RESUMEN
OBJECTIVE: Ultrasound is widely regarded as an important adjunct to antenatal care (ANC) to guide practice and reduce perinatal mortality. We assessed the impact of ANC ultrasound use at health centres in resource-limited countries. DESIGN: Cluster randomised trial. SETTING: Clusters within five countries (Democratic Republic of Congo, Guatemala, Kenya, Pakistan, and Zambia) METHODS: Clusters were randomised to standard ANC or standard care plus two ultrasounds and referral for complications. The study trained providers in intervention clusters to perform basic obstetric ultrasounds. MAIN OUTCOME MEASURES: The primary outcome was a composite of maternal mortality, maternal near-miss mortality, stillbirth, and neonatal mortality. RESULTS: During the 24-month trial, 28 intervention and 28 control clusters had 24 263 and 23 160 births, respectively; 78% in the intervention clusters received at least one study ultrasound; 60% received two. The prevalence of conditions noted including twins, placenta previa, and abnormal lie was within expected ranges. 9% were referred for an ultrasound-diagnosed condition, and 71% attended the referral. The ANC (RR 1.0 95% CI 1.00, 1.01) and hospital delivery rates for complicated pregnancies (RR 1.03 95% CI 0.89, 1.20) did not differ between intervention and control clusters nor did the composite outcome (RR 1.09 95% CI 0.97, 1.23) or its individual components. CONCLUSIONS: Despite availability of ultrasound at ANC in the intervention clusters, neither ANC nor hospital delivery for complicated pregnancies increased. The composite outcome and the individual components were not reduced. TWEETABLE ABSTRACT: Antenatal care ultrasound did not improve a composite outcome that included maternal, fetal, and neonatal mortality.
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Servicios de Salud Materno-Infantil , Área sin Atención Médica , Atención Perinatal , Complicaciones del Embarazo/diagnóstico por imagen , Ultrasonografía Prenatal , Adolescente , Adulto , Análisis por Conglomerados , Países en Desarrollo , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Mortalidad Materna , Embarazo , Complicaciones del Embarazo/mortalidad , Adulto JovenRESUMEN
OBJECTIVE: We sought to classify causes of stillbirth for six low-middle-income countries using a prospectively defined algorithm. DESIGN: Prospective, observational study. SETTING: Communities in India, Pakistan, Guatemala, Democratic Republic of Congo, Zambia and Kenya. POPULATION: Pregnant women residing in defined study regions. METHODS: Basic data regarding conditions present during pregnancy and delivery were collected. Using these data, a computer-based hierarchal algorithm assigned cause of stillbirth. Causes included birth trauma, congenital anomaly, infection, asphyxia, and preterm birth, based on existing cause of death classifications and included contributing maternal conditions. MAIN OUTCOME MEASURES: Primary cause of stillbirth. RESULTS: Of 109 911 women who were enrolled and delivered (99% of those screened in pregnancy), 2847 had a stillbirth (a rate of 27.2 per 1000 births). Asphyxia was the cause of 46.6% of the stillbirths, followed by infection (20.8%), congenital anomalies (8.4%) and prematurity (6.6%). Among those caused by asphyxia, 38% had prolonged or obstructed labour, 19% antepartum haemorrhage and 18% pre-eclampsia/eclampsia. About two-thirds (67.4%) of the stillbirths did not have signs of maceration. CONCLUSIONS: Our algorithm determined cause of stillbirth from basic data obtained from lay-health providers. The major cause of stillbirth was fetal asphyxia associated with prolonged or obstructed labour, pre-eclampsia and antepartum haemorrhage. In the African sites, infection also was an important contributor to stillbirth. Using this algorithm, we documented cause of stillbirth and its trends to inform public health programs, using consistency, transparency, and comparability across time or regions with minimal burden on the healthcare system. TWEETABLE ABSTRACT: Major causes of stillbirth are asphyxia, pre-eclampsia and haemorrhage. Infections are important in Africa.
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Algoritmos , Sistema de Registros , Mortinato/epidemiología , África/epidemiología , Asia/epidemiología , Países en Desarrollo , Femenino , Salud Global , Guatemala/epidemiología , Humanos , Servicios de Salud Materno-Infantil , Embarazo , Complicaciones del Embarazo/epidemiología , Estudios ProspectivosRESUMEN
OBJECTIVE: To describe the causes of maternal death in a population-based cohort in six low- and middle-income countries using a standardised, hierarchical, algorithmic cause of death (COD) methodology. DESIGN: A population-based, prospective observational study. SETTING: Seven sites in six low- to middle-income countries including the Democratic Republic of the Congo (DRC), Guatemala, India (two sites), Kenya, Pakistan and Zambia. POPULATION: All deaths among pregnant women resident in the study sites from 2014 to December 2016. METHODS: For women who died, we used a standardised questionnaire to collect clinical data regarding maternal conditions present during pregnancy and delivery. These data were analysed using a computer-based algorithm to assign cause of maternal death based on the International Classification of Disease-Maternal Mortality system (trauma, termination of pregnancy-related, eclampsia, haemorrhage, pregnancy-related infection and medical conditions). We also compared the COD results to healthcare-provider-assigned maternal COD. MAIN OUTCOME MEASURES: Assigned causes of maternal mortality. RESULTS: Among 158 205 women, there were 221 maternal deaths. The most common algorithm-assigned maternal COD were obstetric haemorrhage (38.6%), pregnancy-related infection (26.4%) and pre-eclampsia/eclampsia (18.2%). Agreement between algorithm-assigned COD and COD assigned by healthcare providers ranged from 75% for haemorrhage to 25% for medical causes coincident to pregnancy. CONCLUSIONS: The major maternal COD in the Global Network sites were haemorrhage, pregnancy-related infection and pre-eclampsia/eclampsia. This system could allow public health programmes in low- and middle-income countries to generate transparent and comparable data for maternal COD across time or regions. TWEETABLE ABSTRACT: An algorithmic system for determining maternal cause of death in low-resource settings is described.
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Causas de Muerte , Salud Global/estadística & datos numéricos , Muerte Materna/clasificación , Complicaciones del Embarazo/mortalidad , Población Negra/estadística & datos numéricos , República Democrática del Congo/epidemiología , Países en Desarrollo , Femenino , Guatemala/epidemiología , Humanos , Renta , India/epidemiología , Kenia/epidemiología , Muerte Materna/etiología , Mortalidad Materna , Pakistán/epidemiología , Embarazo , Estudios Prospectivos , Sistema de Registros , Población Blanca/estadística & datos numéricos , Zambia/epidemiologíaRESUMEN
This study assessed the role of age, gender, and ethnicity in chart documentation of smoking by primary care providers. Clinic patients (n = 304) were asked their smoking status and medical records were reviewed. Twenty-nine percent of reviewed patients were smokers, 27.6% former smokers, and 43.1% nonsmokers. Providers were more likely to document smoking among males (OR = 4.6; 95% CI = 2.2-9.5), middle-aged patients (OR = 4.0; 95% CI = 1.4-11.0), and smokers (OR = 8.1; 95% CI = 4.1-16.0). Data revealed selective documentation of smoking in males and middle-aged patients by providers, suggesting gender and age bias in the recognition and documentation of this risky behavior. We conclude that providers should screen for smoking in all patients regardless of age or gender.
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Fumar/epidemiología , Adulto , Distribución por Edad , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos/epidemiología , Oportunidad Relativa , Factores de Riesgo , Distribución por Sexo , Fumar/etnologíaRESUMEN
OBJECTIVE: Health care financing is changing rapidly in the United States. We investigated whether and how health care access is changing concurrently with changes in financing, with special attention to a minority population. METHODS: We examined a longitudinal biracial (half African-American, half White) urban cohort of 3,565 individuals, aged 25-37 years old, in 1992-93 and again in 1995-96. We measured access by self-reported (1) health insurance status, (2) regular source of medical care, and (3) lack of care due to financial problems. RESULTS: In 1992-93, 30.3% of the cohort experienced at least one access barrier, with a decline to 26.8% in 1995-96 (P<.005). However, access improved more for Whites than for African Americans; and access improved for higher, but not for lower, income groups (7% improvement for high income, vs 2% deterioration for lower income, P<.01). In addition, there was an 11% to 19% absolute increase in individuals making co-payments for health care utilization across all race/sex groups, with African Americans having markedly higher proportions of cost-sharing. African-American, low income, and unemployed individuals reported more acute care, but fewer outpatient visits. Income and employment explained racial differences. CONCLUSION: While access has improved or stabilized for higher income groups, there is a widening gap according to income, accompanied by an acute care pattern for low income groups that may be both inadequate and cost inefficient.
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Negro o Afroamericano/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/tendencias , Renta , Población Blanca/estadística & datos numéricos , Adolescente , Adulto , Estudios de Cohortes , Femenino , Financiación Personal , Accesibilidad a los Servicios de Salud/economía , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Investigación sobre Servicios de Salud , Humanos , Renta/clasificación , Renta/estadística & datos numéricos , Cobertura del Seguro , Estudios Longitudinales , Masculino , Estudios Prospectivos , Estados Unidos , Población UrbanaRESUMEN
OBJECTIVES: To follow the 1995 birth cohort of infants, born in the State of Missouri, through their first birthday to: 1) examine their rates of visits to emergency departments (EDs), 2) identify predictors of any ED visit, 3) examine rates of nonurgent ED visits, and 4) identify predictors of nonurgent visits. METHODS: This was a retrospective population cohort study. Using deterministic linkage procedures, 2 databases at the Missouri Department of Health (DOH; (the patient abstract database and the birth registry database) were linked by DOH personnel. International Classification of Diseases, Ninth Revision-Clinical Modification codes for ED visits were classified as emergent, urgent, or nonurgent by 2 researchers. Eight newborn characteristics were chosen for analysis. Negative binomial regression was used to examine the rates and predictors of both total and nonurgent ED visits. RESULTS: There were 935 total ED visits and 153 nonurgent ED visits per 1000 infant years. The average number of visits was.94, with 59% of infants having no visits, 21% having 1 ED visit, and 20% having 2 or more visits. Factors associated with increases in both total and nonurgent ED visits were Medicaid, self-pay, black race, rural region, presence of birth defects, and a nursery stay of >2 days. Significant interactions were found between Medicaid and race and Medicaid and rural regions on rates of ED use and nonurgent use. The highest rate of ED use, 1.8 per person year, was seen in white, rural infants on Medicaid, and the lowest rate (.4 per person year) was seen in urban white infants not on Medicaid. The highest rates of nonurgent use,.3 per person year, were among urban and rural Medicaid infants of both races and among black infants on commercial insurance. The lowest nonurgent rate,.04 per person year, was seen in white urban infants on commercial insurance. CONCLUSION: Infants in the State of Missouri have high rates of ED visits. Nonurgent visits are only a small portion of ED visits and cannot explain large variations in ED usage. Increased ED use by Medicaid patients may reflect continuing difficulties in accessing primary care.
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Servicios de Salud del Niño/estadística & datos numéricos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Factores de Edad , Estudios de Cohortes , Humanos , Recién Nacido , Medicaid/estadística & datos numéricos , Registro Médico Coordinado , Registros Médicos Orientados a Problemas/estadística & datos numéricos , Medicare/estadística & datos numéricos , Missouri , Grupos Raciales , Sistema de Registros , Estudios RetrospectivosRESUMEN
BACKGROUND: In an effort to learn more about the smoking behavior of hospital employees, a study was conducted at the University of Kansas Medical Center (KUMC) regarding tobacco usage and secondhand smoke exposure. METHODS: An anonymous voluntary survey was distributed to 4177 full-time employees in Kansas City and Wichita during June and July of 1998. Questions included tobacco usage and exposure to secondhand smoke. The survey results were assimilated in a data base, which was analyzed in a variety of ways to arrive at several conclusive findings. RESULTS: Of the 1187 respondents (28. 4%), 35.1% had smoked at least 100 cigarettes in their life (41% of those had at least a 10 pack-year history), and 11.8% currently smoked. The groups with the highest percentage of current smokers were females (12%), blacks (17%), Kansas City campus employees (12%), and nonfaculty (13%). Sixty-seven percent of respondents were exposed to secondhand smoke in the previous week, and 25% were exposed at KUMC. CONCLUSIONS: After arriving at the results of this study, recommendations include starting an educational campaign against smoking, promoting cessation programs, moving the current smoking area to a less populated area on campus, and investigating a total campus ban on smoking.
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Centros Médicos Académicos , Personal de Hospital/estadística & datos numéricos , Fumar/epidemiología , Contaminación por Humo de Tabaco/estadística & datos numéricos , Adulto , Actitud Frente a la Salud , Escolaridad , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Kansas/epidemiología , Masculino , Persona de Mediana Edad , Evaluación de Necesidades , Ocupaciones/estadística & datos numéricos , Personal de Hospital/educación , Personal de Hospital/psicología , Grupos Raciales , Distribución por Sexo , Fumar/psicología , Encuestas y CuestionariosRESUMEN
Oxidative stress is thought to be an important pathogenic mechanism in many diseases of the retina. The purpose of this study was to investigate the chemical changes that are present in the photoreceptor outer segments of the retina following exposure to oxidative stress. Fourier transform infrared (FT-IR) microspectroscopy enables the characterization and semi-quantitation of chemical functional groups in microscopic regions of tissue sections. This technique was used to evaluate the chemical changes in the outer segments following exposure to ferrous sulfate, which promotes oxidative tissue damage. A reduction of C=C-H and C=O functional groups was observed in the outer segments of iron-injected eyes compared to vehicle-injected eyes at 3 days following injection, which is prior to major histological changes that occur by 7 days. These functional groups are found in docosahexaenoic acid (DHA), which is present at a high concentration in the outer segments. DHA contains a series of six cis-conjugated double bonds, which are vulnerable to free radical attack, and the reduction of these unsaturation group absorptions suggests that DHA was degraded and/or removed from the outer segments. An unexpected finding was that several other chemical functional groups increased in concentration over time in the outer segments of vehicle-injected eyes compared to non-injected eyes. These increases generally did not include C=C-H or C=O, which suggests that either DHA was being degraded while other organic molecules were being concentrated, or that production of DHA failed to be upregulated in vehicle-injected eyes. In summary, there was a loss of both C=C-H and C=O functional group concentrations in the outer segments of iron-injected eyes, and there was an increased concentration of several other chemical functional groups following trauma induced by vehicle injection.
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Hierro/metabolismo , Estrés Oxidativo , Segmento Externo de la Célula en Bastón/metabolismo , Animales , Compuestos Ferrosos/administración & dosificación , Compuestos Ferrosos/metabolismo , Inyecciones , Hierro/administración & dosificación , Ratas , Ratas Long-Evans , Segmento Externo de la Célula en Bastón/ultraestructura , Cloruro de Sodio/administración & dosificación , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
Selection of surrogate endpoint biomarkers (SEBs) and appropriate study design are two of the main challenges in evaluating potential chemopreventive agents. In a prospective random fine-needle aspiration (FNA) study of women at high risk of development of breast cancer, we previously demonstrated that cytologic evidence of epithelial hyperplasia with or without atypia, as well as abnormalities of several cellular biomarkers (DNA ploidy; immunocytochemical expression of p53, EGFR, ER, and/or Her-2/neu), were more prevalent in high-risk women than in low-risk controls. We also demonstrated that the subsequent development of breast cancer was best predicted by an initial presentation of hyperplasia with atypia, as well as by multiple biomarker abnormalities. These findings indicate that FNA cytology and biomarkers can be used to identify women who are appropriate subjects for chemoprevention trials, and can then be used as surrogate endpoint biomarkers to monitor efficacy of potential agents. An example of this use in an ongoing single-agent phase II trial is provided. Several options for study design of possible multi-agent breast cancer chemoprevention trials are discussed, depending upon the existing preclinical and clinical data, the questions being asked, and the number of eligible subjects available.
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Biopsia con Aguja/métodos , Neoplasias de la Mama/prevención & control , Mama/patología , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/análisis , Mama/metabolismo , Neoplasias de la Mama/metabolismo , Protocolos Clínicos , Ensayos Clínicos como Asunto , Eflornitina/uso terapéutico , Receptores ErbB/metabolismo , Femenino , Humanos , Hiperplasia , Placebos , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
OBJECTIVE: We conducted this study to determine if a smoking status stamp would prompt physicians to increase the number of times they ask, advise, assist, and arrange follow-up for African-American patients about smoking-related issues. DESIGN: An intervention study with a posttest assessment (after the physician visit) conducted over four 1-month blocks. The control period was the first 2 weeks of each month, while the following 2 weeks served as the intervention period. SETTING: An adult walk-in clinic in a large inner-city hospital. PARTICIPANTS: We consecutively enrolled into the study 2,595 African-American patients (1,229 intervention and 1, 366 control subjects) seen by a housestaff physician. INTERVENTIONS: A smoking status stamp placed on clinic charts during the intervention period. MAIN RESULTS: Forty-five housestaff rotated through the clinic in 1-month blocks. In univariate analyses, patients were significantly more likely to be asked by their physicians if they smoke cigarettes during the intervention compared with the control period, 78.4% versus 45.6% (odds ratio [OR] 4.28; 95% confidence interval [CI] 3.58, 5.10). Patients were also more likely to be told by their physician to quit, 39.9% versus 26.9% (OR 1.81; 95% CI 1.36, 2.40), and have follow-up arranged, 12.3% versus 6.2% (OR 2.16; 95% CI 1.30, 3.38). CONCLUSIONS: The stamp had a significant effect on increasing rates of asking about cigarette smoking, telling patients to quit, and arranging follow-up for smoking cessation. However, the stamp did not improve the low rate at which physicians offered patients specific advice on how to quit or in setting a quit date.
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Negro o Afroamericano , Estado de Salud , Prevención del Hábito de Fumar , Adulto , Distribución de Chi-Cuadrado , Consejo , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Examen Físico , Relaciones Médico-Paciente , Cese del Hábito de Fumar , Población UrbanaRESUMEN
OBJECTIVE: To determine the effect of different bladder management methods on long-term renal function in persons with spinal cord injury (SCI). DESIGN: Cohort study. SETTING: Model SCI care system within a large teaching hospital. PATIENTS: Consecutive sample of 1,114 persons with SCI who were injured between 1969 and 1994. MAIN OUTCOME MEASURE: Total and individual kidney effective renal plasma flow (ERPF). RESULTS: ERPF was generally lower in persons with cervical injuries or kidneys that had a renal stone, older persons, and women. Overall, there was very little change in renal function as time postinjury increased, and there were no clinically meaningful differences in the change in renal function over time among persons using different bladder management methods. CONCLUSION: Renal function was adequately preserved in the great majority of persons and did not appear to be influenced to any great extent by method of bladder management.
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Flujo Plasmático Renal Efectivo , Traumatismos de la Médula Espinal/complicaciones , Vejiga Urinaria Neurogénica/fisiopatología , Vejiga Urinaria Neurogénica/rehabilitación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cistostomía , Femenino , Humanos , Lactante , Modelos Lineales , Cuidados a Largo Plazo , Masculino , Persona de Mediana Edad , Estimulación Física/métodos , Factores de Tiempo , Vejiga Urinaria Neurogénica/etiología , Cateterismo Urinario/métodos , Derivación UrinariaRESUMEN
OBJECTIVES: This study estimated the amount of weight change in a biracial cohort of young adults and the separate components attributable to time-related and aging-related changes, as well as identified possible determinants of weight change. METHODS: In this population-based prospective study of 18- to 30-year-old African-American and White men and women, body weight and prevalence of overweight were measured from 1985/86 to 1992/93. RESULTS: Average weight increased over the 7 years, increases ranging from 5.2 kg (SE = 0.2, n = 811) in White women to 8.5 kg (SE = 0.3, n = 882) in African-American women. Significant time-related increases in weight, ranging from 2.0 kg (SE = 1.0) in White women to 4.8 kg (SE = 1.0, n = 711) in African-American men, accounted for 40% to 60% of the average total weight gain. Aging-related increases were also significant, ranging from 2.6 kg (SE = 0.8, n = 944) in White men to 5.0 kg (SE = 1.1) in African-American women. The prevalence of overweight increased progressively in each group. Decreased physical fitness was most strongly associated with weight gain in both sexes. CONCLUSIONS: The observed dramatic time-related weight gains, most likely due to secular (period-related) trends, are a serious public health concern.
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Conducta , Negro o Afroamericano , Peso Corporal , Estilo de Vida , Población Blanca , Adolescente , Adulto , Envejecimiento/fisiología , Recolección de Datos , Femenino , Humanos , Masculino , Obesidad , Aptitud Física , Estudios Prospectivos , Aumento de PesoRESUMEN
Condylar position between centric occlusion (CO) and centric relation (CR) was compared for 24 adolescent orthodontic patients at pretreatment, posttreatment, and during the retention phase of orthodontic treatment. Models were mounted using a face-bow transfer and CR interocclusal registrations. Differences in CO-CR were then measured at the condylar level in the x, y, and z dimensions. The data were analyzed statistically to determine the mean CO-CR differences in the sample as well as the magnitude and direction of the CO-CR differences from one time period to the next. Results showed that the mean three-dimensional distance between CO and CR tended to increase from pretreatment to the retention phase for the right and left sides, the left side showing a greater increase. Intraexaminer variability accounted for 20% to 25% of the total variability when all possible sources of variability were considered. Correlation with a second examiner in recording CR was in the range of .61 and .75 for the right and left sides, respectively. Interexaminer variability was found to be similar to the variability associated with the CO-CR discrepancies over time. Consequently, the differences in measurements obtained could be the result of changes in the CO-CR relationship, examiner variability, or a combination of both.
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Relación Céntrica , Oclusión Dental Céntrica , Maloclusión/terapia , Ortodoncia Correctiva , Adolescente , Niño , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Variaciones Dependientes del Observador , Aparatos Ortodóncicos , Evaluación de Resultado en la Atención de Salud , Planificación de Atención al Paciente , Recurrencia , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
The present study was conducted to determine the effects of curve of Spee leveling on three-dimensional arch length and specific components of arch form. The mandibular pretreatment and posttreatment dental casts of 33 patients treated orthodontically without the extraction of teeth were digitized with a three-dimensional positioning transducer integrated with a graphics calculator. Statistical analysis was carried out with general linear models and the calculation of Pearson correlation coefficients of the relationships between the dependent variable of the curve of Spee leveling and the independent variables of arch length, arch depth, and three arch widths. The regression and correlation analyses essentially showed no relationship between the independent variables (arch length, arch depth, and the three arch widths) and the dependent variable (curve of Spee leveling). Although the three-dimensional arch length was increased after leveling of the curve of Spee in 24 of the 33 dental casts evaluated, the results from the statistical analyses indicated that this increased arch length was not necessarily the result of the curve of Spee leveling but may have been caused by other variables.
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Arco Dental/anatomía & histología , Oclusión Dental , Mandíbula/anatomía & histología , Ortodoncia , Gráficos por Computador , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Masculino , Maloclusión/patología , Maloclusión/terapia , Modelos Dentales/estadística & datos numéricos , Ortodoncia/estadística & datos numéricos , TransductoresRESUMEN
The purpose of the study presented here was to simultaneously measure air quality and respiratory function and symptoms in populations living in the neighborhood of waste incinerators and to estimate the contribution of incinerator emissions to the particulate air mass in these neighborhoods. We studied the residents of three communities having, respectively, a biomedical and a municipal incinerator, and a liquid hazardous waste-burning industrial furnace. We compared results with three matched-comparison communities. We did not detect differences in concentrations of particulate matter among any of the three pairs of study communities. Average fine particulate (PM2.5) concentrations measured for 35 days varied across study communities from 16 to 32 micrograms/m3. Within the same community, daily concentrations of fine particulates varied by as much as eightfold, from 10 to 80 micrograms/m3, and were nearly identical within each pair of communities. Direct measurements of air quality and estimates based on a chemical mass balance receptor model showed that incinerator emissions did not have a major or even a modest impact on routinely monitored air pollutants. A onetime baseline descriptive survey (n = 6963) did not reveal consistent community differences in the prevalence of chronic or acute respiratory symptoms between incinerator and comparison communities, nor did we see a difference in baseline lung function tests or in the average peak expiratory flow rate measured over a period of 35 days. Based on this analysis of the first year of our study, we conclude that we have no evidence to reject the null hypothesis of no acute or chronic respiratory effects associated with residence in any of the three incinerator communities.