Effects of health literacy on type 2 diabetic patients’ glycemic control, self-management, and quality of life
================================================================================================================

* Bushra A. ALSharit
* Eman A. Alhalal

## Abstract

**Objectives:** To examine the pathway in which health literacy affects diabetic patients’ quality of life (QoL) with self-care management skills and glycemic control levels (hemoglobin A1c [HbA1c]) mediating the relationship.

**Methods:** A cross-sectional study carried out between April 2019 and September 2019. A convenience sample of participants with type 2 diabetes mellitus were recruited from 3 primary healthcare centers, Al Ahsa, Saudi Arabia. Data were collected using structured interviews and HbA1c levels were collected from medical files. Structural equation modeling was also used.

**Results:** Among the 256 participants, 27.3% had a marginal level of health literacy and 35.5% had an inadequate level of health literacy. Health literacy positively affects self-care management, glycemic control (HbA1c), and QoL directly and indirectly. Self-care management partially mediates this relationship.

**Conclusion:** Healthcare providers need to assess health literacy and develop interventions that enhance diabetic patients’ health literacy because it influences self-care management skills, glycemic control, and patients’ QoL. Health literacy should be considered as a key for health education and healthcare encounter to improve health outcomes.

*   diabetes
*   health literacy
*   self-care management
*   quality of life
*   glycemic control
*   structural equation modeling

**H**ealth literacy is a critical concept in healthcare settings and is defined as an individual’s ability to access, comprehend, interpret, and apply information relating to their health.1,2 Increased demands on individuals to take on more responsibility for their health have contributed to the necessity of having adequate education regarding their health.3 Recently, health literacy has been considered as a means by which to attain health and wellbeing, a factor that can reduce health inequality within target populations, and a powerful determinant of the quality of human life in various areas.4-6 Diabetes mellitus (DM) is one of the major chronic diseases that affects approximately 463 million people aged 20-79 years worldwide.7 Type 2 DM is the most common type, as it accounts for 95% of DM cases worldwide (International Diabetes Federation, 2017). If type 2 DM is left unaddressed to the point of becoming unmanageable for the patient, it will lead to serious health complications, such as blindness, nephropathy, neuropathy, and cardiovascular disease.8 There is a 4.5% increase in health expenses relating to diabetes among adults in this category.7 Health information provided by healthcare providers regarding diabetes and time constraints related to making appointments can overwhelm the patient. Therefore, evidence highlights the importance of health literacy as a positive influence on patients with diabetes and their overall health, including any comorbid conditions from which they may be suffering.9,10 Globally, 34.3% of patients with diabetes have limited education regarding health in general.11 In clinical and research settings, health literacy among patients with type 2 DM has received special attention.12 Yet, the pathway in which health literacy can lead to different health outcomes among patients with diabetes requires further studying.

Diabetes encompasses a wide range of self-care activities (such as, self-glucose monitoring, insulin injection, foot care, diet calorie calculation, and adherence to medical therapy) to prevent complications and comorbid conditions from developing.13 Based on the Paasche-Orlow and Wolf theoretical model, health literacy enables patients to acquire self-care management skills.14 Despite the growing evidence supporting how the direct link between health literacy and self-care management skills has a positive outcome for patients, a previous study contradicted these findings, stating that the relationship between self-care management skills and health literacy was inconclusive.15-17 In addition, systematic reviews have revealed that limited evidence existed to support the relationship between health literacy and diabetic patients’ self-care activities, medication adherence, and glycemic control.10,18,19 The hemoglobin A1c (HbA1c) level is an indicator of glycemic control, and maintaining target levels for a long period is associated with a decrease in the incidence of cardiovascular death, nephropathy, neuropathy, and retinopathy.13 Compared with adequate health literacy, inadequate health literacy is independently linked to worse glycemic control with odds ratio ranges of 2.03-4.76.20,21 However, a previous study reported no significant or moderate relationship between health literacy and HbA1c level control.22 Thus, the relationship between health literacy with HbA1c is still inconclusive and requires further studies.23 Moreover, quality of life (QoL) in relation to health plays a crucial role in the health outcomes of patients with diabetes and is thought to be the psychological indicator for controlling the disease; because people make their own judgments regarding their health and wellbeing.24-26 Increased evidence has linked DM with a lower QoL, and health literacy explained 47.5% of the variance that existed in the QoL related to one’s health in patients with diabetes.27,28 However, inconsistent findings have been produced across the board that link poor health literacy and lower health-related QoL among patients with diabetes.29

Various cultural context and health care systems could shape the effect of health literacy on diabetic patients’ health outcomes in different ways.30 The interaction between patients and healthcare systems influences both the patient’s health literacy and health outcomes by providing context for their health in particular.31 Saudi Arabia is among the top 10 countries with the highest rate of diabetes with an incidence of 31.4 per 100,000 individuals.7 Only a few studies have examined health literacy among patients with diabetes, but they have not studied the impact of health literacy on the QoL related to health, self-care management skills, and glycemic control.32,33 Understanding the effect of health literacy on patients with diabetes could provide information and direction for the development of effective interventions. Given the aforementioned gap and need, the present study aims to examine the impact of health literacy on the health outcomes of patients with type 2 DM in Saudi Arabia. The study hypothesizes that among patients with type 2 DM, health literacy affects the QoL related to health, and both self-care management skills and glycemic control (HbA1c) mediate the relationship.

## Methods

Using a cross-sectional design, 3 primary healthcare centers, Al Ahsa, Saudi Arabia, were accessed. These primary healthcare centers are operated under the Saudi Ministry of Health to deliver free preventive and curative services at primary, secondary, and tertiary levels. All these centers are considered the first point of contact for patients within the healthcare system. A convenience sampling method was used to recruit participants during their follow-up appointments between April 2019 and September 2019. The inclusion criteria were male/female adults (aged 18-65 years), diagnosed with type 2 diabetes, and not pregnant. Patients aged 65 years or older were excluded; because of their health conditions and the fact that their needs were different from those of younger patients. The minimum sample size for structural equation modeling (SEM) is 200.34 Thus, 300 participants were approached initially in primary healthcare centers. Of the 300 participants, 269 individuals agreed to participate in the study, resulting in a response rate of 89.7%. The final number of participants included in the analysis was 256; because 13 participants had missing data that were too substantial.

Prior data collection and ethical approvals from the Ministry of Health and King Saud University, Riyadh, Saudi Arabia, were obtained. Potential participants were screened for eligibility, provided with an explanation of the study, and asked to meet the trained data collectors. Informed consents were obtained once participants were selected and face-to-face structured interviews were carried out in private rooms at each center. Subsequently, participants’ medical files were accessed to obtain their HbA1c level data.

Participants were asked about their demographic data, including age, gender, marital status, highest level of education, employment status, income level, and living accommodations.

This study utilized the Brief Health Literacy Screening Tool (BRIEF) health literacy screening tool that measures individuals’ functional health literacy.35 The BRIEF is composed of 4 questions and uses a 5-point Likert scale. The first 3 questions identify patients with marginal and inadequate health literacy, and the fourth question bridges the lack of spoken health information measurements in the literature. The BRIEF scores range from 4-20. The total score can be used to categorize health literacy into 3 scoring groups, where scores from 4-12 indicate an inadequate level of health literacy, scores from 13-16 indicate marginal levels of health literacy, and scores from 17-20 indicate adequate levels of health literacy.35 This tool is proven to accurately identify marginal/inadequate health literacy levels for study participants. Given its brevity, the scale has been used in different country.36,37 Since the scale was not used in an Arab context before, an integrated method of adapting and translating the measurements was used.38 Based on this process, 3 steps were carried out. First, an assessment of the conceptual equivalence of the scale was carried out by 5 bilingual and bicultural healthcare providers who were familiar with the concept of health literacy. They rated each item using a 10-point scale with respect to both the relevance and clarity (comprehension) for Arab context. Based on their rating, the content validity index ranged from 0.87-0.98. Thus, item modifications were not needed because all items were considered culturally relevant and understandable. Subsequently, the forward translation from English to Arabic was carried out by 2 translators. The final Arabic version was put through a pilot test with 30 Saudi patients with diabetes and showed that the Cronbach’s alpha (a) was 0.77. In this study with 256 participants, the Cronbach’s alpha was 0.76.

This study used the Summary of Diabetes Self-Care Activities (SDSCA) scale to measure a variety of self-care management skills.39 Measures include 11 items in 5 subscales of self-care-diet (4 items), physical exercise (2 items), blood monitoring (2 items), foot care (2 items), and smoking (one item).39 It asks questions that can be answered using an 8-point Likert scale (0-7) that reflects the number of days in the previous week when the given activity of self-care was carried out. The mean score for each dimension represents the rate of adherence. The scale was previously used in a different cultural context.40,41 The Arabic SDSCA was adapted and used to include 8 items in 4 subscales: diet (2 items), physical exercise (2 items), self-monitoring of blood glucose (2 items), and foot care (2 items).42 In the present study, the total scale’s Cronbach’s a for internal consistency was 0.83.

The study used the World Health Organization Quality of Life (WHOQOL)-BRIEF scale to measure individuals’ general perception of their QoL.43 The BRIEF measure of WHOQOL is composed of 24 items divided into 4 main domains; environmental (8 items), social relations (3 items), psychological health (6 items), and physical health (7 items), along with 2 items as general questions.44 The scale score is calculated based on the domains, so each score was separately reported by computing the mean of a given domain. Higher domain scores indicated higher QoL in that particular area.45 The BRIEF measure of WHOQOL has significant potential for easy cross-cultural use, as it has been developed and tested in diverse cultures with a Cronbach’s a of >0.7.46-48 For the purpose of the study, the Arabic version was used (44), and the Cronbach’s a for the domains was 0.82 for physical health, 0.82 for psychological, 0.80 for environment, and 0.68 for social. In the analysis, QoL was considered as a latent variable with the 4 domains as indicators.

The most recent HbA1c level was obtained from the patients’ medical files. Hemoglobin A1c level was presented as a percentage, with the normal range being 4-6.4%.13

### Statistical analysis

The Statistical Package for the Social Sciences, version 25.0 (IBM Corp., Armonk, NY, USA) and Mplus version 8 were used to analyze the data. A descriptive analysis was carried out to analyze participants’ demographic data and the study’s variables. Spearman’s correlation analysis was carried out to examine the relationship between health literacy and participants’ demographic characteristics (age, education, and income), whereas the independent samples T-test was used to test the differences in health literacy between male and female participants. To assess the effect of health literacy on each possible health outcome (hypothesis), SEM was carried out using the fit indices that assess the model fit with the data. For an adequate fit, the index values were as followed: comparative fit index (CFI), Tucker-Lewis index (TLI) of ≥0.90, root-mean-square error of approximation (RMSEA), and standardized root-mean-square residual (SRMR) of <0.08.

## Results

Table 1 presents the participants’ background characteristics. Most participants were females (75.4%). With respect to age, 71.9% were aged 41-65 years. Participants had different levels of education, with 15.2% having a bachelor’s degree and 28.5% being uneducated/illiterate. With respect to job status, 5.5% were retired, and 59.0% were unemployed. The percentage of family income levels for 28.5% of the participants was below 5000 Saudi Riyals (SR), whereas 4.7% of the participants’ income level was above 20,000 SR. With respect to healthcare use during the past 12 months, 36.8% of the participants made at least one visit to the emergency department, and 60.5% were admitted at least once due to diabetes.

View this table:
[Table 1](http://smj.org.sa/content/43/5/465/T1)

Table 1 
- Demographic characteristics of the participants (N=256).

Among the 256 participants, 37.1% had adequate health literacy, 27.3% had marginal health literacy, and 35.5% had inadequate health literacy (Table 1). Looking specifically at each item, 38.3% always or often required assistance when reading hospital materials, 19.6% always or often had problems understanding written materials related to their medical condition, 8.6% always or often had problems understanding what was explained to them regarding their medical condition, and 43.4% had little to no confidence in filling out medical forms. A descriptive analysis of the study variables is presented in Table 2. For total functional health literacy, the mean score was 14.08±4.31. The mean score for diabetes self-care management skills was 33.06±7.39. The mean scores for QoL in the 4 domains were as followed: physical domain of 25.31±4.13, psychological domain of 21.84±3.31, social domain of 12.77±1.78, and environmental domain of 27.61±5.01. The mean score of HbA1c level was 8.22±1.15.

View this table:
[Table 2](http://smj.org.sa/content/43/5/465/T2)

Table 2 
- Descriptive statistics of study variables.

Significant correlations were observed between participants’ health literacy and their demographic characteristics in Table 3. The highest positive correlation coefficient was for education (rs (254)=0.671, *p*=0.001), followed by family income (rs (254)=0.346, *p*=0.001), with a negative correlation coefficient for age (rs (254)= -0.375, *p*=0.001). Based on the independent samples t-test results, there was a significant difference between the mean health literacy scores of men and women (t (128.9)= -2.445, *p*=0.016), showing that women had lower health literacy (13.75±4.47) than men (15.11±3.62).

View this table:
[Table 3](http://smj.org.sa/content/43/5/465/T3)

Table 3 
- Spearman’s correlation between health literacy and age, education, and income.

For hypothesis testing, SEM was carried out and showed an adequate fit with the data: χ2 (10) =40.40, CFI=0.965, TLI=0.972, RMSEA=0.010 (90% CI= [0.07-0.14]), and SRMR=0.036. Figure 1 shows the standardized β regression coefficients for each path. With QoL as the latent measure, the loading factors were significant (0.480-0.899). Health literacy positively affects self-management skills (β=0.360; B=0.616; *p*=0.00) and negatively affects HbA1c level (β= -0.297; B= -0.079; *p*=0.00). Moreover, self-management skills positively affect QoL (β=0.670; B=0.313; *p*=0.00), whereas HbA1c levels do not significantly affect it (β=0.050; B=0.150; *p*=0.314). Health literacy directly (β=0.271; B=0.217; *p*=0.00) and indirectly (β=0.241; B=0.193; *p*=0.00) affects QoL through self-care management skills. In other words, only self-care management skills mediate the relationship between health literacy and QoL, whereas a significant correlation exists between self-management skills and HbA1c level (-0.340).

![Figure 1](http://smj.org.sa/https://smj.org.sa/content/smj/43/5/465/F1.medium.gif)

[Figure 1](http://smj.org.sa/content/43/5/465/F1)

Figure 1 
-Structure equation modeling with the standardized regression coefficients.*Significant

## Discussion

The findings from this study are important because type 2 diabetes is the ninth leading cause of death, and 6.3% of the world’s population is composed of patients with diabetes. Our study contributes unique information by showing how health literacy affects health outcomes. The study showed that the mean score of health literacy was 14.08 out of 20. This finding was similar to a previous study in Australia that used the same health literacy screening tool and found that the mean score of the participants’ health literacy was 14.67.49 In addition, our study showed that 62.8% of patients with type 2 DM have suboptimal levels of health literacy (35.5% had inadequate health literacy, and 27.3% had marginal health literacy). This finding was partially consistent with previous studies carried out in different parts of the world where 32.9-64% of patients with diabetes had limited or marginal levels of health literacy. Low health literacy requires attention because inadequate and marginal health literacy levels put a significant financial burden on the healthcare system compared with adequate health literacy.52 Healthcare providers are required to explore effective methods of providing patients with health education.

Identifying patients’ demographic characteristics, which are linked to health literacy, is important for healthcare providers.53 The present study demonstrated that health literacy was positively associated with education and income but negatively associated with age. Discovering that higher education and income levels resulted in higher health literacy scores was congruent with previous findings.11,32 Higher income levels increase the accessibility of education and eventually enhance the skills required to read written materials regarding health management, interpret information, communicate with healthcare providers, and navigate the healthcare system.54 Additionally, when people get older, their health literacy level decreases.55 Healthcare providers should consider educating older patients in person rather than only providing written materials, speak a common language (no jargon), and break information down into smaller parts.56 Although the literature for gender-related differences in health literacy is still inconclusive.57 In our study, women had a lower level of health literacy. Yet, the majority of participants in this study were female, so the comparison may not be precised.

Although the relationship between health literacy and glycemic control is considered inconclusive, the present study found that health literacy affects HbA1c levels.19 Our study also showed that health literacy positively affects self-care management skills for diabetes, which is negatively associated with HbA1c levels. Limited health literacy leads to poorer diabetes self-care management skills, which may affect the control of HbA1c levels. This finding was similar to a structural equation modeling study that found self-efficacy was directly affected by health literacy, which predicted glycemic control.16 To ensure sufficient diabetes self-care management skills, it is necessary for patients with diabetes to possess a high level of health literacy. These skills are needed in day-to-day decision making, such as when measuring blood sugar levels and patients with diabetes need to respond with the appropriate action for the reading they receive.58,59 Healthcare providers can improve the self-care management skills of patients with diabetes by enhancing their health literacy level through educational means, both face-to-face and through written information. This finding addresses the importance of not only treating the individual’s disease but also assessing and strengthening his/her health literacy level.

The present study revealed the direct and indirect effects of health literacy on patients’ QoL, which was measured based on 4 domains: physical, psychological, social, and environmental. The current analysis showed that self-care management skills mediated the relationship between health literacy and QoL. Patients with diabetes possessing an inadequate level of health literacy find it difficult to understand their health status, affecting their ability to manage their health needs and compromising their overall QoL.60 To some extent, this finding was consistent with previous studies with patients with no diabetes.60-62 Quality of life is a major aim for public health as healthcare planners are increasingly realizing that disease metrics alone are insufficient determinants of health status and subjective measures are needed to indicate wellbeing.63 Interventions aimed at enhancing health literacy would positively improve self-care managements skills and patients’ QoL. It is crucial for healthcare providers to consider the differences in the 4 QoL domains to effectively coordinate and create a care plan for their patients.

### Study limitations

The cross-sectional design which does not enable the determination of causality of a predictive relationship. Moreover, relying on self-reported data can be subjected to biases, such as recall bias, respondent bias, or social acceptability bias. Furthermore, using convenient sampling might limit the generalization of the findings. The study only investigated one dimension of health literacy (namely, functional health literacy), which might limit our understanding of health literacy outcomes.

In conclusion, our study demonstrates the importance of health literacy in predicting glycemic control levels (HbA1c levels), diabetes self-care management skills, and QoL among patients with type 2 DM. Self-care management skills mediate the relationship between health literacy and QoL. Patients with diabetes who are given a non-compliance label due to limited health literacy may require special attention. Further research is required to investigate the mediating and moderating effects of different concepts, which were not included in this current study.

## Acknowledgment

*The authors gratefully acknowledge the fund from the Deanship of Scientific Research through the initiative of DSR Graduate Students Research Support (GSR), King Saud University, Riyadh, Kingdom of Saudi Arabia. We also would like to thank Enago ([www.enago.com](https://www.enago.com)) for English language editing.*

## Footnotes

*   **Disclosure.** This study was funded by the Deanship of Scientific Research through the initiative of DSR Graduate Students Research Support (GSR), King Saud University, Riyadh, Kingdom of Saudi Arabia.

*   Received December 29, 2021.
*   Accepted March 21, 2022.


*   Copyright: © Saudi Medical Journal

This is an Open Access journal and articles published are distributed under the terms of the Creative Commons Attribution-NonCommercial License (CC BY-NC). Readers may copy, distribute, and display the work for non-commercial purposes with the proper citation of the original work.

## References

1.  1.Nutbeam D. The evolving concept of health literacy. Soc Sci Med 2008; 67: 2072–2078.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1016/j.socscimed.2008.09.050&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=18952344&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000261993900016&link_type=ISI) 

2.  2.Nutbeam D. Health promotion glossary. Health Promot 1986; 1: 113–127.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1093/heapro/1.1.113&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=10318625&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

3.  3.Coughlin SS, Stewart JL, Young L, Heboyan V, De Leo G. Health literacy and patient web portals. Int J Med Inform 2018; 113: 43–48.
    
    

4.  4.Santana S, Brach C, Harris L, Ochiai E, Blakey C, Bevington F, et al. Updating health literacy for healthy people 2030: defining its importance for a new decade in public health. J Public Health Manag Pract 2021; 27: S258–S264.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1097/PHH.0000000000001324&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=33729194&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

5.  5.Azzopardi-Muscat N, Sørensen K. Towards an equitable digital public health era: promoting equity through a health literacy perspective. Eur J Public Health 2019; 29: 13–17.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1093/eurpub/ckz166&link_type=DOI) 

6.  6.Pleasant A, O’Leary C, Carmona R. Health literacy: global advances with a focus upon the Shanghai declaration on promoting health in the 2030 agenda for sustainable development. Stud Health Technol Inform 2020; 269: 481–496.
    
    

7.  7.International Diabetes Federation. IDF diabetes atlas 2021: 10th edition. [Updated 2021; 2021 Nov 2]. Available from: [https://diabetesatlas.org/idfawp/resource-files/2021/07/IDF\_Atlas\_10th\_Edition\_2021.pdf](https://diabetesatlas.org/idfawp/resource-files/2021/07/IDF\_Atlas_10th_Edition_2021.pdf)
    
    

8.  8.World Health Organization. Global report on diabetes. [Updated 2016; 2021 Sep 20]. Available from: [https://www.who.int/publications/i/item/9789241565257](https://www.who.int/publications/i/item/9789241565257)
    
    

9.  9.Lee HY, Rhee TG, Kim NK, Ahluwalia JS. Health literacy as a social determinant of health in Asian American immigrants: findings from a population-based survey in California. J Gen Intern Med 2015; 30: 1118–1124.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=25715993&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

10. 10.Al Sayah F, Majumdar SR, Williams B, Robertson S, Johnson JA. Health literacy and health outcomes in diabetes: a systematic review. J Gen Intern Med 2013; 28: 444–452.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1007/s11606-012-2241-z&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=23065575&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

11. 11.Abdullah A, Liew SM, Salim H, Ng CJ, Chinna K. Prevalence of limited health literacy among patients with type 2 diabetes mellitus: a systematic review. PLoS One 2019; 14: e0216402.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

12. 12.Estrella ML, Allen-Meares P. Tools to measure health literacy among US African Americans and Hispanics/Latinos with type 2 diabetes: a scoping review of the literature. Patient Educ Couns 2020; 103: 2155–2165.
    
    

13. 13.American Diabetes Association. 15. Diabetes advocacy: standards of medical care in diabetes-2018. Diabetes Care 2018; 41: S152–S153.
    
    [Abstract/FREE Full Text](http://smj.org.sa/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NzoiZGlhY2FyZSI7czo1OiJyZXNpZCI7czoyMDoiNDEvU3VwcGxlbWVudF8xL1MxNTIiO3M6NDoiYXRvbSI7czoxODoiL3Ntai80My81LzQ2NS5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

14. 14.Paasche-Orlow MK, Wolf MS. The causal pathways linking health literacy to health outcomes. Am J Health Behav 2007; 31: S19–S26.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.5993/AJHB.31.s1.4&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=17931132&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000249118000004&link_type=ISI) 

15. 15.Mbaezue N, Mayberry R, Gazmararian J, Quarshie A, Ivonye C, Heisler M. The impact of health literacy on self-monitoring of blood glucose in patients with diabetes receiving care in an inner-city hospital. J Natl Med Assoc 2010; 102: 5–9.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1016/S0027-9684(15)30469-7&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=20158130&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

16. 16.Lee EH, Lee YW, Moon SH. A structural equation model linking health literacy to self-efficacy, self-care activities, and health-related quality of life in patients with type 2 diabetes. Asian Nurs Res (Korean Soc Nurs Sci) 2016; 10: 82–87.
    
    

17. 17.Poureslami I, Nimmon L, Rootman I, Fitzgerald MJ. Health literacy and chronic disease management: drawing from expert knowledge to set an agenda. Health Promot Int 2017; 32: 743–754.
    
    

18. 18.Zhang NJ, Terry A, McHorney CA. Impact of health literacy on medication adherence: a systematic review and meta-analysis. Ann Pharmacother 2014; 48: 741–751.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1177/1060028014526562&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=24619949&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

19. 19.Dahal PK, Hosseinzadeh H. Association of health literacy and diabetes self-management: a systematic review. Aust J Prim Health 2019; 25: 526–533.
    
    

20. 20.Schillinger D, Grumbach K, Piette J, Wang F, Osmond D, Daher C, et al. Association of health literacy with diabetes outcomes. JAMA 2002; 288: 475–482.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1001/jama.288.4.475&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=12132978&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000176955400030&link_type=ISI) 

21. 21.Souza JG, Apolinario D, Magaldi RM, Busse AL, Campora F, Jacob-Filho W. Functional health literacy and glycaemic control in older adults with type 2 diabetes: a cross-sectional study. BMJ Open 2014; 4: e004180.
    
    [Abstract/FREE Full Text](http://smj.org.sa/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NzoiYm1qb3BlbiI7czo1OiJyZXNpZCI7czoxMToiNC8yL2UwMDQxODAiO3M6NDoiYXRvbSI7czoxODoiL3Ntai80My81LzQ2NS5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

22. 22.Cavanaugh K, Huizinga MM, Wallston KA, Gebretsadik T, Shintani A, Davis D, et al. Association of numeracy and diabetes control. Ann Intern Med 2008; 148: 737–746.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.7326/0003-4819-148-10-200805200-00006&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=18490687&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000256372200003&link_type=ISI) 

23. 23.Bailey SC, Brega AG, Crutchfield TM, Elasy T, Herr H, Kaphingst K, et al. Update on health literacy and diabetes. Diabetes Educ 2014; 40: 581–604.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1177/0145721714540220&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=24947871&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

24. 24.Bujang MA, Mohan K, Mohd Hatta NKB, Baharum N, Ismail M. Quality of life and its associated factors among type 2 diabetes patients in malaysian primary health care. Int Med J 2021; 28: 197–201.
    
    

25. 25.Hsu HC, Lee YJ, Wang RH. Influencing pathways to quality of life and HbA1c in patients with diabetes: a longitudinal study that inform evidence-based practice. Worldviews Evid Based Nurs 2018; 15: 104–112.
    
    

26. 26.Wang HM, Beyer M, Gensichen J, Gerlach FM. Health-related quality of life among general practice patients with differing chronic diseases in Germany: cross sectional survey. BMC Public Health 2008; 8: 246.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1186/1471-2458-8-246&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=18638419&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

27. 27.Kiadaliri AA, Najafi B, Mirmalek-Sani M. Quality of life in people with diabetes: a systematic review of studies in Iran. J Diabetes Metab Disord 2013; 12: 54.
    
    

28. 28.Gaffari-Fam S, Lotfi Y, Daemi A, Babazadeh T, Sarbazi E, Dargahi-Abbasabad G, et al. Impact of health literacy and self-care behaviors on health-related quality of life in Iranians with type 2 diabetes: a cross-sectional study. Health Qual Life Outcomes 2020; 18: 357.
    
    

29. 29.Al Sayah F, Majumdar SR, Johnson JA. Association of inadequate health literacy with health outcomes in patients with type 2 diabetes and depression: secondary analysis of a controlled trial. Can J Diabetes 2015; 39: 259–265.
    
    

30. 30.Heijmans M, Waverijn G, Rademakers J, van der Vaart R, Rijken M. Functional, communicative and critical health literacy of chronic disease patients and their importance for self-management. Patient Educ Couns 2015; 98: 41–48.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1016/j.pec.2014.10.006&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=25455794&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

31. 31.Smith SK, Nutbeam D, McCaffery KJ. Insights into the concept and measurement of health literacy from a study of shared decision-making in a low literacy population. J Health Psychol 2013; 18: 1011–1022.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1177/1359105312468192&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=23676466&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000322242500003&link_type=ISI) 

32. 32.Almigbal TH, Almutairi KM, Vinluan JM, Batais MA, Alodhayani A, Alonazi WB, et al. Association of health literacy and self-management practices and psychological factor among patients with type 2 diabetes mellitus in Saudi Arabia. Saudi Med J 2019; 40: 1158–1166.
    
    [Abstract/FREE Full Text](http://smj.org.sa/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Mzoic21qIjtzOjU6InJlc2lkIjtzOjEwOiI0MC8xMS8xMTU4IjtzOjQ6ImF0b20iO3M6MTg6Ii9zbWovNDMvNS80NjUuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

33. 33.Mashi AH, Aleid D, Almutairi S, Khattab F, AlMuqawed AN, Khan S, et al. The association of health literacy with glycemic control in Saudi patients with type 2 diabetes. Saudi Med J 2019; 40: 675–680.
    
    [Abstract/FREE Full Text](http://smj.org.sa/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Mzoic21qIjtzOjU6InJlc2lkIjtzOjg6IjQwLzcvNjc1IjtzOjQ6ImF0b20iO3M6MTg6Ii9zbWovNDMvNS80NjUuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

34. 34.Kline RB. Principles and practice of structural equation modeling: Fourth edidtion. Guilford Press. [Updated 2015; 2021 Nov 10]. Available from: [https://www.guilford.com/books/Principles-and-Practice-of-Structural-Equation-Modeling/Rex-Kline/9781462523344](https://www.guilford.com/books/Principles-and-Practice-of-Structural-Equation-Modeling/Rex-Kline/9781462523344)
    
    

35. 35.Haun J, Noland-Dodd V, Varnes J, Graham-Pole J, Rienzo B, Donaldson P. Testing the BRIEF health literacy screening tool. Fed Pract 2009; 26: 24–31.
    
    

36. 36.Rague JT, Kim S, Hirsch JA, Meyer T, Rosoklija I, Larson JE, et al. Assessment of health literacy and self-reported readiness for transition to adult care among adolescents and young adults with spina bifida. JAMA Netw Open 2021; 4: e2127034.
    
    

37. 37.Theiss LM, Wood T, McLeod MC, Shao C, Santos Marques ID, Bajpai S, et al. The association of health literacy and postoperative complications after colorectal surgery: a cohort study. Am J Surg 2021: S0002–9610(21)00617-6.
    
    

38. 38.Sidani S, Guruge S, Miranda J, Ford-Gilboe M, Varcoe C. Cultural adaptation and translation of measures: an integrated method. Res Nurs Health 2010; 33: 133–143.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=20069612&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

39. 39.Toobert D, Glasgow R. Assessing diabetes self-management: the summary of diabetes self-care activities questionnaire. Harwood Academic Publishers/Gordon. [Updated 1994; 2021 Sep 01]. Available from: [https://psycnet.apa.org/record/1994-98448-000](https://psycnet.apa.org/record/1994-98448-000)
    
    

40. 40.Jannoo Z, Wah YB, Lazim AM, Hassali MA. Examining diabetes distress, medication adherence, diabetes self-care activities, diabetes-specific quality of life and health-related quality of life among type 2 diabetes mellitus patients. J Clin Transl Endocrinol 2017; 9: 48–54.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=29067270&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

41. 41.Ansari RM, Harris MF, Hosseinzadeh H, Zwar N. The Summary of an Urdu version of diabetes self-care activities measure: psychometric evaluation and validation. J Prim Care Community Health 2020; 11: 2150132720935292.
    
    

42. 42.AlJohani KA, Kendall GE, Snider PD. Psychometric evaluation of the summary of diabetes self-care activities-Arabic (SDSCA-Arabic): translation and analysis process. J Transcult Nurs 2016; 27: 65–72.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1177/1043659614526255&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=24841470&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

43. 43.The World Health Organization quality of life assessment (WHOQOL): development and general psychometric properties. Soc Sci Med 1998; 46: 1569–1585.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1016/S0277-9536(98)00009-4&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=9672396&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000074338100005&link_type=ISI) 

44. 44.Ohaeri JU, Awadalla AW. The reliability and validity of the short version of the WHO quality of life instrument in an Arab general population. Ann Saudi Med 2009; 29: 98–104.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.4103/0256-4947.51790&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=19318760&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000266946300002&link_type=ISI) 

45. 45. Whoqol Group. Development of WHOQOL: rationale and current status. Int J Ment Health 1996; 23: 24–56.
    
    

46. 46.Zhang Y, Qu B, Lun S, Wang D, Guo Y, Liu J. Quality of life of medical students in China: a study using the WHOQOL-BREF. PLoS One 2012; 7: e49714.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1371/journal.pone.0049714&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=23209595&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

47. 47.Duarte SBR, Chaveiro N, de Freitas AR, Barbosa MA, Camey S, Fleck MP, et al. Validation of the WHOQOL-BREF instrument in Brazilian sign language (Libras). Qual Life Res 2021; 30: 303–313.
    
    

48. 48.Cheung YB, Yeo KK, Chong KJ, Khoo EY, Wee HL. Reliability and validity of the English-, Chinese- and Malay-language versions of the World Health Organization quality of life (WHOQOL-BREF) questionnaire in Singapore. Ann Acad Med Singap 2017; 46: 461–469.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

49. 49.Ho TG, Hosseinzadeh H, Rahman B, Sheikh M. Health literacy and health-promoting behaviours among Australian-Singaporean communities living in Sydney metropolitan area. Proc Singapore Healthc 2018; 27: 125–131.
    
    

50. 50.Nassar CM, Salameh P. Association between type 2 diabetes mellitus and health literacy, behavioral and environmental risk factors in Lebanon: a case-control study. J Heal Soc Sci 2021; 6: 103–114.
    
    

51. 51.Hussein SH, Almajran A, Albatineh AN. Prevalence of health literacy and its correlates among patients with type II diabetes in Kuwait: a population based study. Diabetes Res Clin Pract 2018; 141: 118–125.
    
    

52. 52.Haun JN, Patel NR, French DD, Campbell RR, Bradham DD, Lapcevic WA. Association between health literacy and medical care costs in an integrated healthcare system: a regional population based study. BMC Health Serv Res 2015; 15: 249.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

53. 53.Palumbo R, Annarumma C, Manna R, Musella M, Adinolfi P. Improving quality by involving patient. The role of health literacy in influencing patients’ behaviors. Int J Healthc Manag 2021; 14: 144–152.
    
    

54. 54.Clouston SAP, Manganello JA, Richards M. A life course approach to health literacy: the role of gender, educational attainment and lifetime cognitive capability. Age Ageing 2017; 46: 493–499.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

55. 55.Gordon Singh S, Aiken J. The effect of health literacy level on health outcomes in patients with diabetes at a type v health centre in Western Jamaica. Int J Nurs Sci 2017; 4: 266–270.
    
    

56. 56.Brach C, Keller D, Hernandez LM, Baur C, Parker R, Schyve P, et al. Ten attributes of health literate health care organizations. [Updated 2012; please provide access date]. Available from: [https://nam.edu/perspectives-2012-ten-attributes-of-health-literate-health-care-organizations/](https://nam.edu/perspectives-2012-ten-attributes-of-health-literate-health-care-organizations/)
    
    

57. 57.Wills J, Sykes S, Hardy S, Kelly M, Moorley C, Ocho O. Gender and health literacy: men’s health beliefs and behaviour in Trinidad. Health Promot Int 2020; 35: 804–811.
    
    

58. 58.Niknami M, Mirbalouchzehi A, Zareban I, Kalkalinia E, Rikhtgarha G, Hosseinzadeh H. Association of health literacy with type 2 diabetes mellitus self-management and clinical outcomes within the primary care setting of Iran. Aust J Prim Health 2018; 24: 162–170.
    
    

59. 59.Omisakin FD, Ncama BP. Self, self-care, and self-management concepts: Implications for self-management education. Int Res J 2011; 2: 1733–1737.
    
    

60. 60.Jovanić M, Zdravković M, Stanisavljević D, Jović Vraneš A. Exploring the importance of health literacy for the quality of life in patients with heart failure. Int J Environ Res Public Health 2018; 15: 1761.
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=http://www.n&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

61. 61.Halverson JL, Martinez-Donate AP, Palta M, Leal T, Lubner S, Walsh MC, et al. Health literacy and health-related quality of life among a population-based sample of cancer patients. J Health Commun 2015; 20: 1320–1329.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1080/10810730.2015.1018638&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=26161549&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 

62. 62.Jayasinghe UW, Harris MF, Parker SM, Litt J, van Driel M, Mazza D, et al. The impact of health literacy and life style risk factors on health-related quality of life of Australian patients. Health Qual Life Outcomes 2016; 14: 68.
    
    

63. 63.Skevington SM, Lotfy M, O’Connell KA. The World Health Organization’s WHOQOL-BREF quality of life assessment: psychometric properties and results of the international field trial. A report from the WHOQOL group. Qual Life Res 2004; 13: 299–310.
    
    [CrossRef](http://smj.org.sa/lookup/external-ref?access_num=10.1023/B:QURE.0000018486.91360.00&link_type=DOI) 
    
    [PubMed](http://smj.org.sa/lookup/external-ref?access_num=15085902&link_type=MED&atom=%2Fsmj%2F43%2F5%2F465.atom) 
    
    [Web of Science](http://smj.org.sa/lookup/external-ref?access_num=000220004500002&link_type=ISI)