences, searching for associations and correlations) and secondary data extracted from databases.Dynamical systems theory is the natural language to investigate complex biological systems demonstrating nonlinear spatio-temporal behaviour. However, the generation of experimental data suitable to parameterise, calibrate and validate such models is often time consuming and expensive or not even possible with the technology available today. In our report, we use the term 'computational model' when mathematical models are complemented with information generated from bioinformatics resources. Hence, 'the model' is, in reality, an integrated collection of data and models from various (possibly heterogeneous) sources. The present report focuses on a selection of topics, which were identified as appropriate case studies for medical systems biology, and adopts a particular perspective which the authors consider important. We strongly believe that mathematical modelling represents a natural language with which to integrate data at various levels and, in doing so, to provide insight into complex diseases: 1. Modelling necessitates the statement of explicit hypotheses, a process which often enhances comprehension of the biological system and can uncover critical points where understanding is lacking. 2. Simulations can reveal hidden patterns and/or counter-intuitive mechanisms in complex systems. 3. Theoretical thinking and mathematical modelling constitute powerful tools to integrate and make sense of the biological and clinical information being generated and, more importantly, to generate new hypotheses that can then be tested in the laboratory.Medical Systems Biology projects carried out recently across Europe have revealed a need for action: 4. While the need for mathematical modelling and interdisciplinary collaborations is becoming widely recognised in the biological sciences, with substantial implications for the training and research funding mechanisms within this area, the medical sciences have yet to follow this lead. 5. To achieve major breakthroughs in Medical Systems Biology, existing academic funding schemes for large-scale projects need to be reconsidered. 6. The hesitant stance of the pharmaceutical industry towards major investment in systems biology research has to be addressed. 7. Leading medical journals should be encouraged to promote mathematical modelling.
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Abstract
It is necessary to monitor autism prevalence in order to plan education support and health services for affected children. This study was conducted to assess the accuracy of administrative health databases for autism diagnoses. Three administrative health databases from the province of Nova Scotia were used to identify diagnoses of autism spectrum disorders (ASD): the Hospital Discharge Abstract Database, the Medical Services Insurance Physician Billings Database and the Mental Health Outpatient Information System database. Seven algorithms were derived from combinations of requirements for single or multiple ASD claims from one or more of the three administrative databases. Diagnoses made by the Autism Team of the IWK Health Centre, using state-of-the-art autism diagnostic schedules, were compared with each algorithm, and the sensitivity, specificity and C-statistic (i.e. a measure of the discrimination ability of the model) were calculated. The algorithm with the best test characteristics was based on one ASD code in any of the three databases (sensitivity=69.3%). Sensitivity based on an ASD code in either the hospital or the physician billing databases was 62.5%. Administrative health databases are potentially a cost efficient source for conducting autism surveillance, especially when compared to methods involving the collection of new data. However, additional data sources are needed to improve the sensitivity and accuracy of identifying autism in Canada.
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Validity of autism diagnoses using administrative health data. CHRONIC DISEASES IN CANADA 2009; 29:102-7. [PMID: 19527568 PMCID: PMC3212104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
It is necessary to monitor autism prevalence in order to plan education support and health services for affected children. This study was conducted to assess the accuracy of administrative health databases for autism diagnoses. Three administrative health databases from the province of Nova Scotia were used to identify diagnoses of autism spectrum disorders (ASD): the Hospital Discharge Abstract Database, the Medical Services Insurance Physician Billings Database and the Mental Health Outpatient Information System database. Seven algorithms were derived from combinations of requirements for single or multiple ASD claims from one or more of the three administrative databases. Diagnoses made by the Autism Team of the IWK Health Centre, using state-of-the-art autism diagnostic schedules, were compared with each algorithm, and the sensitivity, specificity and C-statistic (i.e. a measure of the discrimination ability of the model) were calculated. The algorithm with the best test characteristics was based on one ASD code in any of the three databases (sensitivity=69.3%). Sensitivity based on an ASD code in either the hospital or the physician billing databases was 62.5%. Administrative health databases are potentially a cost efficient source for conducting autism surveillance, especially when compared to methods involving the collection of new data. However, additional data sources are needed to improve the sensitivity and accuracy of identifying autism in Canada.
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Femoral nerve block after ilio-inguinial block. Anaesthesia 2007. [DOI: 10.1111/j.1365-2044.1988.tb05643.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
BACKGROUND Trihalomethanes (THMs) occurring in public drinking water sources have been investigated in several epidemiological studies of fetal death and results support a modest association. Other classes of disinfection by-products found in drinking water have not been investigated. AIMS To investigate the effects of haloacetic acid (HAA) compounds in drinking water on stillbirth risk. METHODS A population based case-control study was conducted in Nova Scotia and Eastern Ontario, Canada. Estimates of daily exposure to total and specific HAAs were based on household water samples and questionnaire information on water consumption at home and work. RESULTS The analysis included 112 stillbirth cases and 398 live birth controls. In analysis without adjustment for total THM exposure, a relative risk greater than 2 was observed for an intermediate exposure category for total HAA and dichloroacetic acid measures. After adjustment for total THM exposure, the risk estimates for intermediate exposure categories were diminished, the relative risk associated with the highest category was in the direction of a protective effect, and all confidence intervals included the null value. CONCLUSIONS No association was observed between HAA exposures and stillbirth risk after controlling for THM exposures.
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I NFLUENCE OF AN EWP ROVINCE-WIDET RAUMAS YSTEM ONM OTORV EHICLET RAUMAC ARE ANDO UTCOMES. PREHOSP EMERG CARE 2004. [DOI: 10.1080/312703003289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Pediatric Anaesthesia (4th edition). Anaesthesia 2002. [DOI: 10.1046/j.1365-2044.2002.27912.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Analgesia for circumcision in a paediatric population: comparison of caudal bupivacaine alone with bupivacaine plus two doses of clonidine. Paediatr Anaesth 2001; 11:695-700. [PMID: 11696146 DOI: 10.1046/j.1460-9592.2001.00748.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Clonidine is often used to improve the duration and quality of analgesia produced by caudal epidural blockade, although the optimum dose of clonidine with bupivacaine remains uncertain. METHODS We compared the effect of clonidine, 1 and 2 microg x kg(-1), added to bupivacaine (1.25 mg x kg(-1)) with that of bupivacaine alone in 75 male children undergoing elective circumcision. RESULTS There was a trend towards increasing duration of analgesia with increasing dose of clonidine [group B (bupivacaine) 280.7 (171.6) min, C1 (bupivacaine + clonidine 1 microg x kg(-1)) 327.8 (188.3) min and C2 (bupivacaine + clonidine 2 microg x kg(-1)) 382.0 (200.6) min], although this difference was not statistically significant. Mean time to arousal from anaesthesia was significantly prolonged with clonidine 2 microg kg(-1) (group C2 21.3 (13-36) min, group C1 14.0 (6-25) min and group B 14.4 (2-32) min. Supplementary analgesic requirements and incidence of adverse effects were low, with no differences between the groups. CONCLUSIONS For paediatric circumcision, under general anaesthesia, the addition of clonidine 2 microg x kg(-1) to low volume (0.5 ml x kg(-1)) caudal anaesthetics has a limited clinical benefit for children undergoing circumcision.
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25 marketing assumptions for new economy health care leaders. MARKETING HEALTH SERVICES 2001; 21:20-3. [PMID: 11406900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Hospitals and the Web: a maturing relationship. MARKETING HEALTH SERVICES 2001; 21:36-8. [PMID: 11406904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Impact and inequity of inpatient waiting times for advanced cardiovascular services in community hospitals across the greater Toronto area. Can J Cardiol 1999; 15:777-82. [PMID: 10411616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
OBJECTIVE To assess waiting times for inpatients requiring urgent transfer for advanced cardiovascular procedures from community hospitals; the magnitude of adverse events while waiting; and possible inequity among community hospitals in access to these services. SETTING Seven representative community hospitals in the Greater Toronto Area (GTA). DESIGN Prospective data collection over 12 months (May 1997 to April 1998). PATIENTS One thousand, two hundred and three inpatients who waited a total of 7261 hospital days for advanced cardiovascular procedures. MAIN RESULTS The average (+/- SD) inpatient waiting time, in days, for catheterization was 5.7+/-1.3, angioplasty 5.8+/-2.1, bypass surgery 7.0+/-2.1 and pacemakers 4.2+/-1.6. During this time there were 14 deaths (1.2%) and 12 (1.0%) morbid events in-hospital. Extrapolation of these data to all 21 community hospitals in the GTA suggests that annually 21,783 bed days are used by inpatients awaiting transfer for advanced cardiovascular procedures, during which time 42 fatal and 36 morbid events can be expected to occur. Of the seven hospitals, one had a catheterization laboratory (group 1), two had no laboratory but had catheterizing cardiologists (group 2), and four had no laboratory and no catheterizing cardiologists (group 3). None of these hospitals had on-site revascularization facilities. The average number of days spent waiting for catheterization in group 1 (3.1+/-0.4) was significantly less than that in group 2 (5. 4+/-1.3, P<0.001) and group 3 (6.5+/-1.3, P<0.0001). The catheterization wait in group 2 was significantly less than that in group 3 (P<0.02). There were no significant differences among the three groups in the number of days spent waiting for angioplasty or bypass surgery. CONCLUSION Waiting times for inpatients requiring advanced cardiovascular procedures in GTA community hospitals are long, and are associated with substantial morbidity and mortality. These waiting times also promote inefficient bed use and increased health care costs. Furthermore, these data suggest that access to inpatient coronary angiography in the GTA is inequitable and appears to depend more on the presence of on-site catheterization laboratories or catheterizing cardiologists than on illness severity.
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Hospital marketing and the Internet: revisited. MARKETING HEALTH SERVICES 1999; 18:44-7. [PMID: 10339086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
In 1995 a study was conducted to explore the use of the Internet in hospital marketing. Use of the Internet has exploded since that study was published. This manuscript replicates the 1995 study and extends it by investigating several managerial and operational issues concerning the use of the Internet in hospital marketing.
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Marketing's role in hospital Web site development. MARKETING HEALTH SERVICES 1999; 18:42-3. [PMID: 10180335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Customer centered health care: why managed care organizations must capitalize on new technology to build brands and customer loyalty. MANAGED CARE QUARTERLY 1999; 6:9-20. [PMID: 10181710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Now, more than ever, health care organizations are desperately trying to reach out to customers and establish stronger relationships that will generate increased loyalty and repeat business. As technology, like the Internet and related mediums, allow us to do a better job of managing information and communication, health care executives must invest the time and resources necessary to bring these new advances into the day-to-day operations of their businesses. Those that do will have a head start in building their brand and their customer loyalty.
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Building Web sites that attract visitors. MARKETING HEALTH SERVICES 1999; 18:44-5. [PMID: 10179396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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The use of filters in anaesthetic breathing systems. Anaesthesia 1998; 53:407. [PMID: 9613315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Health care marketing and the Internet. MARKETING HEALTH SERVICES 1998; 17:50-1. [PMID: 10173911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Hospital marketing and the Internet. JOURNAL OF HEALTH CARE MARKETING 1997; 16:47-8. [PMID: 10169080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Digital assistance for the anaesthetist. Anaesthesia 1997; 52:610-1. [PMID: 9203904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Charge density study with the Maximum Entropy Method on model data of silicon. A search for non-nuclear attractors. CAN J CHEM 1996. [DOI: 10.1139/v96-118] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In 1990 Sakata and Sato applied the maximum entropy method (MEM) to a set of structure factors measured earlier by Saka and Kato with the Pendellösung method. They found the presence of non-nuclear attractors, i.e., maxima in the density between two bonded atoms. We applied the MEM to a limited set of Fourier data calculated from a known electron density distribution (EDD) of silicon. The EDD of silicon was calculated with the program ADF-BAND. This program performs electronic structure calculations, including periodicity, based on the density functional theory of Hohenberg and Kohn. No non-nuclear attractor between two bonded silicon atoms was observed in this density. Structure factors were calculated from this density and the same set of structure factors that was measured by Saka and Kato was used in the MEM analysis. The EDD obtained with the MEM shows the same non-nuclear attractors that were later obtained by Sakata and Sato. This means that the non-nuclear attractors in silicon are really an artefact of the MEM. Key words: Maximum Entropy Method, non-nuclear attractors, charge density. X-ray diffraction.
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Marketing on the Internet. Innovative providers educate, inform, and communicate through cyberspace. JOURNAL OF HEALTH CARE MARKETING 1995; 15:12-5. [PMID: 10154638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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BOOK REVIEWS. Br J Anaesth 1995. [DOI: 10.1093/bja/74.3.356-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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BOOK REVIEWS. Br J Anaesth 1994. [DOI: 10.1093/bja/73.6.870-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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BOOK REVIEWS. Br J Anaesth 1994. [DOI: 10.1093/bja/73.1.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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BOOK REVIEWS. Br J Anaesth 1994. [DOI: 10.1093/bja/72.5.613-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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