Research conducted at Vanderbilt University Medical Center shows that routine administration of the Brief Health Literacy Screen (BHLS) by nurses provides a valid measure for large-scale studies of the influence of health literacy on clinical outcomes.
The BHLS poses three related questions to adult patients:
• How confident are you filling out medical forms by yourself?
• How often do you have someone help you read hospital materials?
• How often do you have problems learning about your medical condition because of difficulty understanding written information?
The screen uses a five-point response scale and takes a minute or less to administer. In previous studies it has been found effective in detecting low health literacy.
A new study of the BHLS, conducted by Sunil Kripalani, M.D., M.Sc., Ken Wallston, Ph.D., and colleagues is among the first to test the validity of a health literacy screen administered by nurses in routine inpatient and outpatient practice — as opposed to more controlled research contexts where health literacy assessments such as the BHLS have been administered exclusively by research assistants.
The study, which appeared in the Journal of General Internal Medicine, focused on 793 adult hospital patients and primary care clinic patients previously screened by nurses using the BHLS. Nurses at these Vanderbilt facilities routinely administer the screen as part of ongoing initiatives involving health literacy.
“Vanderbilt is the first medical center that is assessing on a large scale the extent to which the health care environment is challenging for patients to navigate, integrating this information into data repositories and using it for population-based studies of how these challenges affect patient care and outcomes. It’s part of a broader interest in studying social determinants of health, so that health care systems can continue to improve,” said Kripalani, associate professor of Medicine and director of the Effective Health Communication Core.
All 793 patients were rescreened by research assistants, once using the BHLS and once using a brief, validated reading comprehension test called the Shortened Test of Functional Health Literacy in Adults (S-TOFHLA).
The investigators looked at: rates of conflicting responses to the three BHLS questions (internal consistency); comparisons of BHLS results gathered by nurses and by research assistants (inter-administrator reliability); and comparisons of results from the S-TOFHLA and the BHLS (concurrent validity).
The nurse-administered BHLS passed the three-part test of reliability and validity. It also remained predictive of S-TOFHLA results after controlling for patient age, gender, race and education — in other words, the BHLS provided more information about patients’ health literacy than could be gleaned from these demographic factors alone.
“Limited health literacy is associated with difficulty understanding one’s health condition, less adherence to self-care behaviors, poorer health status, increased mortality and higher health care costs. Nevertheless, most health care providers are unaware of their patients’ health literacy,” the authors wrote.
“Measuring the health literacy skills of populations seeking care, and even those of individual patients, may enable health care facilities to improve care delivery.”
Ongoing Vanderbilt studies are examining the influence of low health literacy on clinical outcomes.
“Social factors are well-known to be critical determinants of individuals’ health, and better understanding how these factors can be used to improve health care delivery and health care outcomes is essential,” said Robert Dittus, M.D., MPH, associate vice chancellor for Public Health and Health Care and senior associate dean for Population Health Sciences.
The research was supported by National Institutes of Health grants HL096581, DK087894 and HL109019, and by the Vanderbilt Innovation and Discovery in Engineering and Science (IDEAS) Program.
