Health Numeracy Measure

 

This project is funded by the National Cancer Institute through the Medical College of Wisconsin. The Project is run by Elizabeth Jacobs, MD.

General health literacy can be defined as a person’s ability to obtain, process, and understand the basic health information needed to make appropriate health care decisions. The Institute of Medicine has put forth a model of health literacy that includes four constructs: 1) cultural and conceptual knowledge; 2) oral literacy (listening and speaking); 3) print literacy (writing and reading); and 4) numeracy. Each construct reflects a set of skills required to function in the health care system and each requires a valid measure to move forward our understanding of the relationship between literacy and health.

The construct of numeracy reflects a person’s ability to use and interpret quantitative information in the context of their health care. Numeracy is of particular importance in the translation of evidence-based information to patients to support informed decision-making. A comprehensive and valid numeracy measure will advance the science of communication and patient educational materials, and support the development of interventions to improve health numeracy skills.

The specific aims are:
1) To develop a measure of health numeracy named the Numeracy Understanding in Medicine Instrument (NUMi). The instrument will be developed using item response theory and among a population that is diverse in race and ethnicity. The NUMi will include domains of basic mathematic skills, applied health numeracy skills, and conceptual health numeracy skills.
2) To establish the internal reliability and content, construct, and criterion validity of the NUMi.
3) To develop a version of the NUMi for Spanish-speaking persons. Differential item functioning will be used to determine whether items in the NUMi function similarly between the English and Spanish version.
A valid and theoretically based measure of health numeracy is needed to further research and clinical care in the area of health literacy. In this proposal, the justification for an instrument of health numeracy is established and methods for development and validation of the instrument are presented.