Description
Social and political scientists generally rely on composite scores, such as means or additive scores, to test whether groups (e.g., countries, cohorts, occupational groups) differ in some dimensions of interest. Differences (or lack of differences) in these scores are interpreted as reflecting ‘real’ group differences (or ‘real’ lack of differences). However, methodological artefacts, such as inaccurate translations or a tendency to respond towards the middle of the scale, have the potential to affect the measurement, which may result in biased findings (e.g., artificial mean differences).