Easton et al. BMC Public Health 2010, 10:459 http://www.biomedcentral.com/1471-2458/10/459 health literacy were no less likely to say that the doctor answered all their questions, but they were significantly less likely to say their doctors asked their opinion about treatment, or that they explained things so they could understand [35]. Collectively these 6 studies suggest that in relation to health service use, the differences between people with higher and lower levels of literacy are to be found less in terms of initial gaining of access to services and more in terms of the appropriateness of patterns of use and the securing of appropriate treatment. Relationships with healthcare staff featured in an addi- tional study of 157 parents of children aged one to four who had visited a well-child clinic. Those with a REALM score below 9th grade reported higher quality patient-provider relationships compared to those with scores of 9th grade or higher, through better family- centred care, helpfulness and confidence building [34]. Relationship between functional or health literacy and self-management of health problems Eight studies examined associations between functional or health literacy and aspects of self-management of manifest health problems. Four studies used quantitative techniques to assess adherence to medication and reported a relationship between lower functional literacy or health literacy and poorer adherence, [36-39] two of them in relation to parents administering medication to their children [38,39]. A further two studies focused on parental ability to administer medication to their children [25,40]. One study investigated women’s compliance with follow up treatment [24]. One qualitative study of 25 people infected with HIV investigated the perceived clarity and level of difficulty of self-report HIV medication adherence measurement tools. Patients found it difficult to define adherence, had difficulty identifying medication and in recalling missed doses [41]. These difficulties have implications both for patients’ adherence and for research that seeks to inves- tigate this. Studies of people living with HIV/AIDS found that in a sample of 381 people, those with lower health literacy were significantly more likely to miss at least one dose of medication over a 2 day period [36] and in another study of 87 HIV+ patients, that higher health literacy was associated with 95% or greater adherence over 3 months [37]. The two studies used different health lit- eracy measures, Kalichman et al considering low health literacy to be less than 86% correct on the TOFHLA [36] and Graham et al comparing those with a REALM score below 9th grade level with those 9th grade or above [37]. Both studies considered relatively small Page 6 of 10 variations in adherence but findings were consistent over the two widely different timescales. In a retrospective cohort study of 150 parents of chil- dren with asthma, those with low health literacy had used rescue medication for their children more fre- quently and in greater amounts. They also had a signifi- cantly greater incidence of hospitalisation and days missed from school as well as an increase in emergency department visits which approached significance [38]. In a cross-sectional study of 78 children with type 1 dia- betes, glycemic control was correlated with mothers’ functional literacy as measured by NART scores [39]. In one cross-sectional study of 181 parents and care- givers, those with lower health literacy, measured by the TOFHLA, reported greater use of nonstandardised dos- ing instruments to give their children medication and this may impact on their adherence to the medication [40]. Another study of 543 parents found no association between parents’ total scores on the REALM and their ability to administer their child’s medication [25]. Compliance with recommended follow-up interven- tions was the focus of one study of 68 women who had had an abnormal pap smear. This study considered both physicians’ subjective assessments of women’s health lit- eracy and more objective measurement using the REALM. Although there was a high level of agreement between the two, only subjective physician assessment of patient health literacy was a significant predictor of failure to follow up [24]. Knowledge of particular health risk or health conditions as a mediator between functional health literacy and health behaviours Twelve studies focused on or included associations between functional or health literacy levels and knowl- edge about health conditions or treatment [25,27,35,37,38,40-42] or health risks [22,23,30,43]. Most, but not all of the studies, demonstrated lower knowledge of the various topics of interest in those with lower health literacy; two studies found that knowledge did not necessarily mediate behaviour [30] or adherence [37]. One study found that lack of knowledge was asso- ciated with behaviour likely to impact on adherence but adherence itself was not assessed [40]. Knowledge of HIV/AIDS in 372 patients offered HIV testing was poorer in those with lower health literacy [42]. One paper reported that in a sample of 294 people living with HIV/AIDS, those with lower health literacy were significantly more likely to believe that HIV trans- mission was less likely if anti-HIV medication was taken or if viral load was undetectable [35]. Poorer knowledge of their health status; [27,35] poorer knowledge of medi- cation [41] and more mistaken beliefs about their