Calculating access to parks and other polygonal resources: A description of open-source methodologies

Public health studies routinely use simplistic methods to calculate proximity-based "access" to greenspace, such as by measuring distances to the geographic centroids of parks or, less frequently, to the perimeter of the park area. Although computationally efficient, these approaches oversimplify exposure measurement because parks often have specific entrance points. In this tutorial paper, we describe how researchers can instead calculate more-accurate access measures using freely available open-source methods. Specifically, we demonstrate processes for calculating "service areas" representing street-network-based buffers of access to parks within set distances and mode of transportation (e.g., 1-km walk or 20-minute drive) using OpenRouteService and QGIS software. We also introduce an advanced method involving the identification of trailheads or parking lots with OpenStreetMap data and show how large parks particularly benefit from this approach. These methods can be used globally and are applicable to analyses of a wide range of studies investigating proximity access to resources.

Machine learning-based placental clusters and their associations with adverse pregnancy outcomes

BACKGROUND

Placental abnormalities have been described in clinical convenience samples, with predominately adverse outcomes. Few studies have described placental patterns in unselected samples.

OBJECTIVE

We aimed to investigate associations between co-occurring placental features and adverse pregnancy outcomes in a prospective cohort of singletons.

METHODS

Data were from the Safe Passage study (U.S. and South Africa, 2007-2015). Before 24 weeks' gestation, participants were randomly invited to donate placental tissue at delivery for blinded, standardised pathological examination. We used hierarchical clustering to construct statistically derived groups using 60 placental features. We estimated associations between the placental clusters and select adverse pregnancy outcomes, expressed as unadjusted and adjusted risk ratios (RRs) and robust 95% confidence intervals (CI).

RESULTS

We selected a 7-cluster model. After collapsing 2 clusters to form the reference group, we labelled the resulting 6 analytic clusters according to the overarching category of their most predominant feature(s): severe maternal vascular malperfusion (n = 117), fetal vascular malperfusion (n = 222), other vascular malperfusion (n = 516), inflammation 1 (n = 269), inflammation 2 (n = 175), and normal (n = 706). Risks for all outcomes were elevated in the severe maternal vascular malperfusion cluster. For instance, in unadjusted analyses, this cluster had 12 times the risk of stillbirth (RR 12.07, 95% CI 4.20, 34.68) and an almost doubling in the risk of preterm delivery (RR 1.93, 95% CI 1.27, 2.93) compared with the normal cluster. Small infant size was more common among the abnormal clusters, with the highest unadjusted RRs observed in the fetal vascular malperfusion cluster (small for gestational age birth RR 2.99, 95% CI 2.24, 3.98, head circumference <10th percentile RR 2.86, 95% CI 1.60, 5.12). Upon adjustment for known risk factors, most RRs attenuated but remained >1.

CONCLUSION

Our study adds to the growing body of epidemiologic research, finding adverse pregnancy outcomes may occur through etiologic mechanisms involving co-occurring placental abnormalities.

Impacts of the choice of distance measurement method on estimates of access to point-based resources

BACKGROUND/OBJECTIVE

Lack of access to resources such as medical facilities and grocery stores is related to poor health outcomes and inequities, particularly in an environmental justice framework. There can be substantial differences in quantifying "access" to such resources, depending on the geospatial method used to generate distance estimates.

METHODS

We compared three methods for calculating distance to the nearest grocery store to illustrate differential access at the census block-group level in the Atlanta metropolitan area, including: Euclidean distance estimation, service areas incorporating roadways and other factors, and cost distance for every point on the map.

RESULTS

We found notable differences in access across the three estimation techniques, implying a high potential for exposure misclassification by estimation method. There was a lack of nuanced exposure in the highest- and lowest-access areas using the Euclidean distance method. We found an Intraclass Correlation Coefficient (ICC) of 0.69 (0.65, 0.73), indicating moderate agreement between estimation methods.

SIGNIFICANCE

As compared with Euclidean distance, service areas and cost distance may represent a more meaningful characterization of "access" to resources. Each method has tradeoffs in computational resources required versus potential improvement in exposure classification. Careful consideration of the method used for determining "access" will reduce subsequent misclassifications.

Cannabis and cocaine use, drinking outcomes, and quality of life in general hospital inpatients with alcohol use disorder

Background: While associations between cannabis and cocaine use, and heavy drinking and quality of life (QOL), are well-established in the general population, it is unclear whether they are present in hospital inpatients with alcohol use disorder (AUD). The aim of the study was to assess associations between cannabis and cocaine use and two outcomes [heavy drinking days (HDDs) and QOL] among hospital inpatients with AUD. Methods: Hospitalized patients with AUD and at least one past-month HDD participated in this cross-sectional study. Cannabis and cocaine use were assessed using the Alcohol, Smoking, and Substance Involvement Screening Test. HDDs were assessed using the Timeline Followback. QOL was assessed by the WHOQOL-BREF instrument. Multivariable regression models assessed associations. Results: Of 248 participants, 225 (91%) had severe AUD. There were no statistically significant associations between: recent cannabis use and HDDs [Incidence Rate Ratio (IRR) = 0.95; 95% Confidence Interval (95% CI): 0.80, 1.14], cocaine use and HDDs [IRR = 0.88; 95% CI: 0.66, 1.18], or both cannabis and cocaine use and HDDs [IRR = 0.87; 95%CI: 0.70, 1.09], as compared to use of neither cannabis nor cocaine. Use of cannabis, cocaine, and both, were not associated with QOL [(odds ratio (OR) = 0.98; 95% CI:0.55, 1.74), (OR = 0.76; 95% CI:0.30, 1.93), (OR = 1.00; 95%CI: 0.49, 2.03), respectively]. Conclusions: Among hospital inpatients with AUD, there were no significant associations between cannabis and cocaine use, heavy drinking, or QOL. Our findings raise questions regarding how drug use affects AUD and whether similar results would be found among those with milder AUD and in prospective studies.

Accelerometer-Measured, Habitual Physical Activity and Circulating Brain-Derived Neurotrophic Factor: A Cross-Sectional Study

BACKGROUND

One of the mechanisms suggested to link physical activity (PA) to favorable brain health is through stimulation of neural growth factors such as brain-derived neurotrophic factor (BDNF). Acute bouts of PA stimulate circulating BDNF levels.

OBJECTIVE

In this investigation, we assessed whether habitual, accelerometer-measured PA levels were related to circulating BDNF levels in a middle-aged cohort.

METHODS

In the Framingham Heart Study Third Generation cohort, 1,769 participants provided reliable accelerometry data and were not missing BDNF measurement and platelet counts. In a cross-sectional analysis, using multivariable regression, we related PA measures to serum BDNF levels, adjusting for age, sex, smoking status, platelet count, depression status, and accelerometer wear time.

RESULTS

Our study participants (mean age 47±9 years, 50.8% women) spent an average of 22.3 mins/day moderate-to-vigorous (MV)PA. Most PA variables (steps, MVPA, light activity, and sedentary time) were not related to BDNF levels (p > 0.05). We observed a non-linear trend, where 15-50 mins/week vigorous activity was associated with lower BDNF compared to those with 0 min vigorous activity (β= -0.049±0.024, p = 0.05), but with no significant associations at lower or higher vigorous activity levels. In smokers, MVPA was also associated with lower BDNF levels (β= -0.216±0.079, p = 0.01).

CONCLUSION

Our study reveals that circulating BDNF is not chronically elevated in individuals with higher levels of habitual PA in middle-aged adults from the community and may even be chronically suppressed with higher PA in subgroups, including current smokers. These results do not contradict previous studies demonstrating that circulating BDNF rises acutely after PA.

Time to put it out - nurse-facilitated tobacco treatment in a comprehensive cancer center

Few cancer patients receive guideline-concordant care for treatment of tobacco dependence. The purpose of this pilot trial was to obtain preliminary estimates of effectiveness of an evidence-based practice intervention on the delivery of tobacco treatment and cessation outcomes in cancer patients. We conducted a pragmatic implementation trial with a before-after design in 119 current or recently quit adult smokers with cancer who met with a clinician at a single National Cancer Institute designated comprehensive cancer center (CCC) (n = 61 pre-implementation, n = 58 post-implementation). We used a multi-component strategy based on the Chronic Care Model to implement National Comprehensive Cancer Network (NCCN) guidelines for smoking cessation. Smoking cessation counseling during the index visit was assessed by exit interview and patients were interviewed by phone to assess cessation outcomes at 3-month follow-up. Performance of cessation counseling and 7-day point prevalence abstinence (PPA) were compared across the pre- and post-implementation periods using log-logistic regression, accounting for clustering by nursing staff. More patients had received assistance in quitting at the index visit during the post-implementation period compared to the pre-implementation period (30 vs. 10%, p < .01). At 3-month follow-up, 38 and 14% of participants had discussed smoking cessation medication with a CCC healthcare professional and 57 and 27% of participants had used pharmacotherapy, respectively (p < .01 for both comparisons). Seven-day PPA at 3-month follow-up was similar in both periods, however (14 vs. 12%, respectively). A multi-component tobacco treatment intervention increased the proportion of smokers who received assistance in quitting smoking during usual cancer care but did not improve cessation outcomes.

Association of Prenatal Exposure to Maternal Drinking and Smoking With the Risk of Stillbirth

IMPORTANCE

Prenatal smoking is a known modifiable risk factor for stillbirth; however, the contribution of prenatal drinking or the combination of smoking and drinking is uncertain.

OBJECTIVE

To examine whether prenatal exposure to alcohol and tobacco cigarettes is associated with the risk of stillbirth.

DESIGN, SETTING, AND PARTICIPANTS

The Safe Passage Study was a longitudinal, prospective cohort study with data collection conducted between August 1, 2007, and January 31, 2015. Pregnant women from Cape Town, South Africa, and the Northern Plains region of the US were recruited and followed up throughout pregnancy. Data analysis was performed from November 1, 2018, to November 20, 2020.

EXPOSURE

Maternal consumption of alcohol and tobacco cigarettes in the prenatal period.

MAIN OUTCOMES AND MEASURES

The main outcomes were stillbirth, defined as fetal death at 20 or more weeks' gestation, and late stillbirth, defined as fetal death at 28 or more weeks' gestation. Self-reported alcohol and tobacco cigarette consumption was captured at the recruitment interview and up to 3 scheduled visits during pregnancy. Participants were followed up during pregnancy to obtain delivery outcome.

RESULTS

Of 11663 pregnancies (mean [SD] gestational age at enrollment, 18.6 [6.6] weeks) in 8506 women for whom the pregnancy outcome was known by 20 weeks' gestation or later and who did not terminate their pregnancies, there were 145 stillbirths (12.4 per 1000 pregnancies) and 82 late stillbirths (7.1 per 1000 pregnancies). A total of 59% of pregnancies were in women from South Africa, 59% were in multiracial women, 23% were in White women, 17% were in American Indian women, and 0.9% were in women of other races. A total of 8% were older than 35 years. In 51% of pregnancies, women reported no alcohol or tobacco cigarette exposure (risk of stillbirth, 4 per 1000 pregnancies). After the first trimester, 18% drank and smoked (risk of stillbirth, 15 per 1000 births), 9% drank only (risk of stillbirth, 10 per 1000 pregnancies), and 22% smoked only (risk of stillbirth, 8 per 1000 pregnancies). Compared with the reference group (pregnancies not prenatally exposed or without any exposure after the first trimester), the adjusted relative risk of late stillbirth was 2.78 (98.3% CI, 1.12-6.67) for pregnancies prenatally exposed to drinking and smoking, 2.22 (98.3% CI, 0.78-6.18) for pregnancies prenatally exposed to drinking only after the first trimester, and 1.60 (98.3% CI, 0.64-3.98) for pregnancies prenatally exposed to smoking only after the first trimester. The adjusted relative risk for all stillbirths was 1.75 (98.3% CI, 0.96-3.18) for dual exposure, 1.26 (98.3% CI, 0.58-2.74) for drinking only, and 1.27 (98.3% CI, 0.69-2.35) for smoking only compared with the reference group.

CONCLUSIONS AND RELEVANCE

These results suggest that combined drinking and smoking after the first trimester of pregnancy, compared with no exposure or quitting before the end of the first trimester, may be associated with a significantly increased risk of late stillbirth.

Concurrent prenatal drinking and smoking increases risk for SIDS: Safe Passage Study report

BACKGROUND

Sudden infant death syndrome (SIDS) is the leading cause of postneonatal mortality. Although the rate has plateaued, any unexpected death of an infant is a family tragedy thus finding causes and contributors to risk remains a major public health concern. The primary objective of this investigation was to determine patterns of drinking and smoking during pregnancy that increase risk of SIDS.

METHODS

The Safe Passage Study was a prospective, multi-center, observational study with 10,088 women, 11,892 pregnancies, and 12,029 fetuses, followed to 1-year post delivery. Subjects were from two sites in Cape Town, South Africa and five United States sites, including two American Indian Reservations. Group-based trajectory modeling was utilized to categorize patterns of drinking and smoking exposure during pregnancy.

FINDINGS

One-year outcome was ascertained in 94·2% infants, with 28 SIDS (2·43/1000) and 38 known causes of death (3·30/1000). The increase in relative risk for SIDS, adjusted for key demographic and clinical characteristics, was 11·79 (98·3% CI: 2·59-53·7, p < 0·001) in infants whose mothers reported both prenatal drinking and smoking beyond the first trimester, 3.95 (98·3% CI: 0·44-35·83, p = 0·14), for drinking only beyond the first trimester and 4·86 (95% CI: 0·97-24·27, p = 0·02) for smoking only beyond the first trimester as compared to those unexposed or reported quitting early in pregnancy.

INTERPRETATION

Infants prenatally exposed to both alcohol and cigarettes continuing beyond the first trimester have a substantially higher risk for SIDS compared to those unexposed, exposed to alcohol or cigarettes alone, or when mother reported quitting early in pregnancy. Given that prenatal drinking and smoking are modifiable risk factors, these results address a major global public health problem.

FUNDING

National Institute on Alcohol Abuse and Alcoholism, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and the National Institute on Deafness and Other Communication Disorders.

Accelerometer-determined physical activity and cognitive function in middle-aged and older adults from two generations of the Framingham Heart Study

INTRODUCTION

Physical activity (PA) may play a role in maintenance of cognitive function in both middle and older ages and prevention of outcomes such as dementia and Alzheimer's disease.

METHODS

Cross-sectional regression analyses were performed in Framingham Heart Study Third Generation (n = 1861) and Offspring (n = 909) cohort participants assessing the association of accelerometry-measured PA with cognitive function, adjusting for age, sex, accelerometer wear time, education, occupational status/PA, and smoking status.

RESULTS

In each cohort, achieving just 10-21.4 min/day moderate-to-vigorous PA related to better executive function (P < .02); and just 10 min/day moderate-to-vigorous PA was associated with better verbal memory in middle-aged adults in the Third Generation cohort (P = .02). In older adults of the Offspring cohort, total PA (measured in steps/day) was associated with better executive function (P < .02).

DISCUSSION

PA at levels lower than the current PA Guidelines (just 10 min/day moderate-to-vigorous PA and total PA including lower intensity PA) were associated with better cognitive function.

Abstract TMP55: Abdominal Obesity Predicts Stroke Risk in the Framingham Study

Background: Previous studies have suggested that measurements of abdominal fat, such as waist circumference or waist-to-hip ratio, more accurately predict risk of stroke than body mass index (BMI). We assessed the risk of ischemic stroke associated with BMI, waist circumference, and waist-to-hip ratio in a community sample.

Methods: We pooled Framingham Heart Study (FHS) participant data from FHS clinic examinations for the Original cohort (Exam 21, date range 1988-1992) and Offspring cohort (Exam 4, 1987-1991, and Exam 7, 1998-2001). Offspring participants who did not have stroke at the end of the first 10-year observation period could contribute data to the subsequent observation period. We included stroke-free participants 45 years of age or older who obtained measurements of BMI (kg/m 2 ) and both waist and hip circumference. Multivariable Cox proportional hazards regression models were used to separately relate BMI, waist circumference, and waist-to-hip ratio to risk of incident ischemic stroke over 10 years.

Results: We analyzed data from 6,533 observation periods (mean age of participants 62±10 years, 54% female) with mean follow up time of 9.2 ±2 years. There were 240 (3.7%) incident ischemic stroke events. Each of the three body weight measurements was associated with increased stroke risk in models that adjusted for age and sex (Table). In full models, additionally adjusting for vascular risk factors that are more frequent in obese persons, only waist-to-hip ratio predicted risk of ischemic stroke. The hazard ratio (HR) per standard deviation increase in waist-to-hip ratio was 1.18, 95% CI 1.02-1.37, p=0.030.

Conclusions: Higher waist-to-hip ratio predicted 10-year risk of ischemic stroke. Waist-to-hip ratio is a simple measure of abdominal obesity that should be used in future studies investigating weight loss interventions for stroke prevention.

The Effect of the Elapsed Time Between Blood Draw and Processing on the Recovery of Fetal Cells From Maternal Blood

OBJECTIVE

To test the hypothesis that a delay in initial fetal cell enrichment processing of maternal blood samples (defined as the time between blood draw and the initial density gradient centrifugation step) compromises the ability to recover fetal cells, we performed a randomized comparison of immediate (within 4 hours of draw) versus delayed (between 18-24 hours of draw) processing.

METHODS

Four centers participated: two centers utilized flow cytometry (FLOW), and two centers utilized magnetic-activated cell sorting (MACS) techniques. Each center collected 34 samples. The outcome was the percentage of gamma positive (gamma(+)) cells for FLOW or the number of nucleated red blood cells (NRBCs) for MACS, found in the final enriched cell population. Both outcomes reflect cell properties that are potentially fetal in origin, thus making them representative of the ability to recover fetal cells.

RESULTS

Our results did not support our hypothesis that delay in processing compromises fetal cell recovery. Instead, in MACS processing, we observed an increase in recovered NRBCs when blood sample processing was delayed compared with immediate processing. There was no significant difference in gamma(+) cells with FLOW.

CONCLUSION

Time-related changes in the density of target cells, perhaps associated with their progress towards apoptosis during the delay period, may result in increased intact fetal cells with the study methods utilized.

Register data in the evaluation and program planning of addiction treatment programs: using Sweden as an example

Data from large-scale registers is often underutilized when evaluating addiction treatment programs. Since many programs collect register data regarding clients and interventions, there is a potential to make greater use of such records for program evaluation. The purpose of this article is to discuss the value of using large-scale registers in the evaluation and program planning of addiction treatment systems and programs. Sweden is used as an example of a country where register data is both available and is starting to be used in national evaluation and program planning efforts. The article focuses on possibilities, limitations and practicalities when using large-scale register data to conduct evaluations and program planning of addiction treatment programs. Main conclusions are that using register data for evaluation provides large amounts of data at low cost, limitations associated to the use of register data may be handled statistically, register data can answer important questions in planning of addiction treatment programs, and more accurate measures are needed to account for the diversity of client populations.

Clinical sensitivity and specificity of meconium fatty acid ethyl ester, ethyl glucuronide, and ethyl sulfate for detecting maternal drinking during pregnancy

BACKGROUND

We investigated agreement between self-reported prenatal alcohol exposure (PAE) and objective meconium alcohol markers to determine the optimal meconium marker and threshold for identifying PAE.

METHODS

Meconium fatty acid ethyl esters (FAEE), ethyl glucuronide (EtG), and ethyl sulfate (EtS) were quantified by LC-MS/MS in 0.1 g meconium from infants of Safe Passage Study participants. Detailed PAE information was collected from women with a validated timeline follow-back interview. Because meconium formation begins during weeks 12-20, maternal self-reported drinking at or beyond 19 weeks was our exposure variable.

RESULTS

Of 107 women, 33 reported no alcohol consumption in pregnancy, 16 stopped drinking by week 19, and 58 drank beyond 19 weeks (including 45 third-trimester drinkers). There was moderate to substantial agreement between self-reported PAE at ≥19 weeks and meconium EtG ≥30 ng/g (κ = 0.57, 95% CI 0.41-0.73). This biomarker and associated cutoff was superior to a 7 FAEE sum ≥2 nmol/g and all other individual and combination marker cutoffs. With meconium EtG ≥30 ng/g as the gold standard condition and maternal self-report at ≥19 weeks' gestation as the test condition, 82% clinical sensitivity (95% CI 71.6-92.0) and 75% specificity (95% CI 63.2-86.8) were observed. A significant dose-concentration relationship between self-reported drinks per drinking day and meconium EtG ≥30 ng/g also was observed (all P < 0.01).

CONCLUSIONS

Maternal alcohol consumption at ≥19 weeks was better represented by meconium EtG ≥30 ng/g than currently used FAEE cutoffs.

The safe passage study: design, methods, recruitment, and follow-up approach

BACKGROUND

The Safe Passage Study is a large, prospective, multidisciplinary study designed to (1) investigate the association between prenatal alcohol exposure, sudden infant death syndrome (SIDS), and stillbirth, and (2) determine the biological basis of the spectrum of phenotypic outcomes from exposure, as modified by environmental and genetic factors that increase the risk of stillbirth, SIDS, and in surviving children, fetal alcohol spectrum disorders.

METHODS

The results provided are based on an interim assessment of 6004 women enrolled, out of the 12,000 projected, from the Northern Plains, US, and Cape Town, South Africa, areas known to be of high risk for maternal drinking during pregnancy. Research objectives, study design, and descriptive statistics, including consent, recruitment, and retention information, are provided.

RESULTS

Overall visit compliance is 87%, and includes prenatal, delivery/newborn, and postnatal contacts through 1 year post-delivery. Pregnancy outcome ascertainment is 98% prior to medical chart review; less than 2% of women withdraw. Consent for the use of DNA and placental tissue exceed 94%, and consent to participate in the autopsy portion of the study is 71%.

CONCLUSIONS

The Safe Passage Study is the first multi-site study of SIDS and stillbirth to integrate prospectively collected exposure information with multidisciplinary biological information in the same maternal and fetal/infant dyad using a common protocol. Essential components of the study design and its success are close ties to the community and rigorous systems and processes to ensure compliance with the study protocol and procedures.

Interlaboratory Comparison of Fetal Male DNA Detection from Common Maternal Plasma Samples by Real-Time PCR

Background: Analysis of fetal DNA from maternal plasma by PCR offers great potential for noninvasive prenatal genetic diagnosis. To further evaluate this potential, we developed and validated a standard protocol to determine whether fetal DNA sequences could be reproducibly amplified and measured across multiple laboratories in a common set of specimens.

Methods: Each of five participating centers in a National Institute of Child Health and Human Development consortium collected 20 mL of peripheral blood from 20 pregnant women between 10 and 20 weeks of gestation. The plasma fraction was separated according to a common protocol, divided, and frozen in five aliquots. One aliquot was shipped to each participating laboratory, where DNA was extracted according to a standard protocol. All plasma samples (n = 100) were then analyzed blindly for the presence and quantity of total DNA (GAPDH) and male fetal DNA (SRY) by real-time PCR. Genomic DNA was isolated from female and male cells at one center, quantified, and shipped to the others to serve as calibrators for GAPDH and SRY, respectively.

Results: The amplification of known quantities of DNA was consistent among all centers. The mean quantity of male DNA amplified from maternal plasma when the fetus was male ranged from 51 to 228 genome equivalents (GE)/mL. Qualitative concordance was found overall among centers. The sensitivity of the assay for detection of male DNA when the fetus was male varied from 31% to 97% among centers. Specificity was more consistent (93–100%) with only four false-positive results obtained across the entire study.

Conclusions: All centers were able to consistently amplify frozen and shipped DNA. The PCR procedure used here is reliable and reproducible. Centers that extracted and amplified more DNA per milliliter of maternal plasma had superior sensitivities of Y chromosome sequence detection. The specificity of the assay was more consistent among centers. A robust and thoroughly optimized protocol for the extraction of DNA from maternal plasma is needed to make testing of fetal DNA in maternal plasma a clinically relevant analytical tool.

Error reduction and performance improvement in the emergency department through formal teamwork training: evaluation results of the MedTeams project

OBJECTIVE

To evaluate the effectiveness of training and institutionalizing teamwork behaviors, drawn from aviation crew resource management (CRM) programs, on emergency department (ED) staff organized into caregiver teams.

STUDY SETTING

Nine teaching and community hospital EDs.

STUDY DESIGN

A prospective multicenter evaluation using a quasi-experimental, untreated control group design with one pretest and two posttests of the Emergency Team Coordination Course (ETCC). The experimental group, comprised of 684 physicians, nurses, and technicians, received the ETCC and implemented formal teamwork structures and processes. Assessments occurred prior to training, and at intervals of four and eight months after training. Three outcome constructs were evaluated: team behavior, ED performance, and attitudes and opinions. Trained observers rated ED staff team behaviors and made observations of clinical errors, a measure of ED performance. Staff and patients in the EDs completed surveys measuring attitudes and opinions.

DATA COLLECTION

Hospital EDs were the units of analysis for the seven outcome measures. Prior to aggregating data at the hospital level, scale properties of surveys and event-related observations were evaluated at the respondent or case level.

PRINCIPAL FINDINGS

A statistically significant improvement in quality of team behaviors was shown between the experimental and control groups following training (p = .012). Subjective workload was not affected by the intervention (p = .668). The clinical error rate significantly decreased from 30.9 percent to 4.4 percent in the experimental group (p = .039). In the experimental group, the ED staffs' attitudes toward teamwork increased (p = .047) and staff assessments of institutional support showed a significant increase (p = .040).

CONCLUSION

Our findings point to the effectiveness of formal teamwork training for improving team behaviors, reducing errors, and improving staff attitudes among the ETCC-trained hospitals.

Fetal gender and aneuploidy detection using fetal cells in maternal blood: analysis of NIFTY I data. National Institute of Child Health and Development Fetal Cell Isolation Study

OBJECTIVES

The National Institute of Child Health and Human Development Fetal Cell Isolation Study (NIFTY) is a prospective, multicenter clinical project to develop non-invasive methods of prenatal diagnosis. The initial objective was to assess the utility of fetal cells in the peripheral blood of pregnant women to diagnose or screen for fetal chromosome abnormalities.

METHODS

Results of fluorescence in situ hybridization (FISH) analysis on interphase nuclei of fetal cells recovered from maternal blood were compared to metaphase karyotypes of fetal cells obtained by amniocentesis or chorionic villus sampling (CVS). After the first 5 years of the study we performed a planned analysis of the data. We report here the data from 2744 fully processed pre-procedural blood samples; 1292 samples were from women carrying singleton male fetuses.

RESULTS

Target cell recovery and fetal cell detection were better using magnetic-based separation systems (MACS) than with flow-sorting (FACS). Blinded FISH assessment of samples from women carrying singleton male fetuses found at least one cell with an X and Y signal in 41.4% of cases (95% CI: 37.4%, 45.5%). The false-positive rate of gender detection was 11.1% (95% CI: 6.1,16.1%). This was higher than expected due to the use of indirectly labeled FISH probes in one center. The detection rate of finding at least one aneuploid cell in cases of fetal aneuploidy was 74.4% (95% CI: 76.0%, 99.0%), with a false-positive rate estimated to be between 0.6% and 4.1%.

CONCLUSIONS

The sensitivity of aneuploidy detection using fetal cell analysis from maternal blood is comparable to single marker prenatal serum screening, but technological advances are needed before fetal cell analysis has clinical application as part of a multiple marker method for non-invasive prenatal screening. The limitations of the present study, i.e. multiple processing protocols, are being addressed in the ongoing study.

Quantifying comorbidity in a disease-specific cohort: adaptation of the total illness burden index to prostate cancer

OBJECTIVES

Numerous studies have demonstrated the importance of comorbid illness when analyzing medical outcomes. The purpose of this study was to adapt a generic comorbidity index, the Total Illness Burden Index (TIBI), for use in men with prostate cancer, and to evaluate the usefulness of the new instrument in adjusting for the impact of comorbidity on functional outcomes in a prostate cancer cohort.

METHODS

The TIBI uses patients' self-report of symptoms and diagnoses to determine not only the presence but also the severity of comorbidities in each of 16 body system domains. To create the TIBI-P (prostate cancer modification), some domains were added and others were modified according to clinical criteria. The TIBI-P was completed by 1638 men with prostate cancer followed up longitudinally in 29 urology practices in the United States. TIBI-P scores were calculated for each patient and analyzed with scores on the SF-36 quality-of-life questionnaire and with patient report of days confined to bed.

RESULTS

After adjusting for age and income, lower SF-36 scale scores and increases in confinement to bed were associated with a greater burden of comorbid illness as measured by the TIBI-P, independent of the extent of prostate cancer. The TIBI-P explained 24% of the variance in the SF-36 physical functioning domain score.

CONCLUSIONS

The TIBI-P is a powerful measure of the impact of comorbid illness on the quality of life and functioning among patients with prostate cancer. This index may prove valuable in research on clinical and economic outcomes of prostate cancer.

Tutorial in biostatistics. An introduction to hierarchical linear modelling

Hierarchical linear models are useful for understanding relationships in hierarchical data structures, such as patients within hospitals or physicians within hospitals. In this tutorial we provide an introduction to the technique in general terms, and then specify model notation and assumptions in detail. We describe estimation techniques and hypothesis testing procedures for the three types of parameters involved in hierarchical linear models: fixed effects, covariance components, and random effects. We illustrate the application using an example from the Type II Diabetes Patient Outcomes Research Team (PORT) study and use two popular PC-based statistical computing packages, HLM/2L and SAS Proc Mixed, to perform two-level hierarchical analysis. We compare output from the two packages applied to our example data as well as to simulated data. We elaborate on model interpretation and provide guidelines for model checking.

Breast cancer care in older women: sources of information, social support, and emotional health outcomes

BACKGROUND

The authors studied older women with breast cancer and asked: 1) where do older women get information regarding breast cancer care and how helpful do they perceive each of these sources to be? and 2) what aspects of social support are associated with older women's general and breast cancer specific emotional health outcomes?

METHODS

To be eligible, women had to be at least 55 years of age and newly diagnosed with TNM Stage I or II breast cancer. Data were collected from women's surgical records and a 35-minute, computer-assisted telephone interview.

RESULTS

Nearly all women rated information that was provided by their breast cancer physicians as very or somewhat helpful. Written materials provided by breast cancer physicians also were frequently rated as very or somewhat helpful. Women's marital status, religious service attendance, ratings of their physicians' technical and interpersonal care, and perceptions of their own abilities to communicate with their physicians were significantly associated with both general and breast cancer specific emotional health outcomes (all P < 0.05).

CONCLUSIONS

Although older women obtained information regarding breast cancer from a variety of sources, they relied heavily on their physicians for information. To care most effectively for this group of patients, an increased understanding of the relation between the processes and outcomes of breast cancer care is needed Identifying older women with breast cancer at risk for poor emotional health outcomes and developing methods to enhance physician-patient communication in this setting may improve these outcomes.

Metabolic control and prevalent cardiovascular disease in non-insulin-dependent diabetes mellitus (NIDDM): The NIDDM Patient Outcome Research Team

PURPOSE

Cardiovascular disease is a major cause of morbidity and death in non-insulin-dependent diabetes mellitus (NIDDM). While hyperglycemia is clearly related to diabetic microvascular complications, it contribution to large-vessel atherosclerosis is controversial.

PATIENTS AND METHODS

We performed an analysis of the association between glycemic control and prevalent cardiovascular disease in 1,539 participants in the NIDDM Patient Outcomes Research Team study who were under usual care in a health maintenance organization. Prevalent cardiovascular disease and its risk factors were identified by self-administered questionnaire. Cardiovascular disease was defined by the presence of coronary heart disease, peripheral vascular disease, and/or cerebrovascular disease. Glycohemoglobin and lipid levels were obtained from a computerized laboratory database.

RESULTS

The mean age of participants was 63 years (range 31 to 91); 51% were women. The mean duration of NIDDM was 9 years (range < 1 to 50), 35% took insulin, and 48% took sulfonylureas. Mean glycohemoglobin was 10.6%. Sixty percent had hypertension, 16% currently smoked cigarettes, and the mean total high-density lipoprotein (HDL) cholesterol ratio was 5.7. Fifty-one percent had cardiovascular disease. Cardiovascular disease prevalence remained constant across increasing quartiles of glycohemoglobin for both men and women. In contrast, prevalent cardiovascular disease was associated with established cardiovascular disease risk factors including age (67 versus 59 years, P < 0.0001), hypertension (66% versus 54%, P < 0.0001), current cigarette smoking (17% versus 13%, P < 0.005), and total/HDL cholesterol ratio (5.9 versus 5.6, P < 0.005). Cardiovascular disease was also associated with duration of NIDDM (11 versus 8 years, P < 0.0001). In multiple logistic regression analysis controlling for established cardiovascular disease risk factors and diabetes duration and therapy, glycohemoglobin remained unassociated with cardiovascular disease.

CONCLUSIONS

Glycemic control is not associated with prevalent cardiovascular disease in this large population of individuals with NIDDM. Conventional cardiovascular disease risk factors are independently associated with cardiovascular disease and be a more promising focus for clinical intervention to reduce atherosclerotic complications in NIDDM.

The care of older persons with diabetes mellitus: families and primary care physicians

OBJECTIVES

To determine the extent to which family members participate in the day-to-day management of diabetes mellitus in older persons, and in older diabetics' medical encounters, and to identify patient and family member characteristics associated with this participation.

DESIGN

A longitudinal observational study, with baseline data being reported herein.

SETTING

Three primary care practice settings in Seattle, Washington, Boston, Massachusetts, and Indianapolis, Indiana.

PARTICIPANTS

Family members of patients 70 years of age or older participating in the Patient Outcomes Research Team (PORT) Study of type II diabetics.

MAIN OUTCOME MEASUREMENTS

The two dependent variables represent, respectively, the extent of family members' assistance with diabetes-related care and participation in older diabetics' medical encounters.

RESULTS

The 357 family members enrolled were older (mean age = 66.3 years), were mostly women (76.2%), and were usually the spouses of diabetic patients (71.3%). Between 22% and 50% of family members reported helping with various aspects of diabetes care; 35.6% of family members participated regularly in their diabetic patients' medical encounters. A multiple linear regression model relating family assistance with diabetes-related care to patient and family member characteristics included four variables: patients' physical function, and the family member's relationship to the patient, assistance with basic activities of daily living (ADLs), and understanding of diabetes management issues (all P < .05). A multiple logistic regression model relating family member participation in the medical encounter to patient and family member characteristics also included four variables: patient age and physical function, and family member assistance with instrumental activities of daily living (IADLs) and with diabetes-related care (all P < .05).

CONCLUSION

The family members studied frequently assisted older diabetics with diabetes-specific care; more than one-third were regular participants in older diabetics' medical encounters. Family member involvement in the day-to-day management of diabetes and in the medical encounter was more likely when patients were functionally disabled. Health care systems and physicians need to educate their older patients, and involved family members when patients are frail, about diabetes-related care issues and support them in their roles in the management of diabetes as well as other chronic diseases.

Sex differences in academic advancement. Results of a national study of pediatricians

BACKGROUND

Although the numbers of women in training and in entry-level academic positions in medicine have increased substantially in recent years, the proportion of women in senior faculty positions has not changed. We conducted a study to determine the contributions of background and training, academic productivity, distribution of work time, institutional support, career attitudes, and family responsibilities to sex differences in academic rank and salary among faculty members of academic pediatric departments.

METHODS

We conducted a cross-sectional survey of all salaried physicians in 126 academic departments of pediatrics in the United States in January 1992. Of the 6441 questionnaires distributed, 4285 (67 percent) were returned. The sample was representative of U.S. pediatric faculty members. Multivariate models were used to relate academic rank and salary to 16 independent variables.

RESULTS

Significantly fewer women than men achieved the rank of associate professor or higher. For both men and women, higher salaries and ranks were related to greater academic productivity (more publications and grants), more hours worked, more institutional support of research, greater overall career satisfaction, and fewer career problems. Less time spent in teaching and patient care was related to greater academic productivity for both sexes. Women in the low ranks were less academically productive and spent significantly more time in teaching and patient care than men in those ranks. Adjustment for all independent variables eliminated sex differences in academic rank but not in salary.

CONCLUSIONS

Lower rates of academic productivity, more time spent in teaching and patient care and less time spent in research, less institutional support for research, and lower rates of specialization in highly paid subspecialties contributed to the lower ranks and salaries of female faculty members.

Development and testing of a new measure of case mix for use in office practice

Case mix has been shown to be of critical importance in studies of effectiveness and quality of care using health outcomes. How these variables are defined, combined, and used to adjust or increase precision in tests for differences in health outcomes has been a source of controversy. Because existing measures were developed to adjust mortality and have marginal relevance for the adjustment of functional status outcomes, especially in ambulatory settings, the authors developed a measure of case (or patient) mix that is specifically designed to adjust functional status outcomes measured in office practice or out-of-hospital settings. This measure, developed as part of Type II Diabetes Patient Outcomes Research Team project, uses patients' reports of symptoms and conditions, as well as patients' ratings of symptom intensity to characterize total disease burden. It differs from other measures of case mix in lack of dependence on diagnoses. Separate measures were developed for each of 15 different disease categories (e.g., chronic lung disease) grouped by body system affected. Within each measure, questionnaire items were combined to rate the severity of that disease on a 1 to 4 scale, according to definitions provided by clinicians. A single, global measure was developed by aggregating the 15 measures, weighted according to the expected impact of each disease category on functional outcomes and disability. In a sample of 1,738 patients, significant relationships were observed between the global case mix measure and functional status, disability days, and service utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of various methods of collecting self-reported health outcomes data among low-income and minority patients

In a randomized trial of different data collection methods, we challenged the untested assumption that reliable data cannot be obtained from lower-income and/or minority patients by self-administered questionnaires. We tested three methods of data collection among a sample of lower-income and minority patients (n = 697) in Indianapolis at a site for the Type II Diabetes Patient Outcomes Research Team. The study included a questionnaire literacy screening instrument to assess patients' functional literacy. Based on their functional literacy, patients were randomized to one of three methods of data collection: mail-out/mail-back, hand-out/assisted, or the in-home interview. We constructed a tiered system for reassigning nonresponders to alternative methods of data collection, using the in-home interview as the fall-back strategy. We compared the response rates, item completion rates, and internal consistency reliabilities of self-reported health status measures between patients with and without literacy limitations and across the three methods of data collection. Patients with and without literacy limitations, across methods of data collection, provided high-quality data, as evidenced by high item completion rates (> 84%) and high reliability assessments (internal consistency reliability coefficients > .80) for each health status measure. As part of the tiered study design, nonresponders randomized to either the mail-out/mail-back or the hand-out/assisted method were interviewed. These patients were significantly older, had significantly lower education and income levels, and had significantly poorer self-reported visual function as compared with those who responded to the originally assigned method. We conclude that expensive, labor-intensive data collection methods, such as in-home interviews, are not necessary for many low-income, minority patients to generate high-quality, reliable health status data. Using appropriate screening instruments, those patient subgroups needing special help can be screening instruments, those patient subgroups needing special help can be identified and targeted for more expensive data collection methods. This tiered approach has policy implications for the cost, feasibility, and quality of data collection in health outcomes research.

Osteonecrosis of the humeral head in sickle cell disease

The prevalence and incidence of osteonecrosis (ON) of the humeral head in sickle cell disease was determined by a study of 2524 patients who were entered into a prospective study and followed for an average of 5.6 years. At entry, 5.6% had roentgenographic evidence of ON in one or both shoulders. There was little difference in age-adjusted prevalence among genotypes, but there were striking differences in age-specific rates. Observed at ages ranging from five to 24 years, 3.25% of sickle cell anemia (S/S) patients, but only 1.1% of sickle cell disease (S/C) patients, had ON. No S/beta+ thalassemia patients younger than 25 years of age had ON on entry. The highest age-adjusted incidence rate was found in S/S patients with concomitant alpha-thalassemia (4.85 per hundred patient-years), followed by S/beta zero-thalassemia (4.84 per hundred patient-years), S/beta+ thalassemia (2.61 per hundred patient-years), S/S without alpha-thalassemia (2.54 per hundred patient-years), and S/C (1.66 per hundred patient-years). Only 20.9% of patients reported pain or had limited range of movement at the time of diagnosis. Sickle cell disease is a frequent cause of ON of the humeral head, especially in children and young adults.

Sickle cell disease as a cause of osteonecrosis of the femoral head

BACKGROUND AND METHODS

Osteonecrosis of the femoral head is an important complication of sickle cell disease. We studied 2590 patients who were over 5 years of age at entry and followed them for an average of 5.6 years. Patients were examined twice a year, and radiographs of the hips were taken at least twice: at study entry and approximately three years later.

RESULTS

At study entry, 9.8 percent of patients were found to have osteonecrosis of one or both femoral heads. On follow-up, patients with the hemoglobin SS genotype and alpha-thalassemia were at the greatest risk for osteonecrosis (age-adjusted incidence rate, 4.5 cases per 100 patient-years, as compared with 2.4 in patients with the hemoglobin SS genotype without alpha-thalassemia and 1.9 in those with the hemoglobin SC genotype). Although the rate of osteonecrosis in patients with the hemoglobin SC genotype did not differ significantly from that in patients with the hemoglobin SS genotype without alpha-thalassemia, osteonecrosis tended to develop in these patients later in life. Intermediate rates of osteonecrosis were observed among patients with the hemoglobin S-beta zero-thalassemia and the hemoglobin S-beta(+)-thalassemia genotypes (3.6 and 3.3 cases per 100 patient-years, respectively). Osteonecrosis was found in patients as young as five years old (1.8 cases per 100 patient-years for all genotypes). The frequency of painful crises and the hematocrit were positively associated with osteonecrosis. The mean corpuscular volume and serum aspartate aminotransferase level were negatively associated. Twenty-seven patients had hip arthroplasty during the study; 10 were under 25 years of age. Five of the 27 required reoperation 11 to 53 months after the initial operation.

CONCLUSIONS

Osteonecrosis of the femoral head is common in patients with sickle cell disease, with an incidence ranging from about 2 to 4.5 cases per 100 patient-years. Patients with the hemoglobin SS genotype and alpha-thalassemia and those with frequent painful crises are at highest risk. The overall prevalence is about 10 percent. The results of hip arthroplasty are poor.