Capsule Commentary on Wallston et al., Psychometric Properties of the Brief Health Literacy Screen in Clinical Practice

Abstract

The patient’s degree of health literacy is emerging as important for clinicians to understand and address. However, health literacy has mostly been studied for research purposes and the instruments administered by trained research assistants. Wallston et al.1 examined the psychometric properties of the Brief Health Literacy Screen (BHLS) as a nurse-administered tool to measure health literacy among adults in both inpatient and primary care populations compared to administration by a research assistant (RA). In addition, RA’s administered a reference measure, the short Test of Functional Health Literacy in Adults (S-TOFHLA). The authors found evidence of inter-rater reliability between the nurse and research assistant measures of the BHLS in both samples. They also found that the BHLS was a significant predictor of the S-TOFHLA after adjustment for several demographic factors. The authors conclude that the BHLS, when administered by nurses during routine clinical care, is a valid and reliable measure of health literacy. As noted by the authors, the BHLS has been validated as a RA-administered measure of health literacy in several populations and settings.2,3 These study extended this results by demonstrating the validity of the instrument when administered by nurses in the course of routine clinical care across two settings—inpatient and primary care. However, it should be noted that the performance of the nurse-administered measurement differed significantly from that administered by the RAs, a difference reflected in the mediocre intra-class correlation between the two scores from the inpatient sample (ICC = 0.49). Also, validation analyses showed that the association between the RA-administered BHLS and the S-TOFHLA tended to be stronger than that of the nurse-administered BHLS and the S-TOFHLA, although the authors did not formally test this difference. Nevertheless, there are important implications of a portable, psychometrically sound measurement of health literacy that can by woven into routine clinical care. The next task for future research efforts is to assess how this screening tool can used to change clinical practice. What different approaches could be adopted for patients with different scores on this screening measure? How might these changes impact health literacy knowledge, health care outcomes and patient satisfaction? Addressing these questions might help us mediate the morbidity and cost associated with poor health literacy.4,5