Limitations of the S-TOFHLA in measuring poor numeracy: a cross-sectional study

Ashley J Housten, Lisa M Lowenstein, Diana S Hoover, Viola B Leal, Geetanjali R Kamath, Robert J Volk, Ashley J Housten, Lisa M Lowenstein, Diana S Hoover, Viola B Leal, Geetanjali R Kamath, Robert J Volk

Abstract

Background: Although the Short Test of Functional Health Literacy in Adults (S-TOFHLA) is widely used, misidentification of individuals with low health literacy (HL) in specific HL dimensions, like numeracy, is a concern. We examined the degree to which individuals scored as "adequate" HL on the S-TOFHLA would be considered as having low HL by two additional numerical measures.

Methods: English-speaking adults aged 45-75 years were recruited from a large, urban academic medical center and a community foodbank in the United States. Participants completed the S-TOFHLA, the Subjective Numeracy Scale (SNS), and the Graphical Literacy Measure (GL), an objective measure of a person's ability to interpret numeric information presented graphically. Established cut-points or a median split classified participants and having high and low numeracy.

Results: Participants (n = 187), on average were: aged 58 years; 63% female; 70% Black/African American; and 45% had a high school degree or less. Of those who scored "adequate" on the S-TOFHLA, 50% scored low on the SNS and 40% scored low on GL. Correlation between the S-TOFHLA and the SNS Total was moderate (r = 0.22, n = 186, p = 0.01), while correlation between the S-TOFHLA and the GL Total was large (r = 0.53, n = 187, p ≤ 0.01).

Conclusions: Findings suggest that the S-TOFHLA may not capture an individuals' HL in the dimension of numeracy. Efforts are needed to develop more encompassing and practical strategies for identifying those with low HL for use in research and clinical practice.

Trial registration: NCT02151032 (retrospectively registered: May 30, 2014).

Keywords: Decision-making; Health disparities; Health literacy; Numeracy.

Conflict of interest statement

Ethics approval and consent to participate

The Institutional Review Board of The University of Texas MD Anderson Cancer Center approved this protocol and participant informed written consent process.

Consent for publication

Not applicable.

Competing interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Percentage of S-TOFHLA “Adequate” Participants who Scored in Lower 25th Percentile on Other HL Measures
Fig. 2
Fig. 2
Percentage of S-TOFHLA “Adequate” Participants who Scored Low on Other Health Literacy Measures

References

    1. US Department of Health and Human Services. Healthy people 2010. Washington, DC: US government printing office. Originally developed for Ratzan SC, Parker RM. introduction. In National Library of medicine current bibliographies in medicine: health literacy; 2000. Selden CR, Zorn M, Ratzan SC, Parker RM, eds. NLM pub. No. CBM 2000–1. Bethesda, MD: National Institutes of Health, U.S: Department of Health and Human Services; 2000.
    1. Institute of Medicine . Health literacy: a prescription to end confusion. Washington, DC: National Academies Press; 2004.
    1. Berkman ND, Davis TC, McCormack L. Health literacy: what is it? J Health Commun. 2010;15(Suppl 2):9–19. doi: 10.1080/10810730.2010.499985.
    1. Kutner M, Greenburg E, Jin Y, Paulsen C. The health literacy of America's adults: results from the 2003 National Assessment of adult literacy (NCES 2006–483). U.S. Department of Education. Washington, DC: National Center for Education Statistics; 2006.
    1. Berkman ND, Sheridan SL, Donahue KE, Halpern DJ, Crotty K. Low health literacy and health outcomes: an updated systematic review. Ann Intern Med. 2011;155(2):97–107. doi: 10.7326/0003-4819-155-2-201107190-00005.
    1. Sayah FA, Qiu W, Johnson JA. Health literacy and health-related quality of life in adults with type 2 diabetes: a longitudinal study. Qual Life Res. 2016;25(6):1487–1494. doi: 10.1007/s11136-015-1184-3.
    1. Vernon JA, Trujillo A, Rosenbaum SJ, DeBuono B. Low health literacy: implications for national health policy. Department of Health Policy, School of Public Health and Health Services: The George Washington University; 2007. . Accessed 1 Apr 2017
    1. Nutbeam D. Health literacy as a public health goal: a challenge for contemporary health education and communication strategies into the 21st century. Health Promot Int. 2000;15(3):259–267. doi: 10.1093/heapro/15.3.259.
    1. Duell P, Wright D, Renzaho AMN, Bhattacharya D. Optimal health literacy measurement for the clinical setting: a systematic review. Patient Educ Couns. 2015;98(11):1295–1307. doi: 10.1016/j.pec.2015.04.003.
    1. Baker DW, Williams MV, Parker RM, Gazmararian JA, Nurss J. Development of a brief test to measure functional health literacy. Patient Educ Couns. 1999;38(1):33–42. doi: 10.1016/S0738-3991(98)00116-5.
    1. Sayah FA, Williams B, Johnson JA. Measuring health literacy in individuals with diabetes: a systematic review and evaluation of available measures. Health Educ Behav. 2012;40(1):42–55. doi: 10.1177/1090198111436341.
    1. Haun JN, Valerio MA, McCormack LA, Sørensen K, Paasche-Orlow MK. Health literacy measurement: an inventory and descriptive summary of 51 instruments. J Health Commun. 2014;19(Suppl 2):302–333. doi: 10.1080/10810730.2014.936571.
    1. Rothman RL, Montori VM, Cherrington A, Pignone MP. Perspective: the role of numeracy in health care. J Health Commun. 2008;13(6):583–595. doi: 10.1080/10810730802281791.
    1. Frosch DL, Kaplan RM. Shared decision making in clinical medicine: past research and future directions. Am J Prev Med. 1999;17(4):285–294. doi: 10.1016/S0749-3797(99)00097-5.
    1. Rudd RE. Health literacy skills of US adults. Am J of Health Behav. 2007;31(Suppl 1):S8–S18. doi: 10.5993/AJHB.31.s1.3.
    1. Zarcadoolas C, Pleasant A, Greer DS. Understanding health literacy: an expanded model. Health Promot Int. 2005;20(2):195–203. doi: 10.1093/heapro/dah609.
    1. Fagerlin A, Zikmund-Fisher BJ, Ubel PA, Jankovic A, Derry HA, Smith DM. Measuring numeracy without a math test: development of the subjective numeracy scale. Med Decis Mak. 2007;27(5):672–680. doi: 10.1177/0272989X07304449.
    1. Lipkus IM, Samsa G, Rimer BK. General performance on a numeracy scale among highly educated samples. Med Decis Mak. 2001;21(1):37–44. doi: 10.1177/0272989X0102100105.
    1. Nutbeam D. The evolving concept of health literacy. Soc Sci Med. 2008;67(12):2072–2078. doi: 10.1016/j.socscimed.2008.09.050.
    1. Schwartz LM, Woloshin S, Black WC, Welch HG. The role of numeracy in understanding the benefit of screening mammography. Ann Intern Med. 1997;127(11):966–972. doi: 10.7326/0003-4819-127-11-199712010-00003.
    1. Zikmund-Fisher BJ, Smith DM, Ubel PA, Fagerlin A. Validation of the subjective numeracy scale: effects of low numeracy on comprehension of risk communications and utility elicitations. Med Decis Mak. 2007;27(5):663–671. doi: 10.1177/0272989X07303824.
    1. Sørensen K, Van den Broucke S, Fullam J, et al. Health literacy and public health: a systematic review and integration of definitions and models. BMC Public Health. 2012;12(80) 10.1186/1471-2458-12-80.
    1. Baker DW. The meaning and the measure of health literacy. J Intern Med. 2006;21:878–883.
    1. Stewart DW, Vidrine JI, Shete S, et al. Health literacy, smoking, and health indicators in African American adults. J Health Commun. 2015;20(Suppl 2):24–33.
    1. Apter AJ, Cheng J, Small D, et al. Asthma numeracy skill and health literacy. J Asthma. 2006;43(9):705–710. doi: 10.1080/02770900600925585.
    1. Haun J, Luther S, Dodd V, Donaldson P. Measurement variation across health literacy assessments: implications for assessment selection in research and practice. J Health Commun. 2012;17(Suppl 3):141–159. doi: 10.1080/10810730.2012.712615.
    1. McNaughton C, Wallston KA, Rothman RL, Marcovitz DE, Storrow AB. Short, subjective measures of numeracy and general health literacy in an adult emergency department. Acad Emerg Med. 2011;18(11):1148–1155. doi: 10.1111/j.1553-2712.2011.01210.x.
    1. Macek MD, Haynes D, Wells W, Bauer-Leffler S, Cotten PA, Parker RM. Measuring conceptual health knowledge in the context of oral health literacy: preliminary results. J Public Health Dent. 2010;70(3):197–204. doi: 10.1111/j.1752-7325.2010.00165.x.
    1. Weld KK, Padden D, Ricciardi R, Garmon Bibb SC. Health literacy rates in a sample of active duty military personnel. Mil Med. 2009;174(11):1137–1143. doi: 10.7205/MILMED-D-02-4308.
    1. Chew LD, Griffin JM, Partin MR, et al. Validation of screening questions for limited health literacy in a large VA outpatient population. J Gen Intern Med. 2008;23(5):561–566. doi: 10.1007/s11606-008-0520-5.
    1. Wolf MS, Feinglass J, Thompson J, Baker DW. In search of ‘low health literacy’: threshold vs. gradient effect of literacy on health status and mortality. Soc Sci Med. 2010;70(9):1335–1341. doi: 10.1016/j.socscimed.2009.12.013.
    1. Parker RM, Baker DW, Williams MV, Nurss JR. The test of functional health literacy in adults. J Gen Intern Med. 1995;10:537–541. doi: 10.1007/BF02640361.
    1. Anderson BL, Obrecht NA, Chapman GB, Driscoll DA, Schulkin J. Physicians' communication of down syndrome screening test results: the influence of physician numeracy. Genet Med. 2011;13(8):744–749. doi: 10.1097/GIM.0b013e31821a370f.
    1. Galesic M, Garcia-Retamero R. Statistical numeracy for health: a cross-cultural comparison with probabilistic national samples. Arch Intern Med. 2010;170(5):462–468. doi: 10.1001/archinternmed.2009.481.
    1. Hanoch Y, Miron-Shatz T, Himmelstein M. Genetic testing and risk interpretation: how do women understand lifetime risk results? Judgm Decis Mak. 2010;5(2):116.
    1. Hawley ST, Zikmund-Fisher B, Ubel P, Jancovic A, Lucas T, Fagerlin A. The impact of the format of graphical presentation on health-related knowledge and treatment choices. Patient Edu Couns. 2008;73(3):448–455. doi: 10.1016/j.pec.2008.07.023.
    1. Galesic M, Garcia-Retamero R. Graph literacy a cross-cultural comparison. Med Decis Mak. 2011;31(3):444–457. doi: 10.1177/0272989X10373805.
    1. Lipkus I, Hollands J. The visual communication of risk. J Natl Cancer Inst Monogr. 1999;25:149–163. doi: 10.1093/oxfordjournals.jncimonographs.a024191.
    1. Lipkus IM. Numeric, verbal, and visual formats of conveying health risk: suggested best practices and future recommendations. Med Decis Mak. 2007;27(5):696–713. doi: 10.1177/0272989X07307271.
    1. Ancker JS, Senathirajah Y, Kukafka R, Starren JB. Design features of graphs in health risk communication: a systematic review. J Am Med Inform Assoc. 2006;13(6):608–618. doi: 10.1197/jamia.M2115.
    1. Friel SN, Curcio FR, Bright GW. Making sense of graphs: critical factors influencing comprehension and instructional implications. J Res Math Educ. 2001;32(2):124–158. doi: 10.2307/749671.
    1. Gaissmaier W, Wegwarth O, Skopec D, Muller AS, Broschinski S, Politi MC. Numbers can be worth a thousand pictures: individual differences in understanding graphical and numerical representations of health-related information. Health Psychol. 2012;31(3):286–296. doi: 10.1037/a0024850.
    1. Okan Y, Garcia-Retamero R, Cokely ET, Maldonado A. Individual differences in graph literacy: overcoming denominator neglect in risk comprehension. J Behav Decis Mak. 2012;25(4):390–401. doi: 10.1002/bdm.751.
    1. Garcia-Retamero R, Galesic M. Who profits from visual aids: overcoming challenges in people's understanding of risks. Soc Sci Med. 2010;70(7):1019–1025. doi: 10.1016/j.socscimed.2009.11.031.
    1. Peters E, Västfjäll D, Slovic P, Mertz CK, Mazzocco K, Dickert S. Numeracy and decision making. Psychol Sci. 2006;17(5):407–413. doi: 10.1111/j.1467-9280.2006.01720.x.
    1. Betts JR, Grogger J. The impact of grading standards on student achievement, educational attainment, and entry-level earnings. Econ Educ Rev. 2003;22(4):343–352. doi: 10.1016/S0272-7757(02)00059-6.
    1. Stumpf H, Stanley JC. Group data on high school grade point averages and scores on academic aptitude tests as predictors of institutional graduation rates. Educ Psychol Meas. 2002;62(6):1042–1052. doi: 10.1177/0013164402238091.
    1. Cohen J. Statistical power analysis for the behavioral sciences. L. Erlbaum Associates: Hillsdale; 1988.
    1. Jordan JE, Osborne RH, Buchbinder R. Critical appraisal of health literacy indices revealed variable underlying constructs, narrow content and psychometric weaknesses. J Clin Epidemiol. 2011;64(4):366–379. doi: 10.1016/j.jclinepi.2010.04.005.
    1. Koh HK, Brach C, Harris LM, Parchman ML. A proposed ‘health literate care model’ would constitute a systems approach to improving patients’ engagement in care. Health Aff. 2013;32(2):357–367. doi: 10.1377/hlthaff.2012.1205.
    1. DeWalt DA, Broucksou KA, Hawk V, et al. Developing and testing the health literacy universal precautions toolkit. Nurs Outlook. 2011;59(2):85–94. doi: 10.1016/j.outlook.2010.12.002.
    1. Koh HK, Berwick DM, Clancy CM, et al. New federal policy initiatives to boost health literacy can help the nation move beyond the cycle of costly ‘crisis care’. Health Aff. 2012;31(2): 434–443; doi :10.1377/hlthaff. 2011.1169.
    1. McCormack L, Thomas V, Lewis MA, Rudd R. Improving low health literacy and patient engagement: a social ecological approach. Patient Educ Couns. 2017;100(1):8–13. doi: 10.1016/j.pec.2016.07.007.
    1. Griffin JM, Partin MR, Noorbaloochi S, et al. Variation in estimates of limited health literacy by assessment instruments and non-response bias. J Gen Intern Med. 2010;25(7):675-681. doi: .

Source: PubMed

스폰서 및 공동 작업자

건강 상태

약물 개입

3
구독하다