Previous research has also shown that health literacy and numeracy affect comprehension of information [ 29].
In Canada, data linkage of routinely-collected population level measures of numeracy, reading comprehension and writing skills with the EDI dataset was conducted [ 24].
Measures such as the Test of Functional Health Literacy in Adults (TOFHLA [ 23]) or its short form [ 24], the Rapid Estimate of Adult Literacy in Medicine [ 25], and the Newest Vital Sign [ 26] assess an individual's reading, numeracy, and comprehension skills in relation to healthcare.
Further research should explore how issues of language, literacy, or numeracy affect comprehension; if the nutrition label can increase awareness of a health-diet link; the role of the label and perceived costs of a 'healthy' diet; and what additional information should accompany the label to reach those with less access to health services and chronic disease management.
How numeracy influences risk comprehension and medical decision making.
The OHL-AQ comprises four sections: reading comprehension, numeracy, listening, and decision-making.
This is not surprising given that the majority of these earlier tools focus on numeracy and reading comprehension only.
Pearson's correlation coefficients between the oral health knowledge test and the reading comprehension, numeracy and total R-OHLI were 0.401, 0.258, and 0.363, respectively (p < 0.001).
Women, participants with a university degree, and those who visited a dentist at least once a year had significantly (p < 0.05) higher mean scores for each section (reading comprehension, numeracy) and for total R-OHLI compared to their counterparts.
Recently, the Health Literacy Measurement Scale (HeLMS) was developed to measure elements of health literacy beyond numeracy and reading comprehension and thereby overcome many of the perceived limitations of existing instruments [ 24].
