Abstract：
:Although randomized controlled trials are regarded as the gold standard for comparison of treatments, evidence from observational studies is still relevant. To cope with the problem of possible confounding in these studies, investigators need methods for analyzing their results which adjust for confounders and lead to unbiased estimation of the treatment effect. In this paper, the authors describe the main principles of three statistical methods for doing this. The first method is the classical approach of a multiple regression model including the effects of treatment and covariates. This considers the relation between prognostic factors and the outcome variable as a relevant criterion for adjustment. The second method is based on the propensity score, focusing on the relation between prognostic factors and treatment assignment. The third method is an ecologic approach using a grouped treatment variable, which may aid in avoiding confounding by indication. These approaches are applied to a partially randomized trial conducted in 720 German breast cancer patients between 1984 and 1997. The study had a comprehensive cohort study design that included recruitment of patients who had consented to participation but not to randomization because of a preference for one of the treatments. This design offers a unique opportunity to contrast results from the nonrandomized portion of a study with those for a randomized subcohort as a reference.
journal_name
Am J Epidemioljournal_title
American journal of epidemiologyauthors
Schmoor C,Caputo A,Schumacher Mdoi
10.1093/aje/kwn010subject
Has Abstractpub_date
2008-05-01 00:00:00pages
1120-9issue
9eissn
0002-9262issn
1476-6256pii
kwn010journal_volume
167pub_type
杂志文章abstract：:The determinants of individuals changes in gamma-glutamyltransferase (GGT) were examined in 1,171 males and 1,267 females in Tromsø, Norway, according to a 7-year longitudinal design. The basis for the study was two comprehensive population surveys in 1979-1980 and 1986-1987. In both sexes, increase in GGT displayed a...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a117075
更新日期：1994-04-15 00:00:00
abstract：:Associations of prenatal exposure to perfluoroalkyl substances (PFAS), ubiquitous chemicals used in stain- and water-resistant products, with adverse birth outcomes may be confounded by pregnancy hemodynamics. We measured plasma concentrations of 4 PFAS in early pregnancy (median length of gestation, 9 weeks) among 1,...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwx332
更新日期：2018-04-01 00:00:00
abstract：:Does a rise in crime result in increased sitting time and a reduction in physical activity? We used unobserved ("fixed")-effects models to examine associations between change in objectively measured crime (nondomestic violence, malicious damage, breaking and entering, and stealing, theft, and robbery) in Australia and...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kww106
更新日期：2016-12-15 00:00:00
abstract：:Decline in cognitive function in the elderly is common and represents a major clinical and public health concern. Aspirin may reduce the decline in cognitive function by influencing multi-infarct dementia, but data are sparse. The East Boston Senior Health Project is a population-based cohort study that enrolled 3,809...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a008801
更新日期：1996-04-01 00:00:00
abstract：:Two six-month randomized, controlled double-blind trials of the efficacy of virucidal nasal tissues in the prevention of natural colds were conducted in Charlottesville, Virginia, between 1983 and 1986. Tissues impregnated with malic and citric acids and sodium lauryl sulfate were used in both trials. Placebo tissues ...
journal_title：American journal of epidemiology
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1093/oxfordjournals.aje.a115059
更新日期：1988-11-01 00:00:00
abstract：:Diabetes confers a higher risk of cardiovascular disease on women than on men. The reasons for these sex differences, such as poorer cardiovascular risk factor profiles, have received considerable attention. However, a recent report on sex × diabetes interactions on cardiovascular disease identified that few if any pr...
journal_title：American journal of epidemiology
pub_type： 评论,杂志文章
doi：10.1093/aje/kwx327
更新日期：2018-03-01 00:00:00
abstract：:A prospective cohort study was used to quantify risk factors for sports concussions. Analysis was based on a stratified cluster sample of North Carolina high school athletes followed during 1996-1999. Clustering was by school and sport, and the sample included 15,802 athletes with 1-8 seasons of follow-up per athlete....
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwh304
更新日期：2004-11-15 00:00:00
abstract：:Decreased heart rate variability has been associated with an adverse prognosis in patients after myocardial infarction. Studies carried out in the population at large show contradictory results. The authors examined the association between heart rate variability on a standard 10-second electrocardiogram and cardiac an...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a009959
更新日期：1999-12-15 00:00:00
abstract：:This paper introduces the projection methods for describing and testing the differences between pairs of continuous distributions. These methods include the projection plot, the projection spline, and the iter-1 test. The projection plot displays the difference between corresponding quantiles against the average of th...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a009234
更新日期：1997-12-15 00:00:00
abstract：:Risk factors for fibroadenoma were examined in a case-control study involving 117 fibroadenoma cases ascertained by a major private pathology laboratory in Adelaide, Australia, between January 1983 and October 1985. For each case a population control was randomly selected from the electoral roll in Adelaide and matche...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a116278
更新日期：1992-02-01 00:00:00
abstract：:Cytomegalovirus (CMV) is a common worldwide perinatal infection. Although usually asymptomatic, it may cause deafness in up to 15% of these infants. A cross-sectional study was performed to determine the age-specific prevalence of CMV seropositivity in Chinese children and to determine if any risk factors for infectio...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a115467
更新日期：1990-01-01 00:00:00
abstract：:George W. Comstock (1915-2007), MD, MPH, DrPH, was lecturer and then professor of epidemiology at the Johns Hopkins University School of Hygiene and Public Health from 1956 to 2007 and served as editor-in-chief of the American Journal of Epidemiology from 1979 to 1988. This interview of George W. Comstock took place i...
journal_title：American journal of epidemiology
pub_type： 传,历史文章,面试
doi：10.1093/aje/kwt027
更新日期：2013-04-01 00:00:00
abstract：:Racial differences in the incidence and natural history of insulin-dependent diabetes mellitus were evaluated in Allegheny County, Pennsylvania. The yearly incidence rate for whites was approximately 1.5 times that for blacks. The cumulative risk of developing insulin-dependent diabetes prior to age 20 was greater for...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a114279
更新日期：1986-04-01 00:00:00
abstract：:Menstrual bleeding patterns are considered relevant indicators of reproductive health, though few studies have evaluated patterns among regularly menstruating premenopausal women. The authors evaluated self-reported bleeding patterns, incidence of spotting, and associations with reproductive hormones among 201 women i...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwr356
更新日期：2012-03-15 00:00:00
abstract：:Recent developments in population mathematics apply to measurement issues in epidemiology. In particular, they demonstrate explicitly the relations that prevail among incidence, prevalence, case-fatality, mortality, and duration of illness in a population at a moment in time, rather than in a cohort of persons followe...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/126.2.336
更新日期：1987-08-01 00:00:00
abstract：:Periconceptional intake of folic acid prevents some neural tube defects (NTDs). Other nutrients may also contribute to NTD etiologies; a likely candidate is choline. Similar to folic acid, choline is involved in one-carbon metabolism for methylation of homocysteine to methionine. The authors investigated whether mater...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwh187
更新日期：2004-07-15 00:00:00
abstract：:The authors examined the incidence of second primary cancers occurring after cervical and anal cancer. Data from the Connecticut Tumor Registry for 1935-1988 and eight other US tumor registries for 1973-1988 were used. Women with primary invasive cervical cancer had a relative risk of 4.6 (95% confidence interval (CI)...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a116420
更新日期：1992-07-01 00:00:00
abstract：:Coronary heart disease is the leading cause of mortality among persons with diabetes mellitus, but the factors that account for this high coronary heart disease mortality remain unclear. In the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study, conducted from 1982 to 1984, 92 deaths from...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a115834
更新日期：1991-06-15 00:00:00
abstract：:In the mid-19th century, the German hygienist Max von Pettenkofer viewed cholera as resulting from the interaction between a postulated cholera germ and the characteristics of soils. In order to cause cholera, the cholera germ had to become a cholera miasma, but this transformation required prolonged contact of the ge...
journal_title：American journal of epidemiology
pub_type： 传,历史文章,杂志文章
doi：10.1093/aje/kwm279
更新日期：2007-12-01 00:00:00
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journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a116992
更新日期：1994-02-01 00:00:00
abstract：:Male drivers sustained relatively more serious motorcycle collision injuries than did male passengers, female drivers, or female passengers. For male drivers, severity of injury was related to age. The relative frequency of serious head injury was highest for drivers not wearing helmets who were involved in collisions...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a112137
更新日期：1975-07-01 00:00:00
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journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/154.10.883
更新日期：2001-11-15 00:00:00
abstract：:The literature concerning social capital and health has grown exponentially during the past somewhat more than 10 years. The study by Kouvonen et al. (Am J Epidemiol 2008;167:1143-1151) is a longitudinal multilevel analysis of 33,577 public sector employees in Finland. The study shows a significant association between...
journal_title：American journal of epidemiology
pub_type： 评论,杂志文章
doi：10.1093/aje/kwn070
更新日期：2008-05-15 00:00:00
abstract：:The authors examined the independent and combined associations of physical activity and obesity with incident type 2 diabetes among 675,496 Korean men from the database of the National Health Insurance Corporation. During an average follow-up of 7.5 years (1996-2005), 52,995 men developed type 2 diabetes. Men with ove...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwr471
更新日期：2012-07-01 00:00:00
abstract：:Lower intake of the essential trace element selenium may be a risk factor for prostate cancer and other cancers. In the United States, many racial disparities in cancer incidence, such as the 61% higher incidence of prostate cancer among Blacks relative to Whites, remain unexplained. Using data from a large, nationall...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwm075
更新日期：2007-08-01 00:00:00
abstract：:In this paper, the authors report on the design of a population-based case-control study of family history as a risk factor for coronary heart disease (CHD). They studied the characteristics of subjects who completed a detailed family history questionnaire in 1992-1994 as well as the accuracy of recall of family histo...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a009410
更新日期：1998-06-15 00:00:00
abstract：:Among the major sources of indoor air pollution are combustion by-products from heating and cooking. Concern is increasing that use of polluting heating and cooking sources can increase cancer risk. In Canada, most cooking and heating currently relies on electricity or natural gas, but, in the past, and still in some ...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwk117
更新日期：2007-03-15 00:00:00
abstract：:The authors investigated timing and trajectories of fetal growth in relation to childhood development in the National Institute of Child Health and Human Development-Scandinavian Study of Successive Small-for-Gestational Age Births (1986-1988) (n = 1,059). Fetal size was assessed by ultrasound at 17, 25, and 33 gestat...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/aje/kwp296
更新日期：2009-12-01 00:00:00
abstract：:The possible relation between the occurrence of brain tumors in children and exposure to electric blankets or electrically heated water beds was investigated in a multicenter, population-based case-control study conducted on the West Coast of the United States. Information on maternal exposure during pregnancy or dire...
journal_title：American journal of epidemiology
pub_type： 杂志文章,多中心研究
doi：10.1093/oxfordjournals.aje.a008688
更新日期：1996-06-01 00:00:00
abstract：:Personnel assigned to infantry units of the army of the Republic of China (Taiwan) stationed in the Pescadores Islands experienced the highest incidence rate of scrub typhus (4%) and the highest rate of Rickettsia tsutsugamushi infection (12%) of the units studied during 1976. The ratio of scrub typhus to infection wi...
journal_title：American journal of epidemiology
pub_type： 杂志文章
doi：10.1093/oxfordjournals.aje.a112448
更新日期：1977-08-01 00:00:00
