Miller, Lisa M. Soederberg : L.M.S. Miller is Associate Professor, Department of Human and Community Development, UC Davis.

RESEARCH ARtICLE â?¼ Cognitive and motivational factors support health literacy and acquisition of new health information in later life Sucsy by Lisa M . Soederberg Miller iStockphoto / David Health literacy refers to the ability to read , understand and use health information to maintain or improve oneâ??s health . Health literacy skills have been linked to outcomes such as medication adherence , improved health and decreased health - care costs . Health literacy is particularly low among older adults . Given demographic projections that 20 % of the U.S . population will be over age 65 by 2030 , there is a pressing need to understand health literacy in later life . We present such a framework , as well as data from two studies that show how cognitive and motivational factors support one aspect of health Health literacy is literacy , namely , the acquisition of needed to understand new health information . A clearer medical information and instructions , communicate understanding of these issues effectively with health professionals and manage will provide insight for targeting oneâ??s own medical educational interventions designed treatment . to increase health literacy among and understand information regarding English - speaking patients , researchers aging adults . illness and treatment options outside of found that more than 30 % could not the medical establishment . Individuals comprehend basic health materials , 25 % ealth literacy refers to the ability with low health - literacy levels may be could not accurately read appointment Hto obtain , process and understand less likely to receive adequate health slips and 40 % could not understand the basic information and services care because they avoid or delay seek - their prescription labels ( Williams et needed to make appropriate decisions ing care . In cases where they do seek al . 1995 ) . The White House Office of regarding oneâ??s health ( Institute of help , they are less able to benefit due to Management and Budget estimated Medicine 2004 ) . The American Medi - comprehension problems during and that language barriers affect some 66 cal Association defines health literacy after the care visit . Furthermore , they million patients annually ( Newman similarly , as â?? the constellation of are less able to regulate the treatment 2003 ) . Moreover , older adults are more skills , including the ability to perform of their chronic basic reading and numeracy tasks , re - diseases , less likely Individuals with low literacy levels may be less quired to function in the health - care to adhere to medi - likely to receive adequate health care because environment . â?쳌 cation regimes and they often avoid or delay seeking care . In general , â?? health literacy â?쳌 includes more likely to visit a broad range of skills including the emergency rooms ability to understand language well ( Murray et al . 2004 ; Schillinger et al . likely to have problems related to health enough to accurately complete medical 2002 ) . Not surprisingly , low health liter - literacy than younger adults ( Rudd et forms , comprehend spoken and written acy has been associated with increased al . 2004 ) . One estimate suggests that medical instructions , and communicate health costs ( Marwick 1997 ) . 30 % to 40 % of English - speaking older symptoms and concerns to medical pro - Low health literacy may be more adults are unable to comprehend writ - fessionals , as well as the ability to seek prevalent than many realize . Among ten health - care information ( Benson http : / / californiaagriculture.ucanr.org â?¢ OCTOBER â?? DECEMBER 2010 189 and Forman 2002 ; Gazmararian et al . adulthood . Because of these changes , among performance , knowledge and 1999 ) . In fact , one study found that older adults may be more likely to con - age are complex , and there are several 2,512 community - dwelling older adults serve cognitive ( Park et al . 1999 ) and models that attempt to capture these with limited health literacy were nearly emotional resources ( Carstensen et al . relationships . According to the migra - twice as likely to die in a 5 - year period 1999 ) . tion hypothesis , older adults sometimes Cognitive ability . Cognitive changes than those with adequate health literacy migrate into higher knowledge groups , in later life can be characterized in ( Sudore et al . 2006 ) . This relationship which in turn protects them from the terms of the mechanics ( the brainâ??s was evident even after controlling for declines experienced by older adults hardware ) and pragmatics ( the brainâ??s age , race , socioeconomic status , current without this knowledge ( Salthouse software ) of intellectual functioning health , health - care access and health - 2003 ) . ( Baltes 1987 ; Salthouse 2000 ) . Aging is related behaviors . This approach is promising be - associated with declines in the mechan - Awareness about the importance of cause past work clearly shows that the ics of functioning , including areas such health literacy is growing . Proposed amount of knowledge individuals pos - as executive function and working approaches to deal with the problem sess regarding their health is closely memory capacity . Working memory is include evaluating public need , identi - tied to measures of health literacy used when individuals hold informa - fying obstacles to effective communica - as well as health outcomes ( Dolan tion in short - term memory while simul - tion , increasing access and usability , et al . 2004 ; Gazmararian et al . 2003 ; taneously performing a computation ; and identifying communication and Kalichman et al . 2000 ; Williams et al . for example , trying to understand a educational strategies appropriate to a 1998 ; Wolf et al . 2005 ) . Greater stores of message left by your doctorâ??s office on targeted audience ( Institute of Medicine health knowledge among older adults your answering machine , while at the 2004 ) . To help specify educational strat - may protect against age declines in same time writing down the telephone egies and interventions to improve the health literacy . Language comprehension . Language number that was spoken quickly during health literacy skills of older adults , comprehension is an important com - the first part of the message . Although research is presented on cognitive and ponent of health literacy . For example , working memory declines in later life , motivational factors that support the ac - individuals listen to and read informa - cognition models also acknowledge quisition of health information in later tion provided by health - care providers . that aging is associated with gains in life . Knowledge acquisition is an impor - They read label instructions to under - pragmatic intelligence , such as word tant component of programs designed stand how to take medications properly meanings ( vocabulary ) , general world to increase health literacy . and handouts regarding post - operative knowledge , and domain - specific knowl - Cognition and motivation care . Individuals also listen to health - edge such as nutrition or oneâ??s chronic A wide array of basic cognitive abili - care providers at clinics , reporters on disease ( Salthouse 2000 ; Schaie 1990 ) . ties such as working memory , knowl - the radio , pharmacists and others they Given the declines in one and pres - edge and language comprehension , as encounter on a regular basis in order to ervation of the other , researchers have well as motivational factors , support make decisions regarding their health . asked whether increases in knowledge health literacy and in particular the Language skills are also used to and experience ( pragmatics ) can offset acquisition of new health information . acquire new health information about or compensate for losses in mechan - Knowledge and motivation may be a particular area . This can occur dur - ics ( Charness 2000 ) . In support of this particularly important in later life due ing brief communication exchanges position , Miller et al . ( 2004 ) showed that to developmental changes that occur in with health - care providers as well as older adults with high levels of knowl - during more extensive searches on the edge were just as iStockphoto / ImageegamI Internet or at a library for information able as younger regarding chronic conditions or treat - adults to learn ment options . about the heart in a However , some aspects of language 2 - hour tutorial , and comprehension are compromised in they were equally later life due to age - related declines in able to apply this working memory and related abilities new knowledge to ( Norman et al . 1992 ; van der Linden et understanding new al . 1999 ) . Language that is grammati - passages about the cally complex or packed with concepts heart as younger is particularly difficult for older adults adults . However , to comprehend ( Wingfield and Stine - other research has Morrow 2000 ) . Indeed , some research shown that age de - shows that older adults have more dif - clines still remain ficulty understanding health informa - within the high - the acquisition of new health information is a function of tion than younger adults ( Brown and knowledge group . basic cognitive skills such as working memory and language comprehension , as well as motivational factors . Park 2002 ) . Relationships 190 CALIFORNIA AGRICULTURE â?¢ VOLUME 64 , NUMBER 4 Images Researchers have examined ways to Business facilitate communication between pro - Shutterstock / Monkey viders and patients . Morrow et al . ( 2006 ) suggested that health materials should be presented in a way that reduces com - prehension demands on general cogni - tive abilities as well as health literacy skills . Their work on medication adher - ence suggests that one way to achieve this goal is through patient - centered in - structions , those written and organized in a way that is useful to the patient . In one study , for example , older adults preferred adherence information in the form of a schedule , and this preference was more pronounced among those with low health - literacy levels ( Morrow et al . 2007 ) . Motivational factors . Oneâ??s ability to comprehend health information is Some aspects of language comprehension may be compromised in late life , making it more critical for health literacy skills ; oneâ??s difficult to understand language that is grammatically complex or densely packed with ideas . willingness to do so is another matter . The extent to which individuals choose are challenging , unpleasant or time necessary to understand what those be - to engage in any particular health lit - consuming . haviors should be . eracy endeavor , including comprehen - Such motivational forces have been Prior knowledge and motivation sion , new knowledge acquisition and widely researched in the area of cog - Health literacy represents a broad decision making , will depend on the nition . For example , control beliefs set of skills , one of which is the ability cognitive resources available ( ability ) and self - efficacy related to memory to comprehend health information so as well as the willingness or motiva - performance have been shown to be that new knowledge is acquired . The tion to expend those resources . This important for cognitive performance , literature suggests that comprehension notion is captured by prominent mod - particularly when the cognitive tasks and learning in later life are dependent els of health behaviors ( Bandura 2005 ; are challenging ( Bandura 1997 ) . Within on cognitive and motivational factors . Leventhal and Mora 2005 ) , which argue the aging literature , researchers have More specifically , prior knowledge that motivational factors are necessary suggested that self - efficacy and control and motivation may support learning for compliance with what individu - beliefs are particularly important for by mitigating declines in processing als may already know to be important older adults because they lead to the mechanics ( e.g . , working memory ) that behaviors . more effective use of strategies , which are likely underlying comprehension Indeed , past research indicates that in turn leads to higher levels of perfor - difficulties . Therefore , prior knowledge interventions focusing only on compre - mance ( Lachman and Andreoletti 2006 ; and motivational factors are likely to hension and knowledge acquisition do Miller and Lachman 1999 ) . Older adults be important for health comprehension not always lead to changes . In nutrition , with a strong sense of control over and learning later in life . knowledge of healthy diets is not suf - their cognitive abilities allocated more We conducted two studies that ex - ficient to encourage individuals to make attention to difficult reading passages amine the roles of knowledge and mo - healthy food choices ( Nebeling et al . than those with a weak sense of control tivation on the acquisition of new health 2007 ) . Motivation is also required . ( Miller and Gagne 2005 ) . These data information . The specific question was Motivational factors underlying suggest that control beliefs may provide whether knowledge and motivation health literacy are not well understood , older adults with the motivation to per - mitigate age - related declines in learn - most likely due to problems surround - sist in the face of a challenging compre - ing about nutrition . In the first study , ing their definition , operation and hension task . motivation specific to nutrition was measurement . Nevertheless , measures Although theoretical work suggests assessed , whereas in the second study , have been developed to tap self - efficacy that self - beliefs are important for health motivation was assessed more broadly and control beliefs ( those surrounding ( Bandura 2005 ) , empirical evidence in terms of health . In both studies , the oneâ??s ability to attain desired goals ) linking these beliefs to health compre - participants were high functioning , related to health outcomes ( Wrosch et hension and health outcomes is lacking . as reflected by years of education and al . 2002 ) and eating behaviors ( Moseley More research is needed to understand scores on working memory measures . 1999 ) . These beliefs may provide mo - factors supporting the likelihood of Study 1 . In study 1 , the sample in - tivation for individuals to persevere adopting healthy behaviors as well cluded 30 younger ( ages 18 to 35 ) , 31 when faced with health behaviors that as engaging the cognitive processes http : / / californiaagriculture.ucanr.org â?¢ OCTOBER â?? DECEMBER 2010 191 middle - aged ( ages 36 to 59 ) and 32 of fruits and vegetables , fat and junk play a larger role in later life by com - older ( ages 62 to 80 ) adults ( data were food . We created a composite measure pensating for age - related declines in the from a larger study ; Miller et al . 2010 ) . of nutrition motivation by averaging mechanics of processing that underlie Participants read two passages ( 1,400 the standardized scores across the three comprehension deficits . Study 2 . The first study included a words total ) at their own pace and measures . Comprehension was assessed motivation assessment specific to nutri - answered multiple - choice comprehen - with a multiple - choice test . tion , but motivation pertaining to more sion questions . The texts described the Consistent with past work on age general health issues was not assessed . health benefits of consuming one of two differences in comprehension and recall In study 2 , the possibility that a more types of foods ( whole grains or fruits ( Johnson 2003 ) , the results showed that general measure of motivation mitigates and vegetables ) and provided informa - comprehension performance signifi - comprehension declines was investi - tion on how to identify these foods cantly declined with age ( r = â?? 0.36 , gated . Data from this study , taken from when selecting groceries . P < 0.001 ) . However , there was a posi - a larger project ( Miller and Gibson Prior to reading the passages , partici - tive association between knowledge 2009 ) , consisted of 102 adults between pants completed a nutrition knowledge and age ( r = 0.24 , P < 0.05 ) . Importantly , the ages of 18 and 81 . Participants read test and a battery of motivational mea - when knowledge was controlled , age a set of nutrition texts and completed sures . The knowledge test contained differences in performance were magni - several comprehension tasks . We focus multiple - choice items ( e.g . , â?? A child fied ( r = â?? 0.46 , P < 0.001 ) , indicating that on responses to a short - answer exercise who is raised on a vegan diet is most without knowledge , older adults â?? per - completed after individuals read the likely to become deficient in ____ â?쳌 ; op - formance would have been even lower . texts ( because it is most similar to the tions : fiber , carbohydrates , vitamin C , A similar pattern was found for motiva - measure used in study 1 ) as well as the etc . ) . The nutrition motivation measure tion . There was a positive age - trajectory health motivation measure , Health - was a composite of three measures : in nutrition motivation ( r = 0.34 , P < Engagement Control Strategies ( HECS ) . the Food Pyramid Self - Efficacy Scale 0.001 ) , and larger age deficits in compre - HECS was designed to assess the ( Moseley 1999 ) , a nutrition interest hension after controlling for motivation degree to which individuals engage scale and a stage - of - change measure . ( r = â?? 0.42 , P < 0.001 ) . in various strategies to control their The Food Pyramid Self - Efficacy Scale These findings are consistent with health outcomes ( Wrosch et al . 2002 ) contained 22 items designed to assess the migration hypothesis ( Salthouse and has been shown to be related to individual perceptions of oneâ??s ability 2003 ) , which suggests that adults mi - health outcomes ( Wrosch and Schultz to follow a healthy diet when placed in grate into higher levels of nutrition 2008 ) . Participants responded to items a wide variety of circumstances , such as knowledge with increasing age , thereby such as , â?? I invest as much time and en - watching television or feeling restless mitigating further age - related declines ergy as possible to improve my health . â?쳌 or bored . The Nutrition Interest Scale in cognitive performance . These find - Knowledge was assessed using an consisted of six items ( e.g . , â?? How inter - ings also extend the notion of migration expanded version of the nutrition test ested are you in knowing the difference to motivation by showing a similar in study 1 ( 38 items ) . As with study between food facts and fallacies ? â?쳌 ) . age - related increase in self - efficacy and 1 , the goal was to determine whether The stage - of - change measure , modeled larger age differences in comprehension knowledge and motivation mitigate after Prochaska and DiClemente ( 1983 ) , when self - efficacy is controlled . The im - age - related declines in comprehension asked individuals to rate their readiness plication of these findings is that knowl - performance . to follow a healthy diet within the areas edge and motivation related to nutrition The results were consistent with the first study , showing an age - related decline in comprehension performance ( r = â?? 0.30 , P < 0.01 ) , as well as a signifi - cant age - related increase in nutrition knowledge ( r = 0.25 , P < 0.01 ) . Also con - sistent with the first study was the find - ing that age - related declines were more pronounced when nutrition knowledge was controlled ( r = â?? 0.46 , P < 0.001 ) . In addition , there was a positive correla - tion between age and health motiva - tion ( r = 0.44 , P < 0.001 ) , indicating that motivation to engage in strategies to control oneâ??s health increases with age . However , the correlation between health motivation and comprehension A study of how age affects learning about nutrition included an was nonsignificant ( r = â?? 0.11 , P > 0.10 ) . assessment of individuals â?? understanding of information in the When motivation was controlled , age USDA Food Pyramid , above , and on nutrition facts panels such as the one for asparagus , right . declines in comprehension performance 192 CALIFORNIA AGRICULTURE â?¢ VOLUME 64 , NUMBER 4 iStockphoto / ImageegamI support information acquisition and health literacy skills ? Recent evidence suggests that nutrition motivation helps individuals sustain attention during a comprehension task ( Miller et al . 2010 ) . It could be that motivation within a do - main provides individuals with the per - severance to engage in health literacy tasks that are cognitively demanding . The samples in the two studies re - ported here were representative of high - functioning adults . Thus , the age effects reported here most likely represent a best - case scenario . It remains unclear how having fewer educational advan - tages would affect the opportunity for older adults to use knowledge and mo - tivation to compensate for age - related declines in the mechanics of processing . Future research on health knowledge Research is needed to identify the motivational factors that promote engagement among seniors acquisition would benefit from a more in education related to healthy behaviors , such as eating nutritious foods . diverse sample , which would help to determine if ( 1 ) motivational factors are were not magnified as in the first study ; constant across various educational or health . This is the case when examining in fact , the correlation was slightly at - socioeconomic groups , and ( 2 ) patterns the relative effects of cognitive control tenuated after controlling for motiva - would be altered if age - related declines beliefs and general control beliefs on tion ( r = â?? 0.27 , P < 0.01 ) . These data fail in comprehension were increased and cognitive performance ; cognitive con - to support the notion that health en - knowledge levels were decreased , as trol beliefs are more highly connected gagement strategies mitigate age - related may be expected within a less - educated to cognitive performance ( Lachman declines in nutrition comprehension . group . Past research suggests that edu - 1986 ) . Similarly , the benefits of nutrition cation would provide a substantial ben - motivation could be due to their overlap Nutrition comprehension and literacy efit for older adults ( Wilson et al . 2009 ) , with nutrition knowledge . In examining Together , data from the two studies but the mechanisms responsible for this the data , there was a significant positive show that nutrition knowledge miti - are not well understood . correlation between nutrition knowl - gated age - related declines in nutrition Increasing health literacy skills edge and motivation in the first study comprehension , and that nutrition among older members of society is a ( r = 0.23 , P < 0.05 ) . In contrast , the as - motivation also mitigated age - related goal that is growing in importance . A sociation between nutrition knowledge declines . However , no mitigation was clearer understanding of factors that and health motivation in the second evident for the health motivation as support health literacy in later life is study was nonsignificant ( r = 0.13 , assessed by HECS . Firm conclusions essential if we are to meet the forthcom - P > 0.10 ) , indicating that individuals regarding which motivators do or do ing demands on our health - care system who reported using frequent strategies not provide additional support to older and ultimately promote older adults â?? to control health outcomes were not adults â?? understanding of nutrition in - quality of life . Research presented here necessarily those with greater stores of formation are not possible without a suggests that prior knowledge plays a nutrition knowledge . wider range of measures within a single critical role in supporting the acquisi - Although speculative , these findings study to make direct comparisons . tion of new health knowledge , which in could indicate that motivating factors Nonetheless , some speculations can turn will support health literacy skills within a health domain have greater be made . One possibility is that older in later life . More effort should be di - effects on older adults when they are adults who use more engagement strat - rected toward educational programs to highly specific to that domain . The egies also have more health problems , promote health behaviors among older knowledge domain addressed here was which in turn offsets any potential ben - adults . nutrition ; however , other specific health efits of increased motivation . Another The data also suggest that motiva - domains ( e.g . , glucose regulation , exer - possibility is that strategies used to tional factors support new knowledge cise ) may show similar advantages . control health behaviors are somewhat acquisition and health literacy skills in Further questions removed from oneâ??s motivation to learn later life . However , associations among Although these findings shed some about and follow a nutritious diet . knowledge , motivation and health lit - light on factors that support health Health motivation that is more specific eracy are complex . Greater effort should literacy in later life , they also raise may be more highly connected to be - be directed toward research that identi - questions . One is , how does motivation haviors than more general measures of fies a wide range of motivational factors http : / / californiaagriculture.ucanr.org â?¢ OCTOBER â?? DECEMBER 2010 193 that encourage engagement in educa - literacy and improving health outcomes to social marketing ( e.g . , encouraging tional activities that promote healthy throughout adulthood . manufacturers to reduce the number of behaviors , such as eating healthy foods foods processed with partially hydro - to prevent or control disease . To be sure , genated oils ( trans fats ) , and identify - knowledge and motivation alone will ing ways to provide affordable fresh L.M.S . Miller is Associate Professor , Depart - not solve the problem of low health lit - fruits and vegetables to consumers in ment of Human and Community Development , eracy or poor dietary habits . However , low - income urban areas ) may provide UC Davis . The National Institutes of Health attention to these factors in addition an initial step toward increasing health ( R01AG19196 ) supported this research . Marwick C . 1997 . Patients â?? lack of literacy may con - Rudd R , Kirsch I , Yamamoto K . 2004 . Literacy and References tribute to billions of dollars in higher hospital costs . Health in America ( Policy Information Report ) . Educa - Baltes PB . 1987 . Theoretical propositions of life - span JAMA 278 : 971 â?? 2 . tional Testing Service , Princeton , NJ . 52 p . developmental psychology : On the dynamics between growth and decline . 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