In the social sciences, scaling is the process of measuring or ordering entities with respect to quantitative attributes or traits.
For example, a scaling technique might involve estimating individuals' levels of extraversion, or the perceived quality of products.
The word scale, including in academic literature, is sometimes used to refer to another composite measure, that of an index.
In most practical situations, multi-item scales are more effective in predicting outcomes compared to single items.
The use of single-item measures in research is advised cautiously, their use should be limited to specific circumstances.
[7][8] Table: Criteria for Assessing the Potential Use of Single-Item Measures[8] The type of information collected can influence scale construction.
Indexes are similar to scales except multiple indicators of a variable are combined into a single measure.