Conscientiousness
Measurement
Measurement
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A person's level of conscientiousness is generally assessed using self\-report measures, although peer\-reports and third\-party observation can also be used. Self\-report measures are either *lexical* or based on *statements*. Deciding which measure of either type to use in research is determined by an assessment of psychometric properties and the time and space constraints of the study being undertaken.

### Lexical

[*Lexical measures*](/wiki/Lexical_hypothesis "Lexical hypothesis") use adjectives that reflect conscientiousness traits, such as "efficient" and "systematic", and are very space\- and time\-efficient for research purposes. Goldberg developed a 20\-word measure as part of his 100\-word Big Five markers. Saucier developed a briefer 8\-word measure as part of his 40\-word mini\-markers. Thompson revised these measures to develop the International English Mini\-Markers which has superior validity and reliability in populations both within and outside North America. Internal consistency reliability of the International English Mini\-Markers for the Conscientiousness measure for native English\-speakers is reported as .90, that for non\-native English\-speakers is .86\.

### Statement

*Statement measures* tend to comprise more words than lexical measures, so consume more research instrument space and more respondent time to complete. Respondents are asked the extent to which they, for example, often forget to put things back in their proper place, or are careful to avoid making mistakes. Some statement\-based measures of conscientiousness have similarly acceptable psychometric properties in North American populations to lexical measures, but their generally [emic](/wiki/Emic_and_etic "Emic and etic") development makes them less suited to use in other populations. For instance, statements in colloquial North American English like *Often forget to put things back in their proper place* or *Am careful to avoid making mistakes* can be hard for non\-native English\-speakers to understand, suggesting internationally validated measures might be more appropriate for research conducted with non\-North Americans.


How might the use of lexical or statement-based measures influence research results?