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Biomedical subjects

R V Luepker

Publications and source records attributed to R V Luepker.

At least 19 recordsLinked to original sources

The impact of the Women's Health Initiative on discontinuation of postmenopausal hormone therapy: the Minnesota Heart Survey (2000-2002).

BACKGROUND: The Women's Health Initiative (WHI) Data Safety and Monitoring Board terminated the trial arm of the estrogen plus progestin combined hormone therapy early after observing an excess of harm relative to benefit of this therapy. METHODS: To learn how postmenopausal hormone therapy (PMT) use in a community setting was affected by the WHI results, we resurveyed current users of PMT in August 2002 to January 2003 after publication of the WHI findings from our Minnesota Heart Survey (MHS) cohort (2000-2002), a cross-sectional epidemiological survey in the Minneapolis-St. Paul, Minnesota, area. We evaluated women's interpretation of the WHI results, reports of their physicians' recommendations, and the impact of these on PMT use in this group. RESULTS: We obtained an excellent response rate (97.9%, 185 of 189). Almost a third of women with an intact uterus but few women with a hysterectomy discontinued their PMT regimen within the first 6 months after the WHI research results were released. The majority of women in our study consulted their physician about whether to discontinue PMT. Women in the intact uterus group who started their PMT regimen for menopausal symptoms were less likely to discontinue PMT. Of women who continued their PMT regimen, the majority cited relief of menopausal symptoms or physician recommendation for continuation of PMT or both. Almost a third of the women interviewed reported being confused, worried, or nervous about the media reports of the WHI results. CONCLUSIONS: These results suggest effective dissemination of WHI information by the media and physicians and significant changes in patterns of PMT use in the community.

Adult↗

Trends in acute coronary heart disease mortality, morbidity, and medical care from 1985 through 1997: the Minnesota heart survey.

BACKGROUND: Coronary heart disease (CHD) mortality continued to decline from 1985 to 1997. METHODS AND RESULTS: We tabulated CHD deaths (ICD-9 codes 410 through 414) in the Minneapolis/St Paul, Minnesota, area. For 1985, 1990, and 1995, trained nurses abstracted the hospital records of patients 30 to 74 years old with a discharge diagnosis of acute CHD (ICD-9 codes 410 or 411). Acute myocardial infarction (AMI) events were validated and followed for 3-year all-cause mortality. Between 1985 and 1997, age-adjusted CHD mortality rates in Minneapolis/St Paul fell 47% and 51% in men and women, respectively; the comparable declines in US whites were 34% and 29%. In-hospital mortality declined faster than out-of-hospital mortality. The rate of AMI (ICD-9 code 410) hospital discharges declined almost 20% between 1985 and 1995, whereas the discharge rate for unstable angina (ICD-9 code 411) increased substantially. The incidence of hospitalized definite AMI declined approximately 10%, whereas recurrence rates fell 20% to 30%. Three-year case fatality rates after hospitalized AMI decreased consistently by 31% and 41% in men and women, respectively. In-hospital administration of thrombolytic therapy, emergency angioplasty, ACE inhibitors, beta-blockers, heparin, and aspirin increased greatly. CONCLUSIONS: Declining out-of-hospital death rates, declining incidence and recurrence of AMI in the population, and marked improvements in the survival of AMI patients all contributed to the 1985 to 1997 decline of CHD mortality in the Minneapolis/St Paul metropolitan area. The effects of early and late medical care seem to have had the greatest contribution to rates during this time period.

Acute Disease↗

Characteristics and outcomes among patients undergoing coronary artery bypass grafting in western Sweden and Minneapolis-St Paul, Minnesota.

BACKGROUND: The purpose of this study was to compare patient selection, operative factors, and survival for coronary artery bypass grafting (CABG) for coronary heart disease in Minneapolis-St Paul (MSP), Minnesota, and Western Sweden (WS). METHODS AND RESULTS: All patients from WS between 1988 and 1991 (n = 2365) and a 17% random sample of MSP patients between 1985 and 1990 (n = 1659) who underwent CABG surgery were studied. CABG was 3 times greater in MSP. MSP patients had significantly more obesity, cigarette smoking, prior CABG, and prior coronary angioplasty. WS patients had more and longer angina pectoris, better left ventricular function, and waited longer from previous acute MI until CABG. WS patients had more internal mammary artery graphs and a shorter aortic cross-clamp time. At discharge, WS patients received more beta-blockers and antiplatelet agents, whereas MSP patients received more calcium channel blockers and digitalis. Age-adjusted mortality rate at 28 days was significantly higher in MSP but not at 3 years. Adjustment for patient characteristics and treatment factors reduced or eliminated these differences. CONCLUSIONS: Although coronary heart disease rates were higher in WS, age-adjusted CABG rates were 3-fold higher in MSP. Better survival among WS patients was associated with differences in patient selection and clinical and treatment characteristics because MSP patients were more severely ill and at increased risk. Health system characteristics and practice may account for these differences.

Adult↗

Secular trends in dietary macronutrient intake in Minneapolis-St, Paul, Minnesota, 1980-1992.

Trends in dietary macronutrient intake were evaluated in population-based surveys conducted in adults aged 25-74 years in 1980-1982, 1985-1987, and 1990-1992 in the seven-county Minneapolis-St. Paul metropolitan area. A 24-hour dietary recall (n = 6,499) was completed by a random 50% sample. The authors obtained energy intake for each macronutrient (protein, carbohydrate, fat, saturated fat, monounsaturated fat, polyunsaturated fat, and alcohol). Tine trends for percentage of total energy were analyzed using a generalized linear mixed model. While energy intake remained stable over time, macronutrient composition changed substantially. In 1980-1982, the caloric distribution for men comprised 15.8% protein, 39.4% fat, 40.9% carbohydrate, and 3.9% alcohol; similar findings were observed in women (15.7% protein, 38.9% fat, 43% carbohydrate, and 2.4% alcohol). From 1980 to 1992, total fat intake decreased 4.7% in men and 4.9% in women (p < 0.001). The decline was greatest for monounsaturated fat, although saturated and polyunsaturated fat intake also fell. During this same period, carbohydrate intake increased 5.7% and 5.8% in men and women, respectively (p < 0.001). Alcohol intake decreased in men and women (p < 0.01), while protein intake remained stable. In summary, the Minneapolis-St. Paul metropolitan area diet shifted substantially during the 1980s toward more carbohydrate and lower fat and alcohol intake.

Adult↗

Effect of a community intervention on patient delay and emergency medical service use in acute coronary heart disease: The Rapid Early Action for Coronary Treatment (REACT) Trial.

CONTEXT: Delayed access to medical care in patients with acute myocardial infarction (AMI) is common and increases myocardial damage and mortality. OBJECTIVE: To evaluate a community intervention to reduce patient delay from symptom onset to hospital presentation and increase emergency medical service (EMS) use. DESIGN AND SETTING: The Rapid Early Action for Coronary Treatment Trial, a randomized trial conducted from 1995 to 1997 in 20 US cities (10 matched pairs; population range, 55,777-238,912) in 10 states. PARTICIPANTS: A total of 59,944 adults aged 30 years or older presenting to hospital emergency departments (EDs) with chest pain, of whom 20,364 met the primary population criteria of suspected acute coronary heart disease on admission and were discharged with a coronary heart disease-related diagnosis. INTERVENTION: One city in each pair was randomly assigned to an 18-month intervention that targeted mass media, community organizations, and professional, public, and patient education to increase appropriate patient actions for AMI symptoms (primary population, n=10,563). The other city in each pair was randomly assigned to reference status (primary population, n=9801). MAIN OUTCOME MEASURES: Time from symptom onset to ED arrival and EMS use, compared between intervention and reference city pairs. RESULTS: General population surveys provided evidence of increased public awareness and knowledge of program messages. Patient delay from symptom onset to hospital arrival at baseline (median, 140 minutes) was identical in the intervention and reference communities. Delay time decreased in intervention communities by -4.7% per year (95% confidence interval [CI], -8.6% to -0.6%), but the change did not differ significantly from that observed in reference communities (-6. 8% per year; 95% CI, -14.5% to 1.6%; P=.54). EMS use by the primary study population increased significantly in intervention communities compared with reference communities, with a net effect of 20% (95% CI, 7%-34%; P<.005). Total numbers of ED presentations for chest pain and patients with chest pain discharged from the ED, as well as EMS use among patients with chest pain released from the ED, did not change significantly. CONCLUSIONS: In this study, despite an 18-month intervention, time from symptom onset to hospital arrival for patients with chest pain did not change differentially between groups, although increased appropriate EMS use occurred in intervention communities. New strategies are needed if delay time from symptom onset to hospital presentation is to be decreased further in patients with suspected AMI. JAMA. 2000;284:60-67

Acute Disease↗

Differences and trends in antioxidant dietary intake in smokers and non-smokers, 1980-1992: the Minnesota Heart Survey.

PURPOSE: Differences and secular trends in dietary antioxidant vitamin intake (vitamins E, C, and beta-carotene) in current non-smokers, light smokers, and heavy smokers were examined as part of the Minnesota Heart Survey. METHODS: Three cross-sectional surveys were conducted in adults ages 25-74 years in 1980-82 (N = 1682), 1985-87 (N = 2326), and 1990-92 (N = 2487). Dietary information was obtained from a 24-hour dietary recall. Smoking was assessed through self-report. Intakes were adjusted for age, energy intake, body mass index, education level, and exercise level (vitamins E, C and beta-carotene). RESULTS: Antioxidant vitamin intakes were significantly higher in non-smokers than in light (1-20 cig/day) and heavy smokers (>20 cig/day) when all three survey periods were combined. In men, mean vitamin E intake was 9.2 mg, 8.6 mg, and 7.8 mg for non-smokers, light smokers, and heavy smokers, respectively. Results were similar in men for beta-carotene (non-smokers 1408 microg, light smokers 1287 microg, and heavy smokers 1064 microg), and vitamin C (non-smokers 81 mg, light smokers 67 mg, and heavy smokers 56 mg). Women had results of similar magnitude and direction. From 1980-92, secular trends in men showed non-significant increases from 1980-82 to 1990-92 in beta-carotene (+6.1%), while decreases were observed in vitamins E (-1.1%) and C (-2.6%). In contrast, women had large decreases in all antioxidant vitamin intakes: vitamin E (-13%), vitamin C (-18.6%), and beta-carotene (-16.2%). CONCLUSIONS: Light and heavy smokers had a significantly lower overall mean dietary antioxidant vitamin intake than non-smokers. Over the decade, antioxidant dietary intake remained relatively stable in men and decreased in women in Minneapolis-St. Paul, despite improvements in access to antioxidant rich fruits and vegetables.

Adult↗

Impact of community intervention to reduce patient delay time on use of reperfusion therapy for acute myocardial infarction: rapid early action for coronary treatment (REACT) trial. REACT Study Group.

BACKGROUND: Reperfusion therapy for acute myocardial infarction (AMI) is a time-dependent intervention that can reduce infarct-related morbidity and mortality. Out-of-hospital patient delay from symptom onset until emergency department (ED) presentation may reduce the expected benefit of reperfusion therapy. OBJECTIVE: To determine the impact of a community educational intervention to reduce patient delay time on the use of reperfusion therapy for AMI. METHODS: This was a randomized, controlled community-based trial to enhance patient recognition of AMI symptoms and encourage early ED presentation with resultant increased reperfusion therapy rates for AMI. The study took place in 44 hospitals in 20 pair-matched communities in five U.S. geographic regions. Eligible study subjects were non-institutionalized patients without chest injury (aged > or =30 years) who were admitted to participating hospitals and who received a hospital discharge diagnosis of AMI (ICD 410); n = 4,885. For outcome assessment, patients were excluded if they were without survival data (n = 402), enrolled in thrombolytic trials (n = 61), receiving reperfusion therapy >12 hours after ED arrival (n = 628), or missing symptom onset or reperfusion times (n = 781). The applied intervention was an educational program targeting community organizations and the general public, high-risk patients, and health professionals in target communities. The primary outcome was a change in the proportion of AMI patients receiving early reperfusion therapy (i.e., within one hour of ED arrival or within six hours of symptom onset). Trends in reperfusion therapy rates were determined after adjustment for patient demographics, presenting blood pressure, cardiac history, and insurance status. Four-month baseline was compared with the 18-month intervention period. RESULTS: Of 3,013 selected AMI patients, 40% received reperfusion therapy. Eighteen percent received therapy within one hour of ED arrival (46% of treated patients), and 32% within six hours of symptom onset (80% of treated patients). No significant difference in the trends in reperfusion therapy rates was attributable to the intervention, although increases in early reperfusion therapy rates were noted during the first six months of the intervention. A significant association of early reperfusion therapy use with ambulance use was identified. CONCLUSIONS: Community-wide educational efforts to enhance patient response to AMI symptoms may not translate into sustained changes in reperfusion practices. However, an increased odds for early reperfusion therapy use during the initiation of the intervention and the association of early therapy with ambulance use suggest that reperfusion therapy rates can be enhanced.

Adult↗

Reducing the progression of myopia with atropine: a long term cohort study of Olmsted County students.

BACKGROUND: Myopia is an important public health problem because it is common and is associated with increased risk for chorioretinal degeneration, retinal detachment, and other vision- threatening abnormalities. In animals, ocular elongation and myopia progression can be lessened with atropine treatment. This study provides information about progression of myopia and atropine therapy for myopia in humans. METHODS: A total of 214 residents of Olmsted County, Minnesota (118 girls and 96 boys, median age, 11 years; range 6 to 15 years) received atropine for myopia from 1967 through 1974. Control subjects were matched by age, sex, refractive error, and date of baseline examination to 194 of those receiving atropine. Duration of treatment with atropine ranged from 18 weeks to 11.5 years (median 3.5 years). RESULTS: Median followup from initial to last refraction in the atropine group (11.7 years) was similar to that in the control group (12.4 years). Photophobia and blurred vision were frequently reported, but no serious adverse effects were associated with atropine therapy. Mean myopia progression during atropine treatment adjusted for age and refractive error (0.05 diopters per year) was significantly less than that among control subjects (0.36 diopters per year)(P<.001). Final refractions standardized to the age of 20 years showed a greater mean level of myopia in the control group (3.78 diopters) than in the atropine group (2.79 diopters) (P<.001). CONCLUSIONS: The data support the view that atropine therapy is associated with decreased progression of myopia and that beneficial effects remain after treatment has been discontinued.

Adolescent↗

Three-year maintenance of improved diet and physical activity: the CATCH cohort. Child and Adolescent Trial for Cardiovascular Health.

OBJECTIVE: To assess differences through grade 8 in diet, physical activity, and related health indicators of students who participated in the Child and Adolescent Trial for Cardiovascular Health (CATCH) school and family intervention from grades 3 through 5. DESIGN: Follow-up of the 4-center, randomized, controlled field trial with 56 intervention and 40 control elementary schools. PARTICIPANTS: We studied 3714 (73%) of the initial CATCH cohort of 5106 students from ethnically diverse backgrounds in California, Louisiana, Minnesota, and Texas at grades 6, 7, and 8. RESULTS: Self-reported daily energy intake from fat at baseline was virtually identical in the control (32.7%) and intervention (32.6%) groups. At grade 5, the intake for controls remained at 32.2%, while the intake for the intervention group declined to 30.3% (P<.001). At grade 8, the between-group differential was maintained (31.6% vs 30.6%, P = .01). Intervention students maintained significantly higher self-reported daily vigorous activity than control students (P = .001), although the difference declined from 13.6 minutes in grade 5 to 11.2, 10.8, and 8.8 minutes in grades 6, 7, and 8, respectively. Significant differences in favor of the intervention students also persisted at grade 8 for dietary knowledge and dietary intentions, but not for social support for physical activity. No impact on smoking behavior or stages of contemplating smoking was detected at grade 8. No significant differences were noted among physiologic indicators of body mass index, blood pressure, or serum lipid and cholesterol levels. CONCLUSION: The original CATCH results demonstrated that school-level interventions could modify school lunch and school physical education programs as well as influence student behaviors. This 3-year follow-up without further intervention suggests that the behavioral changes initiated during the elementary school years persisted to early adolescence for self-reported dietary and physical activity behaviors.

Adolescent↗

Secular trends of blood pressure and body size in a multi-ethnic adolescent population: 1986 to 1996.

OBJECTIVES: To determine the levels and time trends of blood pressure and body size in a healthy population of youth. STUDY DESIGN: Minneapolis, Minnesota, fifth through eighth grade public school children (aged 10 to 14 years) were surveyed in 1986 and 1996. Blood pressure, height, and weight were measured by technicians trained to the same rigorous protocol at each time period, and comparisons were made between the 2 groups (1986 and 1996). RESULTS: In 1986 and 1996, 8222 and 10,241 children, respectively, were measured with participation rates of over 93%. African American, Hispanic, Native American, Asian, and non-Hispanic white groups were all represented. Systolic blood pressure was significantly higher and diastolic blood pressure lower in 1996 than in 1986 in all ethnic and gender groups. Weight and body mass index (wt/ht2) were significantly higher in all groups in 1996. Adjustment for body size largely eliminated the systolic blood pressure differences but had no effect on measured diastolic blood pressure. CONCLUSIONS: Body size and systolic blood pressure are rising among school children. Weight and body mass index show substantial increases over 10 years (1986-1996). Diastolic blood pressure fell for unclear reasons. These changes may have future health implications for cardiovascular disease, as these youth move into adulthood.

Adolescent↗

How physically active are American children and what can we do about it?

Any discussion of obesity in youth must consider physical activity level or energy output. Many suggest that increasing levels of obesity among children is the direct result of declining levels of physical activity. There is accumulating evidence that physical activity among youth has declined over the past several decades. Less time is spent on physical education classes in school and many popular activities among youth such as television and computer games, involve minimal physical exertion. These observations are confirmed by studies of physical fitness and endurance. These measures have also declined among youth. Much has been learned about the factors associated with physical activity among youth. These factors were used to develop several innovative school-based programs which demonstrate increased physical activity and performance. Recommendations are made for increasing physical activity both in the school curriculum and outside the school day. Potential health benefits and likely effects on obesity are substantial.

Adolescent↗

HMO membership and patient age and the use of specialty care for hospitalized patients with acute stroke: The Minnesota Stroke Survey.

BACKGROUND: The number of older patients enrolling in health maintenance organizations (HMOs) is increasing. Concerns have been raised that older patients may be targeted by HMOs for more stringent cost-containment mechanisms, including reduced access to expensive specialty care. OBJECTIVES: We investigated the relationship between membership in an HMO and the decision to consult with a neurologist or admit to a neurology ward for patients hospitalized with acute stroke. We then compared 1-year mortality of patients who received neurology care to the 1-year mortality of those who did not receive neurology care. DESIGN: Retrospective medical record review. SUBJECTS: A sample of hospitalized acute stroke patients (age range, 30-79 years) who were discharged from Minneapolis-St. Paul metropolitan hospitals with a diagnosis code of acute cerebrovascular disease from 1991 to 1993. MEASURES: Trained nurses abstracted the medical records. Stroke events (n = 2,320) were validated using clinical criteria and neuroimaging reports. Mortality data were obtained from the Minnesota Death Index. RESULTS: Among patients enrolled in HMOs, 30% of validated stroke patients did not receive neurology care in comparison with 19% of patients not enrolled in HMOs. After adjusting for patient mix and hospital characteristics, the odds of receiving neurology care were half as great for patients enrolled in HMOs as compared with patients not enrolled in HMOs (odds ratio [OR] = 0.52, 95% confidence interval [CI] 0.36-0.74). The association of membership in HMOs with lower use of neurology care was concentrated in older patients. Within each age group, the odds ratios and 95% CI of receiving neurology care for patients enrolled in HMOs versus patients not enrolled in HMOs were: < 55 years (1.06, 0.42-2.67), 55 to 64 years (0.54, 0.34-0.87), 65 to 74 years (0.51, 0.36-0.71), and >75 years (0.40, 0.24-0.68). Using Cox regression, 30-day mortality did not differ between patients who received neurology care and those who did not. Among 30-day survivors, the mortality hazards ratio (HR) during the next 11 months for patients who received neurology care was 71% of the hazard for patients who did not receive neurology care (HR = 0.71, 95% CI = 0.55-0.91). CONCLUSIONS: These data suggest that membership in an HMO was associated with reduced access to neurology care for older patients with acute stroke and that patients who received neurology care had a lower risk of death during the year after their stroke. It remains to be determined if these differences in outcome are caused by true differences in stroke management or by unmeasured characteristics.

Acute Disease↗

Differences in the treatment of acute myocardial infarction between regions of countries and the impact on prognosis.

Differences in the incidence, prevalence of and mortality from coronary heart disease (CHD) are observed between and within countries. These differences are believed to be related to differing levels of CHD risk factors and medical care. Medical care for acute myocardial infarction has changed significantly in the past decades, with the development of new methods for diagnosis and treatment. Although widely known, these technologies are not consistently applied for reasons of availability and cost, as well as local medical cultures and traditions. The outcomes of medical care for acute myocardial infarction are best measured by case fatality of those hospitalized. Since the early 1960s, case fatality has fallen to less than half that observed previously. This has occurred in the context of widespread use of coronary care unit monitoring, innovative pharmacologic agents and invasive reperfusion treatments. A common debate compares aggressive invasive management with more conservative pharmacologic methods. In this context, studies have produced mixed results with no clear advantage to one approach when both methods are available and effectively applied to appropriately selected patients.

Angioplasty, Balloon, Coronary↗

Delayed hospital arrival for acute stroke: the Minnesota Stroke Survey.

BACKGROUND: Although recent advances have been made in the treatment of acute stroke, patients often arrive at the hospital too late to receive the maximum benefit from these new therapies. OBJECTIVE: To investigate characteristics that influence the time from symptom onset to hospital arrival (delay time) for patients with acute stroke. DESIGN: Retrospective medical record review. SETTING: Minneapolis-St. Paul metropolitan hospitals. PATIENTS: A 50% random sample of all patients 30 to 79 years of age who were hospitalized with acute stroke from 1991 to 1993. MEASUREMENTS: Patients were identified through discharge diagnosis lists by using the International Classification of Diseases, 9th Revision. Trained nurses abstracted the medical records. Stroke events were validated by using neuroimaging reports and additional clinical criteria (1895 patients). An accelerated failure time model was used to identify patient characteristics that independently predicted delay time. For 70% of patients (n = 1334), delay time was calculated from the medical record by subtracting the recorded time of symptom onset from the admission time. For the remaining 30% of patients (n = 561), the time of symptom onset was not recorded, and an approximate delay time was estimated from all available information. RESULTS: Among patients with a calculated delay time, half arrived within 3 hours of symptom onset and 90% arrived within 24 hours. Patients with approximated delay times tended to have longer delays, and less than 40% of these patients arrived within 24 hours of symptom onset. Some characteristics associated (P < 0.05) with longer delay included Asian/Pacific Islander ethnicity, dependence in any activities of daily living before stroke, and several symptoms at stroke onset. Characteristics associated (P < 0.05) with shorter delay included admission through the emergency department, presence of syncope or seizures at stroke onset, previous myocardial infarction, abnormal mental status, and greater disability at presentation (measured by the Rankin scale). CONCLUSIONS: Most patients arrive at the hospital too late to receive the maximum benefit from emerging stroke therapies. Efforts to reduce delays in hospital arrival after acute stroke can maximize the effectiveness of these therapies by specifically targeting persons at risk for longer delay.

Activities of Daily Living↗

Validation of death certificate diagnosis of out-of-hospital sudden cardiac death.

The validity of death certificate diagnosis of out-of-hospital sudden cardiac death (OOH-SCD) was studied among 108,676 30- to 74-year-old residents in 5 Minnesota communities using 6-year mortality data (1985 to 1990). Among 4,244 total deaths, location of death was listed on the certificate as out of hospital in 2,035 cases. Of those, 911 were judged not to have OOH-SCD because they had actually been admitted to the hospital or were noncardiovascular deaths. Among the remaining 1,124, 254 were diagnosed as OOH-SCD using a thorough, physician-based procedure that used clinical records, autopsy reports, and an informant (next-of-kin) interview. We used only death certificate information to define OOH-SCD simply and inexpensively as ICD-9 code 427.5 (cardiac arrest) plus location of death listed as out-of-hospital. Compared with the physician diagnosis, sensitivity was only 24%, whereas specificity was 85%. When the definition of OOH-SCD was expanded to include ICD codes 410-414 (acute myocardial infarction and chronic coronary artery disease), sensitivity improved to 87%, whereas specificity became 66%. However, even with this higher sensitivity and specificity, only 27% of the cases labeled OOH-SCD by death certificate agreed with the physician diagnosis. Death certificate diagnosis of OOH-SCD included many erroneous cases, and may not have been suitable for study of etiologic factors, such as cardiac dysrhythmias. Death certificate diagnosis may be useful to assess population time trends in OOH-SCD, provided that misclassification (false-positive rate) remains constant over time.

Adult↗