Assessment of single-item literacy questions, age, and education level in the prediction of low health numeracy.
OBJECTIVE
Determining a patient's health literacy is important to optimum patient care. Single-item questions exist for screening written health literacy. We sought to assess the predictive potential of three common screening questions, along with patient age and education level, in the prediction of low health numerical literacy (numeracy).


METHODS
After demographic and educational information was obtained, 441 patients were administered three health literacy screening questions. The three-item Schwartz-Woloshin Numeracy Scale was then administered to assess for low health numeracy (score of 0 out of 3). This score served as the reference standard for Receiver Operating Characteristics (ROC) curve analysis. ROC curves were constructed and used to determine the area under the curve (AUC); a higher AUC suggests increased statistical significance.


RESULTS
None of the three screening questions were significant predictors of low health numeracy. However, education level was a significant predictor of low health numeracy, with an AUC (95% CI) of 0.811 (0.720-0.902). This measure had a specificity of 95.3% at the cutoff of 12 years of education (<12 versus > or = 12 years of education) but was non-sensitive.


CONCLUSIONS
Common single-item questions used to screen for written health literacy are ineffective screening tools for health numeracy. However, low education level is a specific predictor of low health numeracy.
Wills Eye Institute, Philadelphia, Pennsylvania, USA.
Tim V
TV
Johnson
Ammara
A
Abbasi
Renee S
RS
Kleris
Samantha S
SS
Ehrlich
Echo
E
Barthwaite
Jennifer
J
DeLong
Viraj A
VA
Master
D004522:Educational Status; D005260:Female; D057220:Health Literacy; D006801:Humans; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D012372:ROC Curve; D011795:Surveys and Questionnaires