Any assessment procedure is subject to error. Error in measurement can arise because the instrument is inconsistent (poor reliability) or because the instrument does not measure what we think it is measuring (poor validity). Neighbors and Lumpkin (1990) questioned the assumption that the same construct is measured when instruments developed among non-Hispanic whites are applied to African-Americans or other minority ethnic groups.
At one level, differing idioms and colloquialisms can cause a translated instrument to have different meanings from those intended by the original developers. Even within ethnic groups, older persons who are recent immigrants may interpret items differently from older persons who have lived in the United States for some time.
At a more subtle level, some constructs vary so much across cultures as to be quite different or even irrelevant; depressive disorder, for example , has been identified by anthropologists and medical researchers for the heterogeneity of its expression across cultures (Kleinman, 1985; Kleinman, 1980).
Literacy and level of educational attainment may be important considerations in assessing all older adults, but especially older adults from ethnic minorities who historically have had less opportunity to advance in school such as many from Hispanic/Latino backgrounds. (See information on education in the section on Demographics.)
Closely tied to educational level attained is literacy, or the ability to understand and use written information. In clinical work, care should be taken to consider the educational level of patients who may not be used to the type of questions that are asked in many functional and cognitive tests.
In interpreting results from assessment, clinicians should be aware that the reliability and validity of instruments developed, for example, among urban hospitalized patients in the Northeastern United States may not be applicable to a border community in rural South Texas, even if both speak Spanish.