- In epidemiological and genetic research, the method by which a person, pedigree, or cluster is brought to the attention of an investigator; has a bearing on the interpretation of segregation ratios, concordance rates, linkage analysis, and other probability features.- complete a. method by which all families with at least one affected individual in a population are certain or have an equal chance of being identified by survey or an appropriate random sampling technique.- incomplete a. method of locating affected individuals in which probability of locating any specific patient has a known value between 0 and 1. SYN: truncate a..- single a. method of a. of locating affected individuals by hospital or clinic admission or another way in which probability of encountering the same family twice approaches zero; thus, the probability that a family will be ascertained is proportional to the number of affected members.- total a. method by which all members of a population at risk of a trait are discerned or equally likely to be contained in a sample thereof.- truncate a. SYN: incomplete a..
* * *as·cer·tain·ment (ă″sər-tānґmənt) in genetic studies, the method by which persons with a trait or disease are selected or found by an investigator.
Medical dictionary. 2011.