An informant in a survey is someone asked to provide information about another person, persons, or an organization, for example, when a parent is interviewed about a young child who could not answer the survey questions. Informants (also known as proxies) tend to be used in surveys when the target respondent is unable to respond or when it is not feasible to collect responses from all members of a group under study. As the use of informants to collect quantitative data has become integral to survey research, due to the cost-effectiveness of the approach, so has the study of the effects of using informants on the data that are collected. The substitution of informants limits the types of data that can be collected with accuracy, ...