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PubMed2006

Temporal relationship between increased nuchal translucency and enlarged jugular lymphatic sac.

OBJECTIVE: To study the relationship between the volume of the jugular lymphatic sacs and nuchal translucency thickness in fetuses with increased nuchal translucency with advancing gestation. METHODS: Seventy-four fetuses with a nuchal translucency greater than the 95th percentile were examined weekly between 11 and 17 weeks of gestational age. The fetal neck region was studied by ultrasonography, followed by measurement of nuchal translucency and jugular lymphatic sacs. The measurements were analyzed using multilevel analysis. In case of termination of pregnancy postmortem examination was performed. RESULTS: In 40 euploid fetuses and 34 aneuploid fetuses, 159 measurements of jugular lymphatic sac volume and nuchal translucency thickness were analyzed. The volume of the jugular lymphatic sacs and gestational age showed a quadratic relation, which differed between euploid and aneuploid fetuses (P < .01). The maximum volumes were larger and present longer in fetuses with aneuploidy than in euploid fetuses (P < .01). In case of a cardiac anomaly, jugular lymphatic sac volume was larger than in cardiac normal fetuses (nonsignificant). Furthermore, the development of jugular lymphatic sac volume and increased nuchal translucency were related, whereby an increase of the nuchal translucency preceded enlargement of the jugular lymphatic sacs (P < .001). In each fetus an increase in jugular lymphatic sac volume was followed by a decrease with advancing gestation. The gestational age at maximum jugular lymphatic sac volume differed between fetuses, indicating a fetus-specific pattern. Nuchal translucency development showed a similar pattern. Postmortem examination confirmed distension of the jugular lymphatic sacs in all cases. CONCLUSION: Increased nuchal translucency is associated with abnormal lymphatic development, in which nuchal translucency enlargement precedes enlargement of jugular lymphatic sacs on ultrasound examination. Aneuploid fetuses have a more disturbed lymph angiogenesis. LEVEL OF EVIDENCE: III.

Abortion, Eugenic↗
PubMed2005

Impulsivity and decision making.

The purpose of the present study was to explore the links among the four facets of impulsivity (urgency, lack of premeditation, lack of perseverance, and sensation seeking) proposed by and decision-making processes. Thirty undergraduate students completed a self-report questionnaire evaluating impulsivity as well as a task measuring decision-making processes, the Iowa Gambling Task. Zero-order correlations and multilevel analysis revealed that only lack of premeditation was specifically linked to disadvantageous decisions on the Gambling Task. This suggests that premeditation is related to decision making influenced by somatic (or emotional) markers.

Adult↗
PubMed2005

Multilevel modelling of hospitalisations for recurrent diarrhoeal disease in Aboriginal and non-Aboriginal infants and young children in Western Australia.

A multilevel proportional hazards model was used to determine the prognostic factors affecting hospitalisations for recurrent diarrhoeal disease in infants and young children. All infants born in 1996 who had index gastroenteritis admission to Western Australian (WA) hospitals during their first year of life were included in our study cohort (n = 486). There were 618 hospital admissions for infectious diarrhoea over the 6-year follow-up period. Aboriginal children stayed significantly longer in hospital than their non-Aboriginal peers, and comorbidities such as dehydration, gastrointestinal sugar intolerance, failure to thrive, iron deficiency anaemia and certain infections (genitourinary, scabies and/or otitis media) were all significantly associated with the delayed discharge of patients. Substantial variations among patients (variance = 0.660) and between health service regions of WA (variance = 0.296) were found. Over 30% of the total variation could be attributed to the heterogeneity between health districts. For any two patients in the same health district, the within-region (intraclass) correlation was estimated to be 0.309. In the absence of detailed socio-demographic data, application of the standard survival procedure may lead to incorrect inferences due to regional clustering and repeated observations on individuals. By accounting for latent patient and regional effects, the multilevel analysis clearly confirmed the high burden of infectious diarrhoea among Aboriginal infants and children, and their much longer hospital stays. Coexisting morbidities contributed to the prolonged and recurrent hospitalisations. Findings of this epidemiological study indicated the need of multifaceted clinical disease prevention and hygiene promotion strategies to control the disease.

Anemia, Iron-Deficiency↗
PubMed2005

Self-monitoring of blood glucose in non-insulin-treated diabetic patients: a longitudinal evaluation of its impact on metabolic control.

AIMS: In the framework of a nationwide outcomes research programme, we assessed the impact of self-monitoring of blood glucose (SMBG) on metabolic control over 3 years in patients with Type 2 diabetes mellitus (DM2) not treated with insulin. METHODS: The study involved 1896 patients who completed, at 6-month intervals for 3 years, a questionnaire investigating SMBG practice. Clinical information was collected by participating clinicians at the same time intervals. The predictive value of SMBG frequency on long-term metabolic control was estimated using multilevel analysis. The impact of SMBG on metabolic control was also evaluated in distinct and homogeneous subgroups of patients showing different likelihood of performing SMBG, identified using a tree-growing technique (RECPAM). RESULTS: Overall, 22% of the patients were on diet alone and 78% were treated with oral agents; 41% practiced SMBG > or = 1/week (10.3% > or = 1/day). The analysis of metabolic control according to the frequency of SMBG failed to show any significant impact of this practice on HbA1c levels over 3 years. Similarly, changes in SMBG frequency during the study were not related to significant changes in HbA1c levels. RECPAM analysis led to the identification of eight classes, characterized by substantial differences in the likelihood of performing SMBG with a frequency of at least 1/week. Nevertheless, in none of the RECPAM classes identified, did SMBG predict a better metabolic control over 3 years of follow-up. In those RECPAM classes indicating that SMBG was mainly performed to avoid hypoglycaemic episodes, SMBG was associated with a decrease in the frequency of hypoglycaemic episodes during the study. CONCLUSIONS: In a large sample of non-insulin-treated Type 2 diabetic patients, the performance and frequency of SMBG did not predict better metabolic control over 3 years. We could not identify any specific subgroups of patients for whom SMBG practice was associated with lower HbA1c levels during the study.

Algorithms↗
PubMed2005

Octreotide is not effective in the acute treatment of migraine.

The aim of this study was to determine whether subcutaneous octreotide is effective for the treatment of acute migraine. Patients with migraine with and without aura as classified by the International Headache Society were recruited to a double-blind placebo-controlled crossover study. Patients were instructed to treat two attacks of at least moderate pain severity, with at least a 7 day interval, using subcutaneous 100 microg octreotide or matching placebo. The primary endpoint was the headache response defined as: severe or moderate pain becomes mild or nil, at 2 h. The primary endpoint was analysed using a Multilevel Analysis approach. Secondary end-points included associated symptoms and a four-point functional disability score. The study was powered to detect a 30% difference at an alpha of 0.05 and a beta of 0.8. A total of 51 patients were recruited, of whom 42 provided efficacy data on an attack treated with octreotide and 41 with placebo. Modelling the headache response as a binomial determined by treatment, using the patient as the level 2 variable, and considering a possible period effect, and sex and migraine type as other variables of interest, subcutaneous octreotide was not significantly superior to placebo. The two hour headache response rates were 20% for placebo and 14% for octreotide, whilst the two hour pain free rates were 7% and 2%, respectively. Subcutaneous octreotide 100 microg is not effective in the acute treatment of migraine when compared to placebo.

Acute Disease↗
PubMed2001

Effects of gynaecological education on interpersonal communication skills.

OBJECTIVE: To investigate the effects of an experimental communication course on how gynaecologists handle psychosocial issues in gynaecological consultation. DESIGN: Pre-post testing. Multilevel analysis was used to take into account the similarity among encounters with the same gynaecologist. SAMPLE: Eighteen gynaecologists (13 consultants and 5 junior doctors) from five different hospitals participated. All gynaecologists videotaped consecutive outpatient encounters before and after attending an intensive training course. MAIN OUTCOME MEASURES: The communicative performance of the gynaecologists at pre-and post measurement. RESULTS: The gynaecologists recorded a total of 526 outpatient encounters, 272 before and 254 after the training. As a result of the training, gynaecologists' sensitivity to psychosocial aspects of their patients increased. At post measurement, the gynaecologists gave more signs of agreement, became less directive, asked fewer medical questions and more psychosocial questions. No difference was found in the duration of the outpatient visits. With the trained gynaecologists, patients asked more questions and provided more psychosocial information. CONCLUSIONS: Junior doctors and clinically experienced gynaecologists can be taught to handle psychosocial issues without lengthening the visit.

Attitude of Health Personnel↗
PubMed2003

County-level income inequality and depression among older Americans.

OBJECTIVES: To examine (1) whether county-level income inequality is associated with depression among Americans aged 70 and older, taking into consideration county-level mean household income and individual-level socioeconomic status (SES), demographic characteristics, and physical health, and (2) whether income inequality effects are stronger among people with lower SES and physical health. DATA SOURCES: The individual-level data from the first wave of the Assets and Health Dynamics among the Oldest Old survey (1993-1994) were linked with the county-level income inequality and mean household income data from the 1990 Census. STUDY DESIGN: Multilevel analysis was conducted to examine the association between income inequality (the Gini coefficient) and depression. PRINCIPAL FINDINGS: Income inequality was significantly associated with depression among older Americans. Those living in counties with higher income inequality were more depressed, independent of their demographic characteristics, SES, and physical health. The association was stronger among those with more illnesses. CONCLUSIONS: While previous empirical research on income inequality and physical health is equivocal, evidence for income inequality effects on mental health seems to be strong.

Age Factors↗
PubMed2004

Quality of care for patients with type 2 diabetes mellitus in the Netherlands and the United States: a comparison of two quality improvement programs.

OBJECTIVE: To assess differences in diabetes care and patient outcomes by comparing two multifaceted quality improvement programs in two different countries, and to increase knowledge of effective elements of such programs. STUDY SETTING: Primary care in the ExtraMural Clinic (EMC) of the Department of General Practice of the Vrije Universiteit in Amsterdam, the Netherlands, and the Group Health Cooperative (GHC), a group-model health maintenance organization (HMO) in western Washington State in the United States. Data were collected from 1992 to 1997. STUDY DESIGN: In this observational study two diabetes cohorts in which a quality improvement program was implemented were compared. Both programs included a medical record system, clinical practice guidelines, physician educational meetings, audit, and feedback. Only the Dutch program (EMC) included guidelines on the structure of diabetes care and a recall system. Only the GHC program included educational outreach visits, formation of multidisciplinary teams, and patient self-management support. DATA COLLECTION: Included were 379 EMC patients, and 2,119 GHC patients with type 2 diabetes mellitus. Main process outcomes were: annual number of diabetes visits, and number of HbA1c and blood lipid measurements. Main patient outcomes were HbA1c and blood lipid levels. Multilevel analysis was used to adjust for dependency between repeated observations within one patient and for clustering of patients within general practices. PRINCIPAL FINDINGS: In the EMC process outcomes and glycemic control improved more than at GHC, however, GHC had better baseline measures. There were no differences between programs on blood lipid control. During follow-up, intensification of pharmacotherapy was noted at both sites. Differences noted between programs were in line with differences in diabetes guidelines. CONCLUSIONS: Following implementation of guidelines and organizational improvement efforts, change occurred primarily in the process outcomes, rather than in the patient outcomes. Although much effort was put into improving process and patient outcomes, both complex programs still showed only moderate effects.

Aged↗
PubMed2005

Cross-functional team processes and patient functional improvement.

OBJECTIVE: To test the hypothesis that higher levels of participation and functioning in cross-functional psychiatric treatment teams will be related to improved patient outcomes. DATA SOURCES/STUDY SETTING: Primary data were collected during the period 1992-1999. The study was conducted in 40 teams within units treating seriously mentally ill patients in 16 Veterans Affairs hospitals across the U.S. STUDY DESIGN: A longitudinal, multilevel analysis assessed the relationship between individual- and team-level variables and patients' ability to perform activities of daily living (ADL) over time. Team data were collected in 1992, 1994, and 1995. The number of times patient data were collected was dependent on the length of time the patient was treated and varied from 1 to 14 between 1992 and 1999. Key variables included: patients' ADL scores (the dependent variable); measures of team participation and team functioning; the number of days from baseline on which a patient's ADLs were assessed; and several control variables. DATA COLLECTION METHODS: Team data were obtained via self-administered questionnaires distributed to staff on the study teams. Additional team data were obtained via questionnaires completed by unit directors contemporaneously with the staff survey. Patient data were collected by trained clinicians at regular intervals using a standard assessment instrument. PRINCIPAL FINDINGS: Results indicated that patients treated in teams with higher levels of staff participation experienced greater improvement in ADL over time. No differences in ADL change were noted for patients treated in teams with higher levels of team functioning. CONCLUSIONS: Findings support our premise that team process has important implications for patient outcomes. The results suggest that the level of participation by the team as a whole may be a more important process attribute, in terms of patient improvements in ADLs, than the team's smooth functioning. These findings indicate the potential appropriateness of managerial interventions to encourage member investment in team processes.

Activities of Daily Living↗
PubMed2005

Factors associated with spousal physical violence against women in Bangladesh.

Using data from a population-based survey of 2,702 women of reproductive age and from 28 in-depth interviews of abused women conducted during 2000-01, this study explores factors associated with domestic violence in urban and rural Bangladesh. Multilevel analysis revealed that in both residential areas, dowry or other demands in marriage and a history of abuse of the husband's mother by his father increased the risk of violence. Better spousal communication and husband's education beyond the tenth grade decreased the risk of violence. In the urban area, women's being younger than their husband and participating in savings and credit groups increased the risk of abuse, whereas husband's education beyond the sixth grade had a protective effect. In the rural area, women's earning an income increased the risk. These factors are important to consider when designing interventions.

Adolescent↗
PubMed2005

The relationship of individual, family, and community characteristics with physical health: an adult study in 27 rural Minnesota counties.

CONTEXT AND PURPOSE: This study; investigates associations between the proportion of farm families in rural counties and the health of rural individuals, independent of county poverty rate and individual and family socioeconomic factors. This study also examines relationships of these socioeconomic factors and prevalence of specific diseases. METHODS: Multilevel analysis of 10,485 responses to a mailed health survey in 27 nonmetropolitan Minnesota counties. FINDINGS: Individual- and family-level variables such as age, gender, lower income, and unemployment were significantly associated with adverse physical health. The percentage of farm families in counties was significantly associated with adverse physical health of adults, independent of individual and family characteristics, county poverty rate, ethnic composition, and population density.

Adult↗
PubMed1998

Structural and functional impact of the transgenic expression of cytokines in the CNS.

Cytokines are powerful mediators of biologic responses in the CNS and may contribute to cellular injury in pathophysiologic states. In order to better understand the actions of cytokines in the intact mammalian CNS, a transgenic approach was employed that targeted the expression of different cytokines to astrocytes in mice. Fusion gene constructs consisting of a GFAP expression vector into which was inserted the DNA encoding the cytokines interleukin-6 (IL-6), IL-3, or TNF-alpha were used to generate transgenic mice. Expression of the transgene-encoded cytokines in astrocytes was confirmed at both the RNA and protein levels. Transgenic mice were subject to multilevel analysis to determine the extent of structural and functional CNS alterations. Transgenic mice exhibited distinct adult-onset, chronic-progressive neurological disorders that correlated with the level and anatomic distribution of transgene-encoded cytokine expression. The principal findings were neurodegeneration and cognitive decline due to IL-6 expression, macrophage/microglial-mediated primary demyelination with motor disease resulting from IL-3 expression, and lymphocytic meningoencephalomyelitis with paralysis induced by TNF-alpha expression. These transgenic models (1) indicate that expression of cytokines per se in the intact CNS is pathogenic, with cytokine-specific neural cell injury leading to unique functional deficits; (2) recapitulate many of the structural and functional changes seen in human inflammatory neurological disorders; (3) provide a valuable tool for advancing our understanding of the CNS pathobiology of cytokines; and (4) offer a unique resource for the development and testing of therapies aimed at abrogating the harmful actions of these important mediators.

Animals↗
PubMed2004

Reproducibility of bone mineral density measurement in daily practice.

BACKGROUND: Bone mineral density (BMD) measurements are frequently performed repeatedly for each patient. Subsequent BMD measurements allow reproducibility to be assessed. OBJECTIVE: To examine the reproducibility of BMD by dual energy x ray absorptiometry (DXA) and to investigate the practical value of different measures of reproducibility in a group of postmenopausal women. METHODS: Ninety five women, mean age 59.9 years, underwent two subsequent BMD measurements of spine and hip. Reproducibility was expressed as smallest detectable difference (SDD), coefficient of variation (CV), and intraclass correlation coefficient (ICC). Sources of variation were investigated by multilevel analysis. RESULTS: The median interval between measurements was 0 days (range 0-45). The mean difference (SD) between the measurements (g/cm(2)) was -0.001 (0.02) and -0.0004 (0.02) at L1-4 and the total hip, respectively. At L1-4 and the total hip, SDD (g/cm(2)) was +/-0.05 and +/-0.04 and CV (%) was 1.92 and 1.59, respectively. The ICC at spine and hip was 0.99. CONCLUSIONS: Reproducibility in the postmenopausal women studied was good. In a repeated DXA scan a BMD change exceeding 2 radical 2CV (%), the least significant change (LSC), or the SDD should be regarded as significant. Use of the SDD is preferable to use of the CV and LSC (%) because of its independence from BMD and its expression in absolute units. Expressed as SDD, a BMD change of at least +/-0.05 g/cm(2) at L1-4 and +/-0.04 g/cm(2) at the total hip should be considered significant.

Absorptiometry, Photon↗
PubMed2006

The cost effectiveness of behavioural graded activity in patients with osteoarthritis of hip and/or knee.

OBJECTIVE: To evaluate whether exercise treatment based on behavioural graded activity comprising booster sessions is a cost-effective treatment for patients with osteoarthritis of the hip and/or knee compared with usual care. METHODS: An economic evaluation from a societal perspective was carried out alongside a randomised trial involving 200 patients with osteoarthritis of the hip and/or knee. Outcome measures were pain, physical functioning, self-perceived change and quality of life, assessed at baseline, 13, 39 and 65 weeks. Costs were measured using cost diaries for the entire follow-up period of 65 weeks. Cost and effect differences were estimated using multilevel analysis. Uncertainty around the cost-effectiveness ratios was estimated by bootstrapping and graphically represented on cost-effectiveness planes. RESULTS: 97 patients received behavioural graded activity, and 103 patients received usual care. At 65 weeks, no differences were found between the two groups in improvement with respect to baseline on any of the outcome measures. The mean (95% confidence interval) difference in total costs between the groups was -euro773 (-euro2360 to euro772)--that is, behavioural graded activity resulted in less cost but this difference was non-significant. As effect differences were small, a large incremental cost-effectiveness ratio of euro 51,385 per quality adjusted life year was found for graded activity versus usual care. CONCLUSIONS: This study provides no evidence that behavioural graded activity is either more effective or less costly than usual care. Yielding similar results to usual care, behavioural graded activity seems an acceptable method for treating patients with osteoarthritis of the hip and/or knee.

Cost of Illness↗
PubMed2004

Effectiveness of a multiple intervention to reduce antibiotic prescribing for respiratory tract symptoms in primary care: randomised controlled trial.

OBJECTIVES: To assess the effectiveness of a multiple intervention aimed at reducing antibiotic prescription rates for symptoms of the respiratory tract in primary care. DESIGN: Randomised controlled trial. SUBJECTS: Twelve peer review groups including 100 general practitioners with their collaborating pharmacists in the region of Utrecht, Netherlands. INTERVENTION: The intervention consisted of group education meetings, with a consensus procedure on indication for and type of antibiotics and with training in communication skills; monitoring and feedback on prescribing behaviour; group education for assistants of general practitioners and pharmacists; and education material for patients. The control group did not receive any of these elements. MAIN OUTCOME MEASURES: Antibiotic prescription rates for acute symptoms of the respiratory tract and patients' satisfaction. RESULTS: 89 general practitioners completed the study (89%). At baseline, prescription rates for antibiotics for respiratory tract symptoms did not differ between intervention and control group (27% v 29%, respectively). After nine months, the prescription rates in the intervention group fell to 23%, whereas the control group's rose to 37% (mean difference in change -12%, 95% confidence interval -18.9% to -4.0%). Multilevel analysis confirmed the results of the unadjusted analysis (intervention effect -10.7%, -20.3% to -1.0%). Patients' satisfaction was high and did not differ in the two groups at baseline or after the intervention. CONCLUSIONS: A multiple intervention reduced prescribing rates of antibiotics for respiratory tract symptoms while maintaining a high degree of satisfaction among patients. Further research should focus on the sustainability and cost effectiveness of this intervention.

Adult↗
PubMed2004

Places, people, and their physical and mental functional health.

STUDY OBJECTIVE: To investigate the impact of area of residence on functional health as represented by medical outcomes study SF-36 physical and mental component summary scores. DESIGN: Multilevel analysis of cross sectional data from the European Prospective Investigation into Cancer and Nutrition in Norfolk, UK (EPIC-Norfolk). PARTICIPANTS: A community dwelling cohort of 18399 men and women, aged 41 to 80 and resident in 162 electoral wards in Norfolk, UK. MAIN RESULTS: Significant residual variation in physical functional health was observed at the area level after controlling for important individual level socioeconomic factors (p<0.001). However, the extent of this variation was modest when compared with that at the individual level (representing 0.6% of the total). About half of this variation could be explained by area deprivation. Area deprivation was associated with impaired mental functional health but residual variation at the area level (adjusted for individual level factors) was observed only for men (0.5% of total, p = 0.02). CONCLUSIONS: Area of residence was associated with physical functional health, albeit with modest effect size. Evidence for an association between area of residence and mental functional health was weak.

Adult↗
PubMed2007

Do places affect the probability of death in Australia? A multilevel study of area-level disadvantage, individual-level socioeconomic position and all-cause mortality, 1998-2000.

BACKGROUND: In Australia, studies finding an association between area-level socioeconomic disadvantage and mortality are often based on aggregate-ecological designs which confound area-level and individual-level sources of socioeconomic variation. Area-level socioeconomic differences in mortality therefore may be an artefact of varying population compositions and not the characteristics of areas as such. OBJECTIVE: To examine the associations between area-level disadvantage and all-cause mortality before and after adjustment for within-area variation in individual-level socioeconomic position (SEP) using unlinked census and mortality-register data in a multilevel context. Setting, participants and DESIGN: The study covers the total Australian continent for the period 1998-2000 and is based on decedents aged 25-64 years (n = 43,257). The socioeconomic characteristics of statistical local areas (SLA, n = 1317) were measured using an index of relative socioeconomic disadvantage, and individual-level SEP was measured by occupation. RESULTS: Living in a disadvantaged SLA was associated with higher all-cause mortality after adjustment for within-SLA variation in occupation. Death rates were highest for blue-collar workers and lowest among white-collar employees. Cross-level interactions showed no convincing evidence that SLA disadvantage modified the extent of inequality in mortality between the occupation groups. CONCLUSIONS: Multilevel analysis can be used to examine area variation in mortality using unlinked census and mortality data, therefore making it less necessary to use aggregate-ecological designs. In Australia, area-level and individual-level socioeconomic factors make an independent contribution to the probability of premature mortality. Policies and interventions to improve population health and reduce mortality inequalities should focus on places as well as people.

Adult↗
PubMed1993

Effect of the remuneration system on the general practitioner's choice between surgery consultations and home visits.

OBJECTIVE: To assess the influence of the remuneration system, municipality, doctor, and patient characteristics on general practitioners' choices between surgery and home visits. DESIGN: Prospective registration of patient contacts during one week for 116 general practitioners (GPs). SETTING: General practice in rural areas of northern Norway. MAIN OUTCOME MEASURE: Type of GP visit (surgery v home visit). RESULTS: The estimated home visit rate was 0.14 per person per year. About 7% (range 0-39%) of consultations were home visits. Using multilevel analysis it was found that doctors paid on a "fee for service" basis tended to choose home visits more often than salaried doctors (adjusted odds ratio 1.90, 99% confidence interval 0.98, 3.69), but this was statistically significant for "scheduled" visits only (adjusted OR 4.50, 99% CI 1.67, 12.08). Patients who were older, male, and who were living in areas well served by doctors were more likely to receive home visits. CONCLUSION: In the choice between home visits and surgery consultations, doctors seem to be influenced by the nature of the remuneration when the patient's problem is not acute. Although home visiting is a function of tradition, culture, and organisational characteristics, the study indicates that financial incentives may be used to change behaviour and encourage home visiting.

Acute Disease↗