“Four-year-olds use several strategies to seriate multiple objects. Early emerging strategies include sorting objects based on irrelevant features (eg, colors), stringing together pairs of small and large objects, and identifying end points but failing to seriate intermediate objects,” the authors wrote.
Knowledge of Magnitude
Knowledge of magnitude, or being able to understand relations of objects given a specific dimension (such as size or brightness), may be the most relevant skill necessary for rating one’s pain on a pain intensity scale.
While many children around the age of 2 years can verbally produce magnitude labels for size and numbers, and many children around age 4 can correctly use the terms “more” and “less,” many children younger than age 5 have difficulty comparing and labeling more than 2 or 3 objects at a time.
“In general, 2- and 3-year-olds are able to identify the terminals (biggest/smallest) of a series, and when the context is familiar (eg, in matching the size of shoes to self, mother, and father), their performance suggests the emergence of a ‘medium’ principle,” the authors wrote.
When the context is unfamiliar (such as a scale of pain), identifying inner positions, such as the next smallest or medium, remains difficult for young children. “In fact, many 4-year-olds have a bias toward selecting the end points when asked to estimate the position of a number on a number line, whereas 6-year-olds are able to use the entire line for quantity estimation,” the authors note. “These results align with the finding that many 3-year-olds often fail to use the intermediate levels of a pain scale when using a 6-point scale.”
Using a pain scale requires understanding the meaning of symbols, such as poker chips or pictures of faces. In order to do this, children must be able to mentally represent and maintain information about both the symbols and their relation to pain intensity.
This is challenging for 2- and 3-year-olds because symbols are both physical objects as well as representations of “pieces of hurt.”
“Thus, treating objects on pain scales as symbols representing pain intensity may not be intuitive for children 2 to 3 years of age,” the authors wrote.