Health literacy, complication awareness, and diabetic control in patients with type 2 diabetes mellitus

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Health literacy, complication awareness, and diabetic control in patients with type 2 diabetes mellitus

ISSN: 0309-2402

Accession: 00004471-200804010-00009

Full Text (PDF) 103 K

Author(s):	Tang, Ying Ho; Pang, Samantha M.C.; Chan, Moon Fai; Yeung, Grace S.P.; Yeung, Vincent T.F.
Issue:	Volume 62(1), April 2008, p 74–83
Publication Type:	[RESEARCH PAPER: ORIGINAL RESEARCH]
Publisher:	Copyright © 2008 Blackwell Publishing Ltd.
Institution(s):	Ying Ho Tang BSc MSc RN Diabetes Nurse Medical and Geriatric Department, Our Lady of Maryknoll Hospital, Hong Kong SAR, China Samantha M.C. Pang PhD RN Professor and Head School of Nursing, Hong Kong Polytechnic University, Hong Kong SAR, China Moon Fai Chan PhD Cstat Assistant Professor Kiang Wu Nursing College of Macau, Macau, SAR, China Grace S.P. Yeung BN MHA DipHSc RM RN General Manager Department of Family Medicine and Primary Health Care, Our Lady of Maryknoll Hospital, Hong Kong SAR, China Vincent T.F. Yeung MSc MD FRCP Director Centre for Diabetes Education and Management, Consultant and Chief of Service, Department of Medicine and Geriatrics, Our Lady of Maryknoll Hospital, Hong Kong SAR, China Correspondence to H.Y.H. Tang: e-mail: tangyh2@ha.org.hk Accepted for publication 5 October 2007

Keywords: complication awareness, diabetic control, health literacy, nursing, Short-form Test of Functional Health Literacy in Adults (C-S-TOFHLA), type 2 diabetes mellitus

Abstract

Aim: This paper is a report of a study to examine the relationship between health literacy, complication awareness and diabetic control among patients with type 2 diabetes mellitus, and to validate a Chinese version of the Short-form Test of Functional Health Literacy in Adults.

Background: There is a rapidly increasing trend in the prevalence of diabetes mellitus in Asian countries. Alongside the considerable progress in recent decades of health education in the field of diabetes care, the effects of health literacy and complication awareness have received increasing attention over the past 10 years.

Method: This study was conducted from September 2005 to February 2006 with 149 Chinese patients (mean = 59·8 years, range: 27–90 years) who were undergoing/had undergone diabetic complication assessment. Survey data were collected using a structured questionnaire incorporating demographics; assessment of complication awareness in two sections: a self-developed 10-item patient awareness score and a modified Chinese version of the Summary of Diabetes Self-Care Activities measure; and health literacy as measured by the Chinese version of the Short Test of Functional Health Literacy in Adults. Diabetic control was assessed by the most recent HbA1c level.

Findings: Health literacy (P<0·001) class="fulltext-IT">P=0·035), but management of treatment in the Summary of Diabetes Self-Care Activities measure (P=0·030), gender (P=0·023) and duration of diabetes (P<0·001)>

Conclusion: To develop effective patient education and improve patients' diabetic control and own complications, educational strategies need to consider patients' health literacy levels and self-care skills.

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What is already known about this topic

* The effects of health literacy and complication awareness have received increasing attention over the past 10 years.

* Poor health literacy is common among racial and ethnic minorities, older people, and patients with diabetes mellitus.

What this paper adds

* Patients who have only completed primary schooling or a few years of school are highly likely to have inadequate or marginal health literacy.

* Patients with diabetes mellitus who are unlikely to comprehend even the simplest written patient educational materials are likely to need more direct teaching and follow-up by healthcare professionals.

* Validation of a Chinese version of the Short-form Test of Functional Health Literacy in Adults in a sample of patients with diabetes in Hong Kong.

Introduction

Diabetes mellitus (DM) is one of the diseases most commonly encountered by healthcare professionals. The worldwide incidence of type 2 diabetes is projected to increase sharply from the current 171 million in 2000 to 366 million by 2030 (Wild et al. 2004). Cockram (2000) has estimated that the Asia-Pacific region had the largest diabetes population – more than 30 million – and that this will double by 2025. Further, there is a rapidly increasing prevalence (8%) of the disease in Asian countries (Cockram 2000). More recent data from certain Chinese cities indicate that this increase may be even more pronounced, with a prevalence as high as 9·2% in Hong Kong (Lam et al. 2000).

Background

Early studies have revealed that optimal glycaemic control is the ideal primary preventive measure against the development of complications (Diabetes Control and Complications Trial Research Group 1993, UK Prospective Diabetes Study Group 1998). A complementary strategy is to focus on the primary prevention and secondary prevention of diabetic complications in individuals who have already developed DM. It is also well known that treatment for DM complications such as cardiovascular and limb diseases, retinopathy, neuropathy and nephropathy consumes most of the costs of diabetes care (Gilmer et al. 2005). However, most patients still do not know this, especially if they have not received adequate diabetes education.

Building on the considerable progress in recent decades of health education in the field of DM care, the effects of health literacy and complication awareness have received increasing attention over the past 10 years (American Medical Association 1999). Diabetes educators implementing self-management programmes must assess levels of health literacy for their target population. This assessment will enable them to develop strategies for communicating more effectively with patients. Such strategies should be based on a deeper understanding of the needs and competencies of patients with poor health literacy (Williams et al. 1998, Schillinger et al. 2000). Health literacy refers to a person's ability to read, understand and act on medical instructions. A previous study showed that patients with diabetes with inadequate health literacy and hypertension have poorer disease knowledge than those with adequate health literacy (Williams et al. 1998). Poor health literacy is common among racial and ethnic minorities, older people, and patients with chronic conditions, particularly in public sector settings. People with poor health literacy may have lower awareness of their disease condition, which may have an impact on their diabetic control. Studies that measure Chinese patients' health literacy have not been reported so far.

Health literacy

Health literacy is the ability to perform the essential reading and numerical tasks required to function in the healthcare environment (American Medical Association 1999). Several studies have shown that more than one-third of English-speaking patients have low health literacy (Williams et al. 1998, Gazmararian et al. 2003). Patients with the greatest healthcare needs may have the least ability to read and understand the information needed to function successfully as patients (American Medical Association 1999). Inadequate health literacy may interact to influence health outcome (Williams et al. 1998).

Research applications in health literacy need to focus on literacy screening, methods of health education, medical outcomes and economic costs as well as understanding the causal pathway of how health literacy influences health. Health literacy such as an enabling skill for learning from print materials is associated with diabetes outcomes (Schillinger et al. 2000). Kim et al. (2004) found that lower health literacy was associated with older age and having less education, lower income and more self-reported diabetes complications, and that patients with high health literacy reported better adherence to diet, self-glucose monitoring and foot care. Chew et al. (2004) suggest that patients with inadequate health literacy might be at risk of unawareness to preoperative instructions, leading to increased morbidity and delay in medical treatment. The above studies show that inadequate functional health literacy might pose a major barrier to educating patients with chronic disease. Health literacy has been assessed using the Short-form Test of Functional Health Literacy in Adults (S-TOFHLA) (Baker et al. 1999). The S-TOFHLA has been tested with good validity and reliability. This instrument has been widely used for English-speaking people, but no Chinese version has been available to date.

Complication awareness

Afridi and Khan (2003) state that knowledge about the disease is not adequate in the majority of patients with diabetes. They suggested that an adequate knowledge of the disease through health education was associated with good metabolic control and prevention of the complications associated with diabetes and its treatment (Afridi & Khan 2003). Patients' complication awareness is equivalent to a measurement of their knowledge level of their disease and self-management (Glasgow et al. 1989, 2005). Tunney and Shanks (2003) classify awareness in terms of subjective and objective categories. Both sets of criteria are predicated on assumptions about the relationship between a measure of performance on one hand, and a measure of awareness of the information that influences performance on the other. A dissociation between performance and awareness is taken to indicate unconscious cognition. Therefore, healthcare professionals need to develop their understanding of health care and the professional–patient interaction to support patients' learning (American Diabetes Association 2003).

Several studies have led to an understanding of patient self-management (Goodall & Halford 1991, Tunney & Shanks 2003, Tham et al. 2004). Professional interventions aimed at influencing patient behaviour in relation to diabetes by the provider–patient interaction would have to address patient behaviour determinants. The education programme is one of the interventional methods that can enhance patients' awareness of their health condition and self-management (Franz et al. 1994, Jaarsma et al. 1999). An informed approach can lead patients to have a better awareness of the parameters relating to their care, and to take an active part in their own care (Charnock et al. 1999). Accurate diabetes knowledge can help patients make more informed decisions, but they will not act on this information unless they are strongly motivated to do so (Jimenez et al. 2005). Generally, knowledge alone is poorly related to behaviour (Day 2000). Among informed diabetic subjects, various aspects such as cost and lack of motivation need to be addressed to close the gap between knowledge and practice, especially with regard to regular exercise and self-monitoring of blood glucose (Jaarsma et al. 1999, Day 2000).

Studies on the relationship between patients' complication awareness and their diabetic control have been conducted several times in the West but rarely in the East (Jaarsma et al. 1999, Tham et al. 2004, Boulton 2005). Boulton (2005) found that diabetic peripheral neuropathy influences up to 50% of older type 2 patients with diabetes, and whilst acknowledging that people may not be aware of sensory loss, there is a discrepancy between the levels of diabetic people who are aware of neuropathy as a potential complication and the prevalence of this complication. Management involves establishing that the neuropathy is caused by diabetes rather than more threatening causes and aiming for optimal glycaemic control.

Diabetic control

Glycaemic control is essential to the management of DM (Gilmer et al. 2005), and the levels of HbA1c should reflect that glycaemic control is poor or good. The HbA1c test, a patient's average of glycaemia over the preceding 2–3 months can be measured (Sackis et al. 2000). The proportion of patients with acceptable glycaemic control compared with that of patients with poor control has frequently been used as a chance to improve the well-being indicator for DM (Amos et al. 1997, Williams et al. 1998, Lam et al. 2000, Schillinger et al. 2000, Gazmararian et al. 2003, Chew et al. 2004). Undoubtedly, a major limitation to the available information is that we do not recognize the optimum level of control for particular patients, as there are individual differences in the risk of hypoglycaemia and other adverse effects (Lam et al. 2000). Earlier studies showed that improved glycaemic control is associated with a sustained decreased rate of complications such as retinopathy, nephropathy and neuropathy (Ruggiero et al. 1997, American Medical Association 1999). Therefore, it is suggested that patient knowledge of recent and target HbA1c levels is a useful precondition for involvement in diabetes management (Heisler et al. 2005).

The study

Aim

The aim of the study was to examine the relationship between health literacy, complication awareness and diabetic control among patients with type 2 DM, and to validate a Chinese version of the Short-form Test of Functional Health Literacy in Adults (C-S-TOFHLA).

Design

A descriptive and correlational study was conducted, and recruitment was performed in the diabetes education management centre of a public hospital. In the study hospital, patients with diabetes are referred to the centre to undergo annual complication screening by different units, including inpatient, general outpatient and specialist outpatient clinics. However, these patients may or may not have attended diabetes educational classes. Clinical experience showed that some patients appreciated the arrangement of educational classes and complication screenings, but others did not. For example, they complained about time constraints or financial problems, and therefore failed to attend the appointments. Some were reluctant to attend the classes because they were not aware of the importance of complication screening or had not learned enough about the complications of diabetes and were unaware of their own potential or established DM complications.

Participants

Potential patients for inclusion in the study were those with type 2 DM characterized by disorders of insulin action and insulin secretion, either of which could be the predominant feature, and who were at least 18 years old. They also had to be able to read or write Chinese and give informed consent. Patients were excluded if they had severely impaired vision, i.e. worse than 20/100, unintelligible speech, or overt psychiatric illness (Schillinger et al. 2000, Chew et al. 2004). A convenience sampling method was used, and the recruitment period was between September 2005 and February 2006.

Power calculation

The power of this study was estimated based on the correlation between the health literacy score, one of our primary outcomes, and patients' HbA1c level. From two studies (Schillinger et al. 2000, Kim et al. 2004), a low correlation coefficient (=0·21) was found. Although this value was small, we still used it for our power analysis because it was the most relevant information available for us to estimate required samples for this study. Therefore, we employed the regression model; the required sample size was around 149, which could achieve 80% power at a 5% level of significance (nQuery Advisor 2001).

Data collection

Data were collected via face-to-face interviews with a structured schedule, and the most recent HbA1c levels were collected from medical records. The average time for the interviews was about 30 minutes.

Interview schedule

Part 1 – Demographic information

Part 1 of the instrument comprised demographic information, including age, gender, duration of DM (years), education level, insurance, receiving DM education, social activity in the past 3 months, employment status, marital status, type of DM treatment and current HbA1c level.

Part 2 – Patients' complication awareness

Part 2 was designed to measure patients' complication awareness, and comprised two sections. Section 1 was a modified Chinese version of the Summary of Diabetes Self-Care Activities (C-SDSCA) measure, comprising 15 items formulated to measure patients' self-care activities and management of diabetes (ranging from 0 to 7). The original SDSCA measure assessed only five aspects of the diabetes regimen: general diet, specific diet, exercise, medication taking, and blood glucose testing. The SDSCA has been tested and found to have good validity and reliability (Toobert et al. 2000). Although this instrument has been widely used for English-speaking people, no Chinese version was available before this study. Therefore, we translated the SDSCA into a Chinese version, and invited a DM nurse who was fluent in English and Chinese to back-translate it into English. We invited another DM nurse who was also fluent in both languages to compare the meaning of each statement of the original and back-translated versions, and results show that the meanings of all statements in both versions were exactly the same. In addition, one item in the C-SDSCA was slightly modified to account for use in this study to assess patients' awareness of chronic or acute DM complications according to a study by Wee et al. (2002). The C-SDSCA assesses several aspects of patients' self-care: nutrition (2 items), specific diet (2 items), smoking status (1 item), exercise (2 items), self-monitoring of blood glucose (2 items), foot care (3 items), management of treatment (2 items), and one item for management of symptoms of hypoglycaemia.

Section 2 was the patient awareness score, comprising 10 pairs of items to measure patients' awareness of their medical records and complication screening reports.

Part 3 – Chinese Short-Form Test of Functional Health Literacy in Adults

Part 3 was the C-S-TOFHLA, comprising 40 items to measure patients' health literacy levels and with a total score ranging from 0 to 100. The S-TOFHLA was already available in English and Spanish. Briefly, the S-TOFHLA uses actual materials that patients might encounter in the healthcare setting and consists of reading, comprehension and numeric sections. Scores are categorized into three levels of health literacy: inadequate (0–53), marginal (54–66) and adequate (67–100). The numeric section is a 4-item test using actual hospital forms, prescription bags and appointment slips. The four numeric questions were translated into Chinese. The reading comprehension section is a 36-item test using the modified cloze procedure (Baker et al. 1999); that is, every fifth to seventh word in a passage is omitted and four multiple choice options are provided. We identified two actual Chinese sets of patient information: (a) on preparation for a colonoscopic examination series and (b) the patient rights and responsibilities section of a Medicaid application normally completed on admission into hospital.

Because of the differences between the S-TOFHLA and the C-S-TOFHLA, new cutoffs for inadequate and marginal functional health literacy were established by two steps. First, a normality test was used to examine the C-SDSCA, C-S-TOFHLA and patient awareness data (Shapiro & Wilk 1965). Results showed no statistically significant differences, confirming they were normally distributed. Second, the cutoffs were established at 58 and 66, and so the C-S-TOFHLA can be categorized into three levels: inadequate (0–58), marginal (59–66) and adequate (67–100).

Validity and reliability of the instrument

Validity

The validity of the Chinese instrument was then assessed by three experts (one clinical diabetologist and two nurse-specialists) and examined using the content validity index (CVI) (Waltz et al. 1991). According to Waltz et al. (1991), the CVI score of a valid instrument should be >=0·75. The experts were required to evaluate the format and content of the instrument and to give their comments on each question and the overall instrument. They then sent back the completed validation form to the researcher within 2 weeks. After collecting all of the validation forms, the comments of the experts were used to evaluate the extent of agreement with the instrument, yielding a CVI score of 0·80.

Confirmatory factor analyses (CFA) were conducted to establish the construct validity for C-S-TOFHLA, C-SDSCA and the patient awareness score. Unlike traditional factor analysis, CFA enables the researcher to construct and statistically test hypotheses about the relationship between observed variables and the constructs they are assumed to measure (Jöreskog & Sörbom 1993). CFA were conducted using AMOS (Arbuckle 1999). The following factor models were assessed: (1) for C-S-TOFHLA, a two-factor model; (2) for C-SDSCA, an eight-factor model and (3) for the patient awareness score, a one-factor model. A covariance matrix was used as the starting point for the estimation process and the maximum-likelihood function was used to estimate the parameters. The assessment of fit for the present study was based on (a) the [chi]² likelihood ratio; (b) the ratio of the [chi]² to its expected value ([chi]²/d.f.), a ratio of 2 or less being judged as an acceptable fit (Bentler 1990); (c) the goodness-of-fit index (GFI); (d) the adjusted goodness-of-fit index (AGFI); (e) the comparative fit index (CFI), a revised norm fit index corrected for sample-size dependency and (f) the root mean square residual (RMR), an index of the average discrepancy between the observed and hypothesized covariance matrices (Marsh & Hocevar 1985, Bentler 1990). Table 1 presents the goodness-of-fit indices of the factor model assessed for each part of the instrument. For the C-S-TOFHLA, non-significant [chi]² values (P=0·059) indicate that the data set was accounted for by the two-factor model postulated in part 1. The [chi]² ratio was under the critical value (1·07 < class="fulltext-SP">2 ratio below the critical value (1·22 < class="fulltext-SP">2 goodness-of-fit statistic was not statistically significant (P=0·112) and the [chi]² ratio was under the critical value (1·17 <>

Table 1 Goodness-of-fit indices of the factor model for C-S-TOFHLA, C-SDSCA, and patient awareness scores (n=149)

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Reliability

Internal consistency was evaluated for the C-S-TOFHLA, C-SDSCA and patient awareness score with Cronbach's alpha coefficients. The C-S-TOFHLA showed an acceptable internal consistency. For the four numeric items, the Cronbach's alpha was 0·63, and for the 36 cloze items in the reading comprehension section the Cronbach's alpha was 0·96. The C-SDSCA also showed an acceptable internal consistency. For the two nutrition items, two specific diet items, two exercise items, two self-monitoring of blood glucose items and three foot care items, the Cronbach's alpha was 0·98, 0·81, 0·65, 0·88 and 0·62, respectively. The two management of treatment items were mutually exclusive, and thus Cronbach's alpha was not performed. The same applied to the smoking status and management of symptoms of hypoglycaemia items. For the 10-paired patient awareness score, the Cronbach's alpha was 0·69, also showing acceptable internal consistency.

Ethical considerations

The study was approved by the ethics committees of the university and the study hospital. The researcher explained the study to potential participants. Written informed consent was obtained before conducting the study. Confidentiality was assured, and participants were told that they could withdraw from the study at any point without adverse effects on their subsequent care.

Data analysis

Descriptive statistics were used to describe the patients' characteristics. For the univariate analysis, the chi-squared, Fisher's exact, correlation, independent t-, Mann–Whitney U and Kruskal–Wallis tests were used to examine the association or difference between patients' HbA1c level and their characteristics. Spearman's coefficient (r_s) was used to examine whether there was any association between the health literacy and complication awareness factors and patients' HbA1c level. For the multivariate analysis, a stepwise regression analysis was performed to examine which factors contributed to the prediction of patients' HbA1c level when adjusted by other factors, and a significant value was set when P<0·05.

Findings

To determine which factors were associated with HbA1c, both univariate and multivariate analyses were performed. First, a univariate analysis was used. For the characteristics factors (see Table 2), increased duration of DM was significantly associated with reduced levels of HbA1c (r_s=-0·20, P=0·016) but no statistically significant correlations were found with age (r_s=0·08, P=0·317), length of time receiving education from a DM nurse (r_s=-0·14, P=0·083), and level of social activity (r_s=0·13, P=0·111). In addition, it was found that male patients had better levels of HbA1c than female patients (U=2018·5, P=0·005), and those with insurance had lower HbA1c levels than those without (U=1916·5, P=0·025). However, no statistically significant links were found with marital status ([chi]²=3·72, P=0·156), receiving education from a DM nurse (U=2417·0, P=0·508), employment status (U=2493·5, P=0·333), DM treatments ([chi]²=7·35, d.f.=3, P=0·062), and living status (U=440·0, P=0·296). With Relationships among patients' awareness, C-SDSCA, and health literacy factors (see Table 3), patients' higher awareness (r_s=–0·26, P=0·002), management of treatment (r_s=0·18, P=0·029) and C-STOFHLA (r_s=–0·32, P<0·001)>

Table 3 Correlation of sample's complication awareness and health literacy with HbA1c level (n=149)

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Table 2 Comparison and correlation of sample characteristics with HbA1c level, n=149

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However, no statistically significant links were found between HbA1c level and nutrition (r_s=-0·08, P=0·360), specific diet (r_s=0·05, P=0·549), smoking status (r_s=-0·06, P=0·464), exercise (r_s=-0·01, P=0·899), blood glucose self-monitoring (r_s=-0·16, P=0·850), foot care (r_s=0·12, P=0·148) and management of symptoms of hypoglycaemia (r_s=-0·06, P=0·497).

Second, a multivariate analysis (multiple regression analysis) was used to identify a model to predict the HbA1c (see Table 4). In an adjusted model, gender, duration of DM, having insurance, patient awareness score, C-SDSCA (management of treatment) and C-S-TOFHLA were included for analysis. The results showed that being male (beta=0·34, P=0·023), reduced duration of DM (beta=0·005, P<0·001), beta="–0·20," class="fulltext-IT">P=0·035), C-S-TOFHLA (beta=–0·12, P<0·001) beta="0·15," class="fulltext-IT">P<0·030) class="fulltext-IT">F=180·86, P<0·001), class="fulltext-IT">R² of 98·6% (see Table 3).

Table 4 Adjusted multiple regression on HbA1c level, n=149

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Discussion

Study limitations

Our study had several limitations. First, the samples came from one local hospital only, and this selection bias may have affected the results. Second, study participants were from a sample of patients actually attending complication screening, thus defaulting patients were ignored and the sample might not be representative of all patients with diabetes. Finally, as regards the results from the relationship between each factor and HbA1c levels, most of these relationships were less than or around 0·20, except for health literacy score (r_s = -0·32). The relationships were weak, although statistical significance was met; therefore caution is needed in using them as clinical indicators to predict HbA1c levels. Also, as the relationships examined here have received little study, we have used the conventional statistical significance levels to help identify potential relationships worth additional research. However, the importance of the weak relationships is open to interpretation.

Discussion of results

To our knowledge, this study is the first to examine, in Chinese, the relationships among health literacy, complication awareness and HbA1c control level for type 2 DM patients. Our findings indicate that individuals with high complication awareness and good management of treatment can affect their HbA1c levels. These findings are consistent with those seen previously in the literature (Glasgow et al. 1989, Franz et al. 1994). Specifically, patients mostly reported closely following their medication regimen, followed by self-management of treatment, and were least likely to follow recommendations for lifestyle changes, such as diet and exercise. Diabetes education needs to routinely provide clear, preferably written, and consistent goals on all key aspects of diabetes self-management for all individuals. For example, it would be helpful to ask individuals to describe their understanding of the specifics of the recommendations before leaving the clinic, and to conduct follow-up phone calls to the patients to confirm that they are clear about the instructions once they attempt to initiate the recommendations at home (Goodall & Halford 1991). Peyrot et al. (2006) showed that healthcare providers see psychosocial problems as having greater impact on diabetes self-management, and believe that applied psychosocial strategies are important components of diabetes care. Their findings support our suggestions that such care should be provided, and such findings should have a positive impact for nurses as they continue to provide such care for diabetes patients in Hong Kong.

Our results also have implications for patient education applications. Patients who have only completed primary or a few years of schooling are highly likely to have inadequate or marginal health literacy. Conversely, those with education beyond secondary school are highly likely to have adequate health literacy. This suggests that we need to ensure that patient education takes into account health literacy levels. If patients are entering formal DM patient education programmes, including both group and individual provision, it may be helpful to screen for inadequate or marginal health literacy to identify those who are unlikely to comprehend even the simplest written materials. These people are likely to need more direct teaching and follow-up by healthcare professionals.

To help guide such educational programmes, healthcare educators should also consider screening the general patient population at their hospitals to determine the proportion of patients with inadequate or marginal health literacy. This would help healthcare providers to allocate proportionate human resources, numbers of direct and indirect teaching programmes, and time to different patient groups.

Conclusion

In today's healthcare environment, nurses have less time for patient education. To deal with the lack of time to teach patients about self-management, nurses often rely on the written word, leaving patients with poor health literacy at a substantial disadvantage. As our study demonstrates, good complication awareness and high health literacy result in good diabetic control. In contrast, failure to consider these relationships would likely lead to worse diabetic control. To be more successful, future patient education efforts must consider these two factors. In order to improve patients' diabetic control and awareness of complications, educational strategies need to take into consideration their health literacy level and self-care skills. Tailor-made strategies are needed to cater for patients with low health literacy levels so as to enhance treatment adherence and improve diabetic control. Our study also has relevance for a very wide nursing audience, as low levels of literacy and health literacy are encountered in all populations, including ethnic majority groups in developed Western countries.

Acknowledgement

We wish to acknowledge the invaluable collaboration of the staff of the study hospital, and the patients willing to participate in this study. Thanks also to Ms Yiu Chui Han, Ms Kwan Yee Mei and Ms Lau Siu Wai for giving us the benefit of their clinical expertise.

Author contributions

YHT, SMCP, GSPY and VTFY were responsible for the study conception and design and YHT, SMCP, MFC, GSPY and VTFY were responsible for the drafting of the manuscript. YHT performed the data collection and YHT and MFC performed the data analysis. YHT, SMCP and MFC made critical revisions to the paper. MFC provided statistical expertise. SMCP supervised the study.

References

Afridi M.A. & Khan M.N. (2003) Role of health education in the management of diabetes mellitus. Journal of the College of Physicians and Surgeons Pakistan 10, 558–561. [Context Link]

American Diabetes Association (2003) Standards of medical care for patients with diabetes mellitus. Diabetes Care 26, S33–S50. [Context Link]

American Medical Association (1999) Health literacy: report of the Council on Scientific Affairs. Ad Hoc Committee on Health Literacy for the Council on Scientific Affairs. The Journal of the American Medical Association 281, 552–557. [Context Link]

Amos A.F., McCarty D.J. & Zimmet P. (1997) The rising global burden of diabetes and its complications: estimates and projections to the year 2010. Diabetes Medicine 14(Suppl. 5), S1–S85. [Context Link]

Arbuckle J.L. (1999) AMOS 4·01. Retrieved from http://smallwaters.com on 16 February 2007. [Context Link]

Baker D.W., Williams M.W., Parker R.M. & Gazmararian J.A. (1999) Development of a brief test to measure functional health literacy. Patient and Education Counsel 38, 33–42. [Context Link]

Bentler P.M. (1990) Comparative fit indexes in structural models. Psychological Bulletin 12, 151–157. [Context Link]

Boulton A.J.M. (2005) Management of diabetic peripheral neuropathy. Clinical Diabetes 23, 9–15. [Context Link]

Charnock D., Shepperd S., Needham G. & Gann R. (1999) Discern: an instrument for judging the quality of written consumer health information on treatment choices. Journal of Epidemiological Community Health 53, 105–111. [Context Link]

Chew L.D., Bradley K.A. & Boyko E.J. (2004) Brief questions to identify patients with inadequate health literacy. Family Medicine 36, 588–594. Bibliographic Links [Context Link]

Cockram C.S. (2000) Diabetes mellitus: perspective from the Asia-Pacific region. Diabetes Research and Clinical Practice 50(Suppl. 2), S3–S7. [Context Link]

Day J.L. (2000) Diabetic patient education: determinants of success. Diabetes / Metabolism Research and Review 16, 70–74. [Context Link]

Diabetes Control and Complications Trial Research Group (1993) The effect of intensive treatment of diabetes on the development progression of long-term complications in insulin-dependent diabetes mellitus. The New England Journal of Medicine 329, 977–986. Bibliographic Links [Context Link]

Franz M.J., Horton E.S., Bantle J.P., Beebe C.A., Brunzell J.D., Coulston A.M., Henry R.R., Hoogwerf B.J. & Stacpoole P.W. (1994) Nutrition principles for management of diabetes and related complications. Diabetes Care 17, 490–518. Bibliographic Links [Context Link]

Gazmararian J.A., Williams M.V., Peef J. & Baker D.W. (2003) Health literacy and knowledge of chronic disease. Patient Education and Counseling 51, 267–275. [Context Link]

Gilmer T.P., O'Connor P.J., Manning W.G. & Rush W.A. (2005) The cost to health plans of poor glycemic control. Diabetes Care 20, 1847–1853. [Context Link]

Glasgow R.E., Toobert D.J., Riddle M., Donnelly J., Mitchell D.L. & Calder D. (1989) Diabetes-specific social learning variables and self-care behaviors among persons with type II diabetes. Health Psychology 8, 285–303. Bibliographic Links [Context Link]

Glasgow R.E., Ory M.G., Kleges L.M., Cifuentes M., Fernald D.H. & Green L.A. (2005) Practical and relevant self-report measures of patient health behaviors for primary health care research. Annals of Family Medicine 3(1), 73–81. Bibliographic Links [Context Link]

Goodall T.A. & Halford W.K. (1991) Self-management of diabetes mellitus: a critical review. Health Psychology 10, 1–8. Bibliographic Links [Context Link]

Heisler M., Piette J.D., Spencer M., Kieffer E. & Vijan S. (2005) The relationship between knowledge of recent HbA1c values and diabetes care understanding and self care. Diabetes Care 28, 816–822. Bibliographic Links [Context Link]

Jaarsma T., Halfens R., Huijer A.H., Dracup K., Gorgels T. & Van Ree J. (1999) Effects of education and support on self-care and resource utilization in patients with heart failure. European Heart Journal 20, 678–682. [Context Link]

Jimenez L., Mendez C. & Cleeremans A (2005) Measures of awareness and of sequence knowledge. Retrieved from http://psyche.cs.monash.edu.au/v2/psyche-2-33-jimenez.html on 29 March 2005. [Context Link]

Jöreskog K.G. & Sörbom D. (1993) LISREL 8: User's Reference Guide. SPSS Inc., Chicago, USA. [Context Link]

Kim S., Love F., Quistberg D.A. & Shea J.A. (2004) Association of health literacy with self-management behavior in patients with diabetes. Diabetes Care 27, 12–17. [Context Link]

Lam T.H., Liu L.J., Janus E.D., Lam K.S. & Hedley A.J. (2000) Fibrinogen, other cardiovascular risk factors and diabetes mellitus in Hong Kong: a community with high prevalence of non-insulin dependent diabetes and impaired glucose tolerance. Diabetes Medicine 17(11), 798–806. [Context Link]

Marsh H.W. & Hocevar D. (1985) Application of confirmatory analyses to the study of self-concept: first- and higher-order factor models and their invariance across groups. Psychological Bulletin 97, 562–582. [Context Link]

Peyrot M., Rubin R.R. & Siminerio L.M. (2006) Physician and nurse use of psychosocial strategies in diabetes care. Diabetes Care 29, 1256–1262. [Context Link]

nQuery Advisor (2001) Statistical Solutions. Belfast, North Ireland. [Context Link]

Ruggiero L., Glasgow R.E., Dryfoods J.M., Rossi J.S., Prochaska J.O., Orleans C.T., Prokhorov A.V., Rossi S.R., Greene G.W., Reed G.R., Kelly K., Chobanian L. & Johnson S. (1997) Diabetes self-management: self-report recommendations and patterns in a large population. Diabetes Care 20(4), 568–576. Bibliographic Links [Context Link]

Sackis D.B., Brum D.E., Goldstein D.E, Maclaren N.K., McDonald J.M. & Parrott M. (2000) Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus. Diabetes Care 25, 750–786. [Context Link]

Schillinger D, Grumbach K. & Piette J. (2000) Association of health literacy with diabetes outcomes. The Journal of the American Medical Association 288, 475–482. [Context Link]

Shapiro S.S. & Wilk M.B. (1965) An analysis of variance test for normality (complete samples). Biometrika 52, 591–611. [Context Link]

Tham K.Y., Ong J.J.Y., Tan D.K.L. & How K.Y. (2004) How much do diabetes patients know about diabetes mellitus and its complications? Annals of the Academy of Medicine Singapore 33, 503–509. [Context Link]

Toobert D.J., Hampson S.E. & Glasgow R.E. (2000) The summary of diabetes self-care activities measure, results from 7 studies and a revised scale. Diabetes Care 23, 943–950. [Context Link]

Tunney R.J. & Shanks D.R. (2003) Subjective measures of awareness and implicit cognition. Memory & Cognition 31, 1060–1071. Bibliographic Links [Context Link]

UK Prospective Diabetes Study Group (1998) Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes. Lancet 352, 837–853. Bibliographic Links [Context Link]

Waltz C.F., Strickland O.L. & Lenz E.R. (1991) Measurement in Nursing Research, 2nd Edn. F.A. Davis, Philadelphia, PA, USA. [Context Link]

Wee H.L., Ho H.K. & Li S.C. (2002) Public awareness of diabetes mellitus in Singapore. Singapore Medical Journal 43(3), 128–134. Bibliographic Links [Context Link]

Wild S., Roglic G., Green A., Sicree R. & King H. (2004) Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care 27(5), 1047–1053. Bibliographic Links [Context Link]

Williams M.V., Baker D.W., Parker R.M. & Nurss J.R. (1998) Relationship of functional health literacy to patients' knowledge of their chronic disease: a study of patients with hypertension and diabetes. Archives of Internal Medicine 158, 166–172. [Context Link]

Keywords: complication awareness; diabetic control; health literacy; nursing; Short-form Test of Functional Health Literacy in Adults (C-S-TOFHLA); type 2 diabetes mellitus

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