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T D Koepsell

Publications and source records attributed to T D Koepsell.

At least 19 recordsLinked to original sources
PubMed2000

Effect of a ban on carrying firearms on homicide rates in 2 Colombian cities.

CONTEXT: Homicide is a leading cause of death in Colombia, with much of the fatal interpersonal violence concentrated in the country's largest cities. Firearms are involved in as much as 80% of homicides in Colombia. OBJECTIVE: To evaluate the effect of an intermittent police-enforced ban on carrying firearms on the incidence of homicide in urban Colombia. DESIGN: Interrupted time-series study with multiple replications. SETTING: Cali, Colombia, during 1993 and 1994 and Bogotá, Colombia, from 1995 through August 1997. PARTICIPANTS: The populations of Cali and Bogotá. INTERVENTION: Carrying of firearms was banned on weekends after paydays, on holidays, and on election days. Enforcement included establishment of police checkpoints and searching of individuals during traffic stops and other routine law enforcement activity. MAIN OUTCOME MEASURE: Homicide rates during intervention days were compared with rates during similar days without the intervention; estimates were based on comparisons within the same month, day of week, and time of day. RESULTS: There were 4078 homicides in Cali during 1993 and 1994 (114.6 per 100,000 person-years). In Bogotá, 9106 homicides occurred from 1995 through August 1997 (61 per 100,000 person-years). The incidence of homicide was lower during periods when the firearm-carrying ban was in effect compared with other periods (multivariate-adjusted rate ratio, 0.86 [95% confidence interval [CI], 0.76-0.97] for Cali, and 0.87 [95% CI, 0.77-0.98] for Bogotá). CONCLUSION: An intermittent citywide ban on the carrying of firearms in 2 Colombian cities was associated with a reduction in homicide rates for both cities.

Adolescent↗
PubMed2000

US Department of Veterans Affairs medical care system as a resource to epidemiologists.

Epidemiologists have utilized several health care systems with large numbers of enrollees and centralized databases to achieve their research aims. Although containing many of the features that have made certain health care systems valuable to the conduct of epidemiologic research, the US Department of Veterans Affairs (VA) medical care system has not been well utilized by epidemiologists. This article will describe existing and planned features of this health care system that should be of interest to epidemiologists, including centralized databases that capture hospital discharge and outpatient clinic diagnostic data, a planned enrollment file that would contain all persons eligible for VA medical care, and the size and national dispersion of VA medical care facilities. Also, VA leadership has demonstrated an interest in the promotion of epidemiologic research by initiating several new programs, including the creation of three Epidemiologic Research and Information Centers (ERICs) to foster VA epidemiologic research, and announcing a program to support investigator-initiated epidemiologic research projects with VA funding. Epidemiologists with interests in medical problems that afflict veterans should consider partnerships with VA investigators to achieve their research aims.

Epidemiologic Methods↗
PubMed2000

Apolipoprotein E genotype and the risk of gallbladder disease in pregnancy.

The E4 allele of apolipoprotein E (apoE4) has previously been associated with symptomatic gallstone disease. The aim of this study was to determine if apoE4 is associated with the development of gallbladder sludge and/or stones during pregnancy. We conducted a nested case-control study based on an ongoing cohort study of gallbladder disease in pregnancy. Women in this study receive gallbladder ultrasounds in each trimester of pregnancy. Cases (n = 52) were defined as women with incident gallbladder sludge or stones diagnosed at the third trimester ultrasound. Controls (n = 104) were defined as women without gallbladder sludge or stones on any of 3 study ultrasounds. ApoE genotyping was performed from stored white blood cell pellets. Data were analyzed by stratified analysis and multivariate logistic regression. Cases and controls were similar in baseline characteristics. Forty-two women had sludge, 6 had gallstones, and 4 had both sludge and stones. After adjusting for risk factors such as age, parity, and body mass index, the odds ratio (OR) for the association between heterozygosity or homozygosity for the apoE4 allele and incident gallbladder sludge or stones was 0.91 (95% confidence interval [CI], 0.41-2.02). Further adjustment for family medical history and serum lipid levels did not substantially change these results (OR, 0.73; 95% CI, 0.29-1.82). In conclusion, apoE4 appears to have little or no overall association with the development of new gallbladder sludge or stones in pregnancy. However, an effect could not be ruled out in certain subgroups, such as blacks or women who are homozygous for apoE4.

Apolipoprotein E4↗
PubMed2000

Delivery of primary care to women. Do women's health centers do it better?

OBJECTIVE: Women's health centers have been increasing in number but remain relatively unstudied. We examined patient expectations and quality of care at a hospital-based women's health center compared with those at a general medicine clinic. DESIGN: Cross-sectional survey. SETTING: University hospital-affiliated women's health and general internal medicine clinics. PARTICIPANTS: An age-stratified random sample of 2,000 women over 18 years of age with at least two visits to either clinic in the prior 24 months. We confined the analysis to 706 women respondents who identified themselves as primary care patients of either clinic. MEASUREMENTS AND MAIN RESULTS: Personal characteristics, health care utilization, preferences and expectations for care, receipt of preventive services, and satisfaction with provider and clinic were assessed for all respondents. Patients obtaining care at the general internal medicine clinic were older and had more chronic diseases and functional limitations than patients receiving care at the women's health center. Women's health center users (n = 357) were more likely than general medicine clinic users ( n = 349) to prefer a female provider ( 57% vs 32%, p =.0001) and to have sought care at the clinic because of its focus on women's health (49% vs 17%, p =. 0001). After adjusting for age and self-assessed health status, women's health center users were significantly more likely to report having had mammography (odds ratio [OR] 4.0, 95% confidence interval [CI] 1.1, 15.2) and cholesterol screening (OR 1.6, 95% CI 1.0, 2.6) but significantly less likely to report having undergone flexible sigmoidoscopy (OR 0.5, 95% CI 0.3, 0.9). There were no significant differences between the clinics on receipt of counseling about hormone replacement therapy or receipt of Pap smear, or in satisfaction. CONCLUSIONS: These results suggest that, at least in this setting, women's health centers provide care to younger women and those with fewer chronic medical conditions and may meet a market demand. While the quality of gender-specific preventive care may be modestly better in women's health centers, the quality of general preventive care may be better in general medical clinics.

Adolescent↗
PubMed2000

High-risk periods for childhood injury among siblings.

OBJECTIVE: To determine whether the risk of unintentional injury requiring emergency department (ED) or inpatient care in children is transiently increased over a 90-day period after injury to a sibling. DESIGN: Retrospective cohort. SETTING: King County, Washington. Participants. A total of 41 242 children 0 to 15 years of age continuously enrolled in Medicaid and living in King County during the period October 1, 1992 through September 30, 1993 (27 450 child-years). OUTCOME MEASURES: The outcome was an unintentional injury treated in the ED or inpatient setting. Incidence rates and hazard ratios were calculated for children whose sibling had been injured in the previous 90 days, compared with children without such exposure. Multivariate analysis was used to adjust for age, gender, race, sibling group size, and noninjury ED use. RESULTS: . There were 4921 injuries treated only in the ED and 82 hospital admissions. The incidence of ED treated injury was 305 per 1000 child-years among children whose sibling had been injured in the previous 90 days and 174 per 1000 child-years among children without this exposure (relative risk: 1.75; 95% confidence interval: 1.56-1.95). The incidence of injury-related hospitalization was 1.7 per 1000 child-years among children whose sibling had been injured in the previous 90 days, compared with 3.0 per 1000 child-years among children without this exposure (relative risk:.57; 95% confidence interval:.07-2.12). Injury risk peaked in the period 4 to 10 days after a sibling's injury and returned toward, but did not attain, baseline risk over the subsequent 21/2 months. The magnitude of this effect depended on the child's age; the relative risk of injury was higher among older children. CONCLUSIONS: Injuries treated in the ED or inpatient setting appear to cluster within sibling groups over brief periods of time. Shared social or environmental exposures may contribute to this clustering and may be amenable to targeted, time-limited prevention interventions.

Adolescent↗
PubMed1999

A comparison of pain, functional limitations, and work status indices as outcome measures in back pain research.

STUDY DESIGN: We conducted a prospective study with a 2-year follow-up. OBJECTIVE: To compare pain, functional limitations, and work status indices as measures of outcome among back pain patients. SUMMARY OF BACKGROUND DATA: Work status, pain, and functional limitations indices are often considered as interchangeable outcome measures in back pain research. This perspective has been criticized by several authors, who argue that each of these outcome measures reflects a different construct that may vary independently of the others. METHODS: The study was conducted on 720 patients, who sought care for back pain in primary care settings of a large health maintenance organization in 1989-90, and were interviewed one month and two years later. X2 analyses and receiver operating characteristic curves were used to compare the accuracy of a pain rating and a modified 16-item Roland-Morris score in classifying patients on work status and on the change in work status over time. RESULTS: Moderate agreement between the pain and functional limitations measures and work status was observed. Pain and functional limitations change scores agreed moderately with improvement in work status, but were poorly associated with decline in work status. CONCLUSIONS: Although the pain, functional limitations, and work status indices examined in this study are related, they are not equivalent and should not be regarded as interchangeable. These results argue for a clearer distinction of outcome measures in back pain research.

Adult↗
PubMed1999

Trends in the post-hospitalization medical treatment of unstable angina pectoris: 1990 to 1995.

This study provides data on post-hospitalization medication treatment trends for unstable angina between 1990 and 1995. We conducted an observational cohort study at the Veterans Affairs Puget Sound Health Care System (VAPSHCS). Computerized records of hospital discharges and cardiac catheterizations were used to identify unstable angina diagnoses among veterans between 1990 and 1995. Discharge medications issued within 90 days after discharge were ascertained from computerized outpatient pharmacy records. Of the 1,100 veterans discharged with unstable angina, 885 (80%) filled a prescription through the VAPSHCS within 90 days after discharge. Neither use of aspirin nor use of beta blockers increased between 1990 and 1995: overall use averaged 76% for aspirin (78% of those without potential contraindications) and 32% for beta blockers (36% of those without potential contraindications). Use of non-dihydropyridine calcium antagonists--primarily diltiazem--decreased from 57% to 40% (p <0.01), whereas use of dihydropyridine calcium antagonists increased from 12% to 26% (p <0.01). Thus, pharmacy records indicated that aspirin use was high although it was lower than expected, possibly due to ready availability outside the VAPSHCS pharmacy. The low frequency of beta-blocker use and the increasing reliance on dihydropyridine calcium antagonists through 1995 to treat unstable angina may be an opportunity to improve veteran care according to Agency for Health Care Policy Research recommendations.

Adrenergic beta-Antagonists↗
PubMed1999

Increasing response rates for mailed surveys of Medicaid clients and other low-income populations.

Mailing surveys to low-income populations is often avoided because of concern about low response rates. In this study, the authors used a mailed survey of a low-income population to test whether $1.00 or $2.00 cash-response incentives were worth the expense and whether 2-day priority mail ($2.90 postage) would yield a sufficiently higher response rate than certified mail ($1.52 postage) to justify its cost. In 1994, 2,243 randomly selected families in subsidized health care programs in Pierce County, Washington, were randomly sent no incentive, $1.00, or $2.00 in the first of three mailings. For the third mailing, nonrespondents were randomly assigned to receive either certified or 2-day priority mail. After 4 weeks, the response rates were 36.7%, 48.1%, and 50.3% for the no-incentive, $1.00, and $2.00 groups, respectively. After three mailings, the cost per response was the lowest for the group that received $1.00. The response rate for the certified mailing (28.1%) was significantly higher than the rate for the more expensive priority mailing (21.7%). No incentive-related bias was detected. The authors concluded that the most efficient protocol for this low-income population was to use a $1.00 incentive in the first mailing and a certified third mailing.

Aged↗
PubMed1999

Patient-physician racial concordance and the perceived quality and use of health care.

BACKGROUND: Patients from racial and ethnic minority groups use fewer health care services and are less satisfied with their care than patients from the majority white population. These disparities may be attributable in part to racial or cultural differences between patients and their physicians. OBJECTIVE: To determine whether racial concordance between patients and physicians affects patients' satisfaction with and use of health care. METHODS: We analyzed data from the 1994 Commonwealth Fund's Minority Health Survey, a nationwide, telephone survey of noninstitutionalized adults. For the 2201 white, black, and Hispanic respondents who reported having a regular physician, we examined the association between patient-physician racial concordance and patients' ratings of their physicians, satisfaction with health care, reported receipt of preventive care, and reported receipt of needed medical care. RESULTS: Black respondents with black physicians were more likely than those with nonblack physicians to rate their physicians as excellent (adjusted odds ratio [OR], 2.40; 95% confidence interval [CI], 1.55-3.72) and to report receiving preventive care (adjusted OR, 1.74; 95% CI, 1.01-2.98) and all needed medical care (adjusted OR, 2.94; 95% CI, 1.10-7.87) during the previous year. Hispanics with Hispanic physicians were more likely than those with non-Hispanic physicians to be very satisfied with their health care overall (adjusted OR, 1.74; 95% CI, 1.01-2.99). CONCLUSIONS: Our findings confirm the importance of racial and cultural factors in the patient-physician relationship and reaffirm the role of black and Hispanic physicians in caring for black and Hispanic patients. Improving cultural competence among physicians may enhance the quality of health care for minority populations. In the meantime, by reducing the number of underrepresented minorities entering the US physician workforce, the reversal of affirmative action policies may adversely affect the delivery of health care to black and Hispanic Americans.

Adult↗
PubMed1999

Explaining community-level variance in group randomized trials.

Between-community variance or community-by-time variance is one of the key factors driving the cost of conducting group randomized trials, which are often very expensive. We investigated empirically whether between-community variance could be reduced by controlling individual- and/or community-level covariates and identified these covariates from four large community-based group randomized trials or surveys: the Working Well Trial; Kaiser Adolescent Survey; Kaiser Adults Survey; and the Eating Patterns Study. We found that adjusting for covariates will often substantially reduce the between-community variance component. Therefore investigators could block the communities according to these covariates, or adjust for these covariates to improve the power of community trials. We found that the community-by-time variance components are always near zero in these data sets, especially for the surveys where a cohort was followed over time. The covariate adjustment had less impact on reducing the community-by-time variance for the cohort samples than for the cross-sectional samples. This suggests that blocking may not be necessary for the design of the group randomized trials where the change from baseline is of primary interest. The Working Well Trial data were used to illustrate this point.

Adolescent↗
PubMed1999

Lipid-lowering medication and risk of injury.

Meta-analyses of early primary prevention trials of lipid-lowering therapies suggested increased risk of injury deaths among treated persons. Our population-based case-control study examined the association of lipid-lowering medication use with fatal and nonfatal injuries in 298 cases and 332 controls. No increased injury risk was observed among current (OR = 0.46, 95% CI 0.18-1.21) or past users (OR = .92, 95% CI 0.44-1.95), after adjustment for behavioral disorders, medical conditions, and health status. Stratified analyses did not reveal sub-groups at significantly increased risk. These results, consistent with recent clinical trials and meta-analyses, suggest no increased injury risk associated with lipid-lowering medications.

Accidents, Home↗
PubMed1999

Assessment and control for confounding by indication in observational studies.

In the evaluation of pharmacologic therapies, the controlled clinical trial is the preferred design. When clinical trial results are not available, the alternative designs are observational epidemiologic studies. A traditional concern about the validity of findings from epidemiologic studies is the possibility of bias from uncontrolled confounding. In studies of pharmacologic therapies, confounding by indication may arise when a drug treatment serves as a marker for a clinical characteristic or medical condition that triggers the use of the treatment and that, at the same time, increases the risk of the outcome under study. Confounding by indication is not conceptually different from confounding by other factors, and the approaches to detect and control for confounding--matching, stratification, restriction, and multivariate adjustment--are the same. Even after adjustment for known risk factors, residual confounding may occur because of measurement error or unmeasured or unknown risk factors. Although residual confounding is difficult to exclude in observational studies, there are limits to what this "unknown" confounding can explain. The degree of confounding depends on the prevalence of the putative confounding factor, the level of its association with the disease, and the level of its association with the exposure. For example, a confounding factor with a prevalence of 20% would have to increase the relative odds of both outcome and exposure by factors of 4 to 5 before the relative risk of 1.57 would be reduced to 1.00. Observational studies have provided important scientific evidence about the risks associated with several risk factors, including drug therapies, and they are often the only option for assessing safety. Understanding the methods to detect and control for confounding makes it possible to assess the plausibility of claims that confounding is an alternative explanation for the findings of particular studies.

Antihypertensive Agents↗
PubMed1999

Mortality, health services use, and health behavior in a cohort of well older adults.

OBJECTIVES: To construct an evidence-based Good Health Behavior Score and examine the relationship between aggregate health behaviors, mortality, and health services utilization in the last year of life in a cohort of well older adults. DESIGN: A prospective cohort. SETTING: A large health maintenance organization. PARTICIPANTS: 1867 older enrollees who responded to a health promotion survey. MEASUREMENTS: A baseline self-administered questionnaire was used to ascertain health behaviors in 1987-1988, and vital status was determined 48 months later. A Good Health Behavior Score was calculated, and a Cox proportional hazards model was used to compare high, middle, and low score groups regarding risk of death. For those who died, differences in amount and type of health services utilization in relation to the summary score were compared for the year before death. RESULTS: During the 4 years of follow-up, the mortality rate for the mid-level score group was 50% less, and in the highest score group was 70% less, than in the lowest score group. Among decedents, no significant differences were found between high and low Good Health Behavior score groups for inpatient and outpatient utilization, pharmacy use, or total cost during the last year of life. CONCLUSION: An easily developed and simple health behavior score can predict short term mortality quite strongly. Medical care costs in the last year of life were similar in individuals with higher and lower health behavior scores.

Aged↗
PubMed1999

Cervical spine imaging in patients with trauma: determination of fracture risk to optimize use.

PURPOSE: To develop a method to use clinically apparent factors to determine cervical spine fracture risk to guide selection of optimal imaging strategies. MATERIALS AND METHODS: Records from 472 patients with trauma (168 with fractures, 304 control patients) who visited the emergency department in 1994 and 1995 were reviewed for 20 potential predictors of cervical spine fracture in this retrospective case-control study. Simple logistic regression was used to determine predictors of cervical spine fracture. Prediction rules were formulated by using multiple logistic regression and recursive partitioning with bootstrap validation. Posttest fracture probabilities were calculated from base prevalence and likelihood ratios derived for predictors by using Bayes theorem. RESULTS: Predictors of cervical spine fracture included severe head injury (adjusted odds ratio [OR] = 8.5, 95% CI: 4.0, 17.0), high-energy cause (OR = 11.6, 95% CI: 5.4, 25.0), and focal neurologic deficit (OR = 58, 95% CI: 12, 283). The prediction rule was used to stratify patients into groups with fracture probabilities of 0.04%-19.70%. After adjusting for overfitting, the area under the receiver operating characteristic curve was 0.87. CONCLUSION: Clinically apparent factors, including cause of injury, associated injuries, and age, can be used to determine the probability of cervical spine fracture. Development of evidence-based imaging guidelines should incorporate knowledge of fracture probability.

Adult↗
PubMed1999

Is greater continuity of care associated with less emergency department utilization?

BACKGROUND: The benefits of continuity of care (COC) have not been firmly established for pediatric patients. OBJECTIVE: To assess whether greater COC is associated with lower emergency department (ED) utilization. SETTING: Outpatient teaching clinic at Children's Hospital and Regional Medical Center, Seattle, WA. PATIENTS: All 785 Medicaid managed care children ages 0 to 19 years followed at Children's Hospital and Regional Medical Center between 1993 to 1997 who had at least four outpatient visits. METHODS: Retrospective claims-based analysis. COC was quantified based on the number of different care providers in relation to the number of clinic visits. RESULTS: Attending COC was significantly greater than resident COC. In a multiple event survival analysis, compared with those patients in the lowest tertile of attending COC, those in the middle tertile had 30% lower ED utilization (hazard ratio 0.70 [0.53-0.93]) and those in the highest tertile had 35% lower ED use (hazard ratio 0.65 [0.50-0.80]). Resident COC was not significantly associated with ED use. CONCLUSION: Greater COC with attending physicians in outpatient teaching clinics is associated with lower ED utilization.

Adolescent↗
PubMed1999

Incidence and outcome of injury in Ghana: a community-based survey.

Injury is an increasingly significant health problem in most low-income countries. However, strategies for preventing injury have not been well addressed. The present study was carried out to measure the incidence and outcome of various mechanisms of injury in Ghana in order to provide data for use in developing priorities for injury prevention efforts. For this purpose, using two-stage cluster sampling and household interviews, we surveyed 21,105 persons living in 431 urban and rural sites. During the preceding year, 1609 injuries resulting in one or more days of loss of normal activity were reported. Injury-related mortality was slightly higher in the urban (83 per 100,000) than in the rural area (53 per 100,000). However, the burden of disability from nonfatal injuries, as assessed by disability days, was higher in the rural (4697 disability days per 1000 person-years) than in the urban area (2671 days per 1000 person-years). Based on incidence rates and disability times, the major types of injury in the urban area were transport-related injury and falls. In the rural area, agricultural injuries predominated, followed by falls and transport-related injury. In rural and urban areas combined, 73% of motor vehicle-related injuries involved commercial vehicles. In this and other similar developing-country settings, injury prevention efforts should focus on falls and on transport safety in both urban and rural areas, with special attention being paid to commercial vehicles. In rural areas, agricultural injuries contributed the largest burden of morbidity, and should be a priority for prevention efforts.

Adolescent↗
PubMed1998

Myocardial infarction and use of low-dose oral contraceptives: a pooled analysis of 2 US studies.

BACKGROUND: Population-based case-control studies to assess the relationship of low-dose oral contraceptive (OC) use with myocardial infarction (MI) were performed at 2 sites in the United States (California and Washington state). The purpose of the present study was to estimate risk of MI in relation to use of low-dose OCs in a pooled analysis combining results from the 2 sites. METHODS AND RESULTS: The study included as cases women aged 18 to 44 years with incident MI who had no prior history of ischemic heart disease or cerebrovascular disease. Women in the case and control groups were interviewed in person regarding OC use and cardiovascular risk factors. The analysis included 271 MI cases and 993 controls. Compared with noncurrent users, the adjusted pooled odds ratio for MI in current OC users was 0.94 (95% CI, 0.44, 2.20) after adjustment for major risk factors and sociodemographic factors. Compared with never users, the adjusted pooled odds ratio for MI was 0.56 (0.21, 1.49) in current OC users and 0.54 (0.31, 0.95) in past OC users. Among past OC users, duration and recency of use were unrelated to MI risk as was current hormone replacement therapy. There was no evidence of interaction between OC use and age, presence of cardiovascular risk factors (hypercholesterolemia, hypertension, diabetes), obesity, or smoking. CONCLUSIONS: We conclude that low-dose OCs as used in these populations are safe with respect to risk of MI in women.

Adolescent↗