Biomaterial Database

Selecting control groups for studies of familial aggregation of disease. 1995

P J Wickramaratne

Department of Psychiatry, College of Physicians and Surgeons, New York, NY 10032, USA.

In genetic-epidemiologic studies to determine the association between the disease status of family members, this association is measured by comparing rates of the disease in relatives of probands (index cases) with the disease, with the rates of the disease among individuals in a control group. Either of two types of control groups are generally used: (1) a control group consisting of a random sample from the population or the entire population if available or (2) a control group consisting of relatives of individuals without the disease under study. We examine the advantages and disadvantages of using these different types of control groups. We show two major results for family studies: (1) when there are no other factors associated with the disease status of an individual other than the disease status of a family member, both types of control groups will give a valid test of the null hypothesis of no familial aggregation. However, tests using a population control group will always be less efficient statistically, than those performed with a control group of relatives of probands without the disease under study, the degree of efficiency decreasing with increasing population prevalence of the disease. (2) When factors other than the disease status of a family member are also associated with the disease status of an individual, if this factor is a proband characteristic (which is not shared by relatives) population control groups cannot be adjusted to eliminate possible bias due to the potential confounding effect of this factor (unlike control groups consisting of relatives of probands without the disorder).

UI	MeSH Term	Description	Entries
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D015233	Models, Statistical	Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.	Probabilistic Models,Statistical Models,Two-Parameter Models,Model, Statistical,Models, Binomial,Models, Polynomial,Statistical Model,Binomial Model,Binomial Models,Model, Binomial,Model, Polynomial,Model, Probabilistic,Model, Two-Parameter,Models, Probabilistic,Models, Two-Parameter,Polynomial Model,Polynomial Models,Probabilistic Model,Two Parameter Models,Two-Parameter Model
D015331	Cohort Studies	Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.	Birth Cohort Studies,Birth Cohort Study,Closed Cohort Studies,Cohort Analysis,Concurrent Studies,Historical Cohort Studies,Incidence Studies,Analysis, Cohort,Cohort Studies, Closed,Cohort Studies, Historical,Studies, Closed Cohort,Studies, Concurrent,Studies, Historical Cohort,Analyses, Cohort,Closed Cohort Study,Cohort Analyses,Cohort Studies, Birth,Cohort Study,Cohort Study, Birth,Cohort Study, Closed,Cohort Study, Historical,Concurrent Study,Historical Cohort Study,Incidence Study,Studies, Birth Cohort,Studies, Cohort,Studies, Incidence,Study, Birth Cohort,Study, Closed Cohort,Study, Cohort,Study, Concurrent,Study, Historical Cohort,Study, Incidence
D015981	Epidemiologic Factors	Events, characteristics, or other definable entities that have the potential to bring about a change in a health condition or other defined outcome.	Epidemiologic Determinants,Determinant, Epidemiologic,Determinants, Epidemiologic,Epidemiologic Determinant,Epidemiologic Factor,Factor, Epidemiologic,Factors, Epidemiologic
D015982	Bias	Any deviation of results or inferences from the truth, or processes leading to such deviation. Bias can result from several sources: one-sided or systematic variations in measurement from the true value (systematic error); flaws in study design; deviation of inferences, interpretations, or analyses based on flawed data or data collection; etc. There is no sense of prejudice or subjectivity implied in the assessment of bias under these conditions.	Aggregation Bias,Bias, Aggregation,Bias, Ecological,Bias, Statistical,Bias, Systematic,Ecological Bias,Outcome Measurement Errors,Statistical Bias,Systematic Bias,Bias, Epidemiologic,Biases,Biases, Ecological,Biases, Statistical,Ecological Biases,Ecological Fallacies,Ecological Fallacy,Epidemiologic Biases,Experimental Bias,Fallacies, Ecological,Fallacy, Ecological,Scientific Bias,Statistical Biases,Truncation Bias,Truncation Biases,Bias, Experimental,Bias, Scientific,Bias, Truncation,Biase, Epidemiologic,Biases, Epidemiologic,Biases, Truncation,Epidemiologic Biase,Error, Outcome Measurement,Errors, Outcome Measurement,Outcome Measurement Error
D015986	Confounding Factors, Epidemiologic	Factors that can cause or prevent the outcome of interest but are not intermediate variables of the factor(s) under investigation.	Confounding Factor, Epidemiologic,Confounding Factors, Epidemiological,Confounding Factors, Epidemiology,Confounding Variables,Confounding Variables, Epidemiologic,Confounding Variables, Epidemiological,Confounding Factor, Epidemiological,Confounding Factor, Epidemiology,Confounding Variable,Confounding Variable, Epidemiologic,Confounding Variable, Epidemiological,Epidemiologic Confounding Factor,Epidemiologic Confounding Factors,Epidemiologic Confounding Variable,Epidemiologic Confounding Variables,Epidemiological Confounding Factor,Epidemiological Confounding Factors,Epidemiological Confounding Variable,Epidemiological Confounding Variables,Epidemiology Confounding Factor,Epidemiology Confounding Factors,Variable, Confounding,Variable, Epidemiologic Confounding,Variable, Epidemiological Confounding,Variables, Confounding,Variables, Epidemiologic Confounding,Variables, Epidemiological Confounding
D016022	Case-Control Studies	Comparisons that start with the identification of persons with the disease or outcome of interest and a control (comparison, referent) group without the disease or outcome of interest. The relationship of an attribute is examined by comparing both groups with regard to the frequency or levels of outcome over time.	Case-Base Studies,Case-Comparison Studies,Case-Referent Studies,Matched Case-Control Studies,Nested Case-Control Studies,Case Control Studies,Case-Compeer Studies,Case-Referrent Studies,Case Base Studies,Case Comparison Studies,Case Control Study,Case Referent Studies,Case Referrent Studies,Case-Comparison Study,Case-Control Studies, Matched,Case-Control Studies, Nested,Case-Control Study,Case-Control Study, Matched,Case-Control Study, Nested,Case-Referent Study,Case-Referrent Study,Matched Case Control Studies,Matched Case-Control Study,Nested Case Control Studies,Nested Case-Control Study,Studies, Case Control,Studies, Case-Base,Studies, Case-Comparison,Studies, Case-Compeer,Studies, Case-Control,Studies, Case-Referent,Studies, Case-Referrent,Studies, Matched Case-Control,Studies, Nested Case-Control,Study, Case Control,Study, Case-Comparison,Study, Case-Control,Study, Case-Referent,Study, Case-Referrent,Study, Matched Case-Control,Study, Nested Case-Control
D030342	Genetic Diseases, Inborn	Diseases that are caused by genetic mutations present during embryo or fetal development, although they may be observed later in life. The mutations may be inherited from a parent's genome or they may be acquired in utero.	Hereditary Diseases,Genetic Diseases,Genetic Disorders,Hereditary Disease,Inborn Genetic Diseases,Single-Gene Defects,Defect, Single-Gene,Defects, Single-Gene,Disease, Genetic,Disease, Hereditary,Disease, Inborn Genetic,Diseases, Genetic,Diseases, Hereditary,Diseases, Inborn Genetic,Disorder, Genetic,Disorders, Genetic,Genetic Disease,Genetic Disease, Inborn,Genetic Disorder,Inborn Genetic Disease,Single Gene Defects,Single-Gene Defect