Heliyon 8 (2022) e09462

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Heliyon
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Research article

General health literacy scale for Thais and comparison between age groups
Ungsinun Intarakamhang a, *, Julaporn Khammungkul b, Piya Boocha c
a
Behavioral Science Research Institute, Srinakharinwirot University, Bangkok, Thailand
b
Srinakharinwirot University, Bangkok, Thailand
c
Innovative Learning Center, Srinakharinwirot University, Bangkok, Thailand

A R T I C L E I N F O A B S T R A C T

Keywords: Background: Health literacy (HL) has captured the world's interest since it was first defined by WHO in 1998. In
Health literacy Thailand, a number of HL scales for risk groups have been developed but none for the general population.
General health literacy scale Therefore, this research aimed to develop a general health literacy (GHL) scale for Thais and compare HL levels
Measurement
between groups, i.e. students, youth, adults, and older.
Methods: In this mixed-methods study, a focus group was conducted with 20 health policy-makers. Data were
collected from 4,000 participants from all regions of Thailand through questionnaires between 2018 and 2019.
The participants were divided into 4 age groups: aged 7–14, 15–24, 25–59, and 60–75. All of them were selected
using stratified random sampling. Data analysis was performed using CFA and ANOVA.
Results: 1) The GHL Scale for Thais comprised 47 items, covering 5 domains i.e. access to health information and
services, understanding of health information and service leading to practice, health information and service
appraisal, communication and social support, and health self-management. The scale had high Cronbach's alpha
values for all participants and different age groups (Cronbach's alpha ¼ 0.95–0.97) and factor loadings ranging
from 0.45 to 0.77. 2) Most Thai people (58.9%) had a fair level of HL, followed by high HL (24.3%) and low HL
(16.8%). 3) The comparison of HL among age groups had different mean scores (P < .05) and low HL was found in
adults (25.00%), older (18.60%), youth (12.60%), and students (11.40%), respectively.
Conclusion: The GHL Scale for Thais can be used to screen people of all ages for potential health problems and
develop strategies for promoting health resilience and preventing disease in each age group.

1. Introduction prevalence, morbidity, and mortality) Therefore, HL programs for people

should include skills-based HL measurement by self-report that can be
Health literacy (HL) is the capacity of individuals to access, under- used in all age groups [4].
stand, and use health information and services to improve and maintain Popular overseas HL assessments include the Rapid Estimate of Adult
good health for themselves, their families, and their communities [1]. It Literacy in Medicine (REALM) [5], The eHealth Literacy Scale (eHEALS)
plays a significant role in enhancing individuals' health. The Department [6], Functional Communication and Critical Health Literacy Scales
of Health, Ministry of Public Health, Thailand [2] has defined HL as the (FCCHL) [7], Test of Functional Health Literacy in Adults (TOFHLA) [8],
ability to consider, evaluate, and make appropriate decisions regarding and The HLS-EU-Q47 by Sørensen et al. [9] which is a HL survey in Europe.
behavior change and health services and products. It has also introduced The HLS-EU-Q47 measures 4 dimensions of HL: access, understanding,
a national strategic plan, aiming to drive all communities towards health appraisal, and application of health information in 3 different domains:
literate societies by 2035. HL is an indicator of Thai people's health cure of disease, disease prevention, and health promotion. The survey
status, relating to risk behaviors and mortality rates. According to pre- consists of 47 items. Another popular HL assessment tool is the Health
vious research, people with low HL have increased risks of hospitaliza- Literacy Questionnaire (HLQ), a HL survey for Australians of all ages. The
tion and mortality and higher medical expenses due to their poor ability HLQ assesses HL needs and the outcomes of both individual and group HL
to understand, communicate with health professionals, and access interventions. The disagree/agree Likert scale comprises 44 items [3].
healthcare services [3]. HL is a major contributor to a person's health The development of Thailand's HL scales started with an ABCDE- HL
skills, behaviors, and health outcomes (e.g., disease incidence, scale for Thai adults with NCDs risks [10] which had three levels and was

* Corresponding author.
E-mail address: ungsinun@gmail.com (U. Intarakamhang).

https://doi.org/10.1016/j.heliyon.2022.e09462
Received 20 May 2021; Received in revised form 25 August 2021; Accepted 12 May 2022
2405-8440/© 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-
nc-nd/4.0/).
U. Intarakamhang et al. Heliyon 8 (2022) e09462

based on Nutbeam's [11] and Manganello et al. [12], consisted of func- the content validity was examined by 5 experts in assessment and health
tional HL, which refers to the ability to obtain and interpret health in- research. The researchers selected items with IOC values ranging from
formation. Interactive HL is communicable skills in extracting 0.80 to 1.00, and tried out the scale on 4 groups (120 people in total) with
information and applying new information to changing conditions. similar characteristics to the research sample: 1) public school students,
Critical HL may be utilized to critically examine the information and use 2) students in vocational colleges, public universities, and private uni-
that information to exert greater influence over life events including versities, 3) workers in the public and private sectors, and 4) older adults
media literacy. The full version consists of 36 items while the short one in urban and rural communities. The reliability of the scale was explored
consists of 19 items. The next developed scale is a HL scale developed using a correlation coefficient at a significance level of 0.05 and a
according to the National Health Recommendations for students aged Cronbach's alpha coefficient of 0.70 and above.
7–14 years. The full version consists of 58 items, and the short one The sample size was determined according to the sample size
consists of 30 items [13]. The next one is the HL Scale for Thai Childhood guidelines for factor analysis suggesting a sample of 500 as very good and
Overweight, consisting of 35-item [14]. This was followed by the HL 1,000 as excellent [21]. The participants in this study consisted of 4 age
Scale for Unwanted Pregnancy Prevention of Thai Female Adolescents, groups (1,000 people per group). All were obtained using multistage
consisting of 38 items [15], and a 5-point HL scale for Thai adult patients sampling. In the first stage, the researchers used cluster random sampling
with diabetes, consisting of 30 items [16]. In addition, HL surveys in to divide the population into 4 groups according to four regional health
2014 found that 95.50% of total 2,001 young Thai females aged 15–21 centers in Thailand: the northern center, the northeastern center, the
years participants had low HL regarding teenage pregnancy prevention, central center, and the southern center. In the second stage, the re-
and 60.40% of 2,000 Thai children and adolescents with obesity aged searchers used stratified random sampling to partition the population
7–14 years had low HL regarding obesity prevention. A HL survey in into 4 subgroups according to age. 250 samples were randomly selected
2016 also revealed that most of the 15,156 Thai students aged 7–14 years for each subgroup, totaling 1,000 samples per region. The total sample
across the country had fair levels of HL according to the National Health size was 4,000. However, the sampling methods had the limitation of
Commandments (63.20%), followed by high HL levels (31.80%) and low infinity and heterogeneous population, the researchers used quota sam-
levels (3.80%). Another HL survey was conducted among 15,278 Thai pling together for distribution of participants including the public and
people aged 15–59 years who were at risk of NCDs. The results showed private school/university students, adults working in public and private
that most of the participants had low levels of HL (49.00%), followed by sectors, and people living in the community. Data were collected by
fair levels (45.50%) and high levels (5.50%) [17]. In addition, the results locally trained researchers, received a response questionnaire consisting
of the invariance analysis of HL measurement models showed no dif- of 1,028 students aged 7–14 years, 980 youth aged 15–24 years, 1,001
ference between male and female adults. However, the mean comparison adults aged 25–59 years, and 991 older adults aged 60–75 years, totaling
of HL and positive attitudes towards the health of adults in urban was 4,000 participants.
lower than in rural communities [18]. The evidence from a government Data were analyzed using descriptive statistics (i.e. frequencies, per-
survey indicated that Thai people had low to flair HL. These results centages, and means), correlational analysis, and confirmatory factor
demonstrated that health promotion or intervention for increasing HL is analysis (CFA) using LISREL. The measurement model was found to be
crucial for the health system. Although, the material for evaluating pa- consistent with the empirical data at an acceptable level (Chi-Square ¼
tients' HL was different by age group. However, there were no standard 1470.99, df ¼ 784, P-value <0.05, RMSEA ¼ 0.05, NFI ¼ 0.98, CFI ¼
tools for assessment in the general healthy population before. The re- 0.99, and SRMR ¼ 0.08).
searchers filled such a gap of knowledge by developing a General HL
assessment tool for Thai people. 3. Results
A HL promotion plan was formulated by the Health Service Support,
Ministry of Public Health, aimed at developing HL knowledge and Five domains of the GHL Scale for Thais were developed: 1) access to
assessment tools for the Thai general population and risks groups and health information and services, 2) understanding of health information
improving Thai people's HL levels by 20%. This prospective study and services leading to practice, 3) health information and service
focusses the importance of the development of HL scales for Thai people appraisal, 4) communication and social support, and 5) health self-
of all ages and thus intended to 1) develop domains for HL measurement, management. The scale comprised 47 items with a 5-point Likert scale
2) measure HL in entire and separate groups, and 3) compare HL levels ranging from 1 (lowest) to 5 (highest). HL scores were interpreted and
between students, youth, adults, and older adults. classified in terms of percentage of individuals with limited HL (below 60
%), moderate HL (no less than 60 to below 80 %), and proficient HL (at
2. Methods least 80 %). The overall Cronbach's alpha value of the scale was high:
0.97 for all participants and 0.96, 0.95, 0.96, and 0.97 for students,
In this mixed-methods study, the researchers followed the principles youth, adults, and older adults, respectively. According to the CFA re-
for participant protection and obtained a certificate of approval for sults, the factor loadings for items ranged between 0.45 and 0.77, as
research involving human subjects No. SWUEC-099/2017 from the uni- presented in Table 1.
versity's ethics committee. The major steps of the research process are The results of a HL study among Thai people revealed that: 1)
detailed below. This research aimed to develop HL domains and scale participant demographics; the majority of the participants (55.50%)
items for the general population by analyzing and comparing domains of lived in suburban areas, were female (58.90%), reported their highest
HL scales based on WHO's [19] definition of HL and studies by Nutbeam level of education as grade 1–6 (38.10%), were single (59.80%t), were
[20], Sørensen et al. [9], and Osborn [3], all of which focused on the farmers (34.70%), had a fair level of economic status with some savings
general population with no context of health problems or diseases. The (46.40%), and had no medical conditions (78.20%); 2) Thai people
present research chose to study general healthy people because HL scales overall had fair HL (58.90%), followed by high (24.30%) and low HL
of WHO focus on general healthy populations, not at risk of chronic (16.80%), respectively; and 3) youth had the highest mean score of HL
diseases or any health problems. A focus group was conducted with 20 (176.74), followed by older adults (166.32), students (166.29), and
public health technical officers who are responsible for formulating the adults (159.17), respectively as following in Figure 1. In addition, the
Ministry of Public Health's policies on health promotion and disease average score on HL of Thai people is classified by age group in Table 2.
prevention. The researchers and the officers examined item consistency, The results of the comparison of HL between age groups indicated
classified items to determine domains based on the definition of HL, and that Thai people of different ages had different levels of HL (F ¼ 70.01, p
decided on a Likert self-report scale in which respondents assess their < 0.05), and different age groups had different scores on all of the HL
ability, cognitive, and social skills. To improve the quality of the scale, domains: Domain 1 ¼ F ¼ 43.11, p < 0.05; Domain 2 ¼ F ¼ 47.57, p <

2
U. Intarakamhang et al. Heliyon 8 (2022) e09462

Table 1. Results of quality assessment of the HL scale.

Domains of Thai people's HL Item-total Factor

correlation loading
1. Access to health information and services (Cronbach's Alpha ¼ 0.81)
1.1 I can look for health information by myself to solve my health problems. 0.59 0.60
1.2 I can look for accurate health information through different sources such as experts and media. 0.60 0.57
1.3 I'm always open to new health information because I want to be healthy. 0.58 0.64
1.4 I can look for health information by myself. 0.52 0.52
1.5 I can look for healthcare providers that will treat my health problems. 0.57 0.45
1.6 I can go to the doctor's or visit healthcare providers whenever I want. 0.46 0.47
1.7 I'm confident that the healthcare providers I selected to suit my needs. 0.57 0.50
1.8 I can look for healthcare providers that suit my problems and my family's problems. 0.56 0.56
2. Understanding of health information and services (Cronbach's Alpha ¼ 0.85)
2.1 I can fill in health forms given by healthcare providers correctly. 0.61 0.68
2.2 I can follow the instructions provided in manuals or documents related to self-care. 0.59 0.74
2.3 I can explain health information obtained from media such as printed materials, brochures, posters, medical prescriptions, applications, 0.57 0.67
Facebook, Line, and YouTube.
2.4 I know and understand health information presented by TV, radio, and online media. 0.56 0.60
2.5 I know and understand healthcare providers' explanations. 0.56 0.72
3. Health information and service appraisal (Cronbach's Alpha ¼ 0.85)
3.1 Before choosing a healthcare provider, I will ask myself what I really want and ask my family about what they want. 0.58 0.62
3.2 I often compare the health information received before deciding to believe or follow that information. 0.59 0.62
3.3 When I receive new health information, I will check the reliability of the source before deciding to believe or follow that information. 0.64 0.65
3.4 I compare health information between different sources to verify my understanding before sharing the information with others. 0.66 0.63
3.5 I know where I can obtain accurate health information for verifying the information received before believing and following that information. 0.64 0.68
3.6 I often seek advice from healthcare providers regarding health instructions before following the information received. 0.63 0.64
4. Communication and social support (Cronbach's Alpha ¼ 0.94)
4.1 I have at least 1 healthcare provider that can give me accurate advice. 0.61 0.56
4.2 I have at least 1 healthcare provider that can give me health information. 0.64 0.64
4.3 I have at least 1 healthcare provider that I can turn to for advice when I have health problems. 0.64 0.68
4.4 I have at least 1 healthcare provider that I can trust to give me health advice. 0.64 0.53
4.5 I have at least 1 healthcare provider that always encourages me in my self-care. 0.63 0.47
4.6 I can contact and communicate with those who have health knowledge. 0.61 0.73
4.7 I have enough people who can help me when I get sick. 0.65 0.67
4.8 I have family members or friends who are ready to help me. 0.66 0.66
4.9 I have at least 1 person that supports me in my self-care. 0.65 0.65
4.10 I have strong supporters who always give me moral support. 0.67 0.56
4.11 I'm confident that healthcare providers will understand me when we communicate. 0.66 0.71
4.12 I can ask healthcare providers about what concerns me or what I want to know. 0.63 0.76
4.13 I can discuss and exchange knowledge about self-care guidelines with healthcare providers. 0.66 0.75
4.14 I ask healthcare providers about my health so I can take better care of myself. 0.68 0.77
4.15 I can contact healthcare providers for health information to relieve my doubts. 0.66 0.66
4.16 I often exchange information with healthcare providers. 0.62 0.61
4.17 I can explain health information to others clearly. 0.61 0.64
5. Health self-management (Cronbach's Alpha ¼ 0.90)
5.1 I have good health knowledge and information for managing my health. 0.62 0.61
5.2 I have enough health information for taking care of myself when I'm sick. 0.61 0.75
5.3 I have enough health information for preventing my sickness. 0.65 0.64
5.4 I have enough health information necessary for taking care of my health. 0.65 0.65
5.5 I spend a lot of my time on self-care activities. 0.64 0.62
5.6 I plan to do activities necessary for achieving good health. 0.63 0.62
5.7 Even though I'm busy, I still make time for taking care of my health. 0.63 0.69
5.8 I set exercise and self-care goals and intend to achieve them. 0.62 0.54
5.9 I regularly observe my physical and mental changes to take better care of myself. 0.66 0.56
5.10 I improve the surrounding environment to ensure that I live in an environment that promotes good health. 0.61 0.57
5.11 I participate in health activities with healthcare providers. 0.60 0.55

0.05; Domain 3 ¼ F ¼ 57.41, p < 0.05; Domain 4 ¼ F ¼ 72.04, p < 0.05; 4. Discussion
and Domain 5 ¼ F ¼ 49.65, p < 0.05. The comparison of differences in
mean HL scores between pairs of groups found that all pairs had different The General HL Scale for Thais was developed based on the principles
mean HL scores at a significance level of 0.05, except for students and of the development of the HLQ by Osborn et al. [3] which is a psycho-
older adults, as presented in Table 3. metric test with a Likert scale that assesses attitudes, capabilities, and

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U. Intarakamhang et al. Heliyon 8 (2022) e09462

Figure 1. The HL measurement among Thai people separated groups.

to be considered acceptable, a newly developed instrument should have a

Table 2. The mean scores on HL of Thai people classified by age group and reliability coefficient of 0.70 or higher [22, 23]. The scale also had
overall.
discriminating power ranging from 0.46 to 0.68, consistent with the
Domains of Thai people's HL Mean scores minimum acceptable total-item correlation of 0.30 [24], and an accept-
Students Youth Adults Older Overall able level of construct validity. Judging by the statistically significant
adults factor loadings of over 0.45, this HL scale was highly reliable and could
1. Access to health information 27.72 29.81 27.37 28.35 28.30 be used to measure Thai people's HL across 4 age groups.
and services The HL assessment found that most Thai people had fair HL (58.90%)
2. Understanding of health 17.25 18.98 17.45 17.77 17.85 and low HL (16.80%) on all of the five domains. The results are consistent
information and services with a study on health literacy and health behavior among Thai people
3. Health information and 21.37 22.82 20.42 21.25 21.46 by the Health Service Support Department, Ministry of Public Health
service appraisal
[13]. The study revealed that most children and adolescents aged 7–14
4. Communication and social 61.46 64.18 56.88 60.44 60.73
years and working people aged 15–59 years had medium levels of HL
support
(63.80% and 47.40%, respectively). The assessment results are also in
5. Health self-management 38.50 40.85 37.04 38.51 38.71
agreement with the HL survey among 17,530 Thai people aged over 15
Thai people's HL 166.29 176.64 159.17 166.32 167.05
by the Health Systems Research Institute [25]. According to the survey,
65% of Thai people had medium HL while 19% (approximately 10
million people) had low HL in terms of the ability to use health infor-
Table 3. The comparison of HL differences in mean scores between pairs of mation and knowledge as well as basic health services to take care of
groups. their health. Considering each age group separately, the youth had high
Age Mean, SD Students Youth Adults Older HL on all domains and a higher mean score than other age groups, which
groups adults indicates that young people can access and understand health informa-
(166.29, (176.64, (159.17, (166.32, tion and services well enough to practice, can check health information
0.84) 0.86) 0.85) 0.85) and services, have communication skills and social support, and can
Students (166.29, 0.84) - manage their health well. This may be explained by the fact that youth
Youth (176.64, 0.86) 10.35* - develop more healthcare decision-making processes, can analyze and
Adults (159.17, 0.85) -7.12* -17.47* - understand new things quickly, have interests, and abilities to commu-
Older (166.32, 0.85) 0.03 -10.32* 7.15* - nicate and use mobile technology to seek health information and are
adults likely to be triggered by different stimuli in online sources of health in-
(*p < 0.05). formation [26]. Young people in the 21st century have more knowledge
and understanding of health management and can access health services
online better than other age groups [27] because they use technology to
behavior. It applied WHO's [19] definition of HL that encourages in- communicate and access information in their daily lives more than adults
dividuals to develop cognitive and social skills which will lead to their [28, 29] and most of the health services today are also available on the
motivation and ability to access, understand, and use health information internet [30]. This is consistent with a study by Manganello [31] which
and services to enhance and maintain good health. The scale also suggested that adolescents had media literacy and skills needed to seek
included the two levels of HL: interactive HL and critical HL based on health information and frequently used mass media and technology to
Nutbeam's concept [11]. In terms of benefits, this scale can be used to access health information and services. Media literacy is thus an impor-
classify the characteristics of people in all age groups who do not tant factor contributing to good HL [32, 33, 34]. A previous study showed
necessarily risk groups or patients and classify people before organizing that most Thai university students had high levels of HL, especially in
training activities to ensure that the activities adjust or reinforce certain terms of access to health information and services, health communication
behaviors with regard to a specific domain or item. skills, capability to make decisions that promote health, and media lit-
With reference to instrument quality, the scale was tested for both eracy [35]. The results are consistent with foreign research that found
construct validity and content validity. For the scale's test-retest reli- that young people had HL and rated their own health good or tended to
ability, the scores obtained from both times were similarly high. In order evaluate it in a more positive way. A study by Ghaddar et al. [33]

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U. Intarakamhang et al. Heliyon 8 (2022) e09462

indicated that most students in a secondary school in the United States Funding statement
had high HL (52%) and that young people's HL was positively associated
with their perceived self-efficacy and seeking for health information This work was supported by Health Education Division, Ministry of
online. Some studies, however, found that adolescents had HL and rated Public Health of Thailand.
their health medium [12, 36, 37, 38]. Youth with high HL can assist other
groups of people in obtaining self-care knowledge from different sources Data availability statement
and help explain health information and services to other people.
The developed scale in this study has a limitation due to its situation- Data associated with this study has been deposited at http://bsri
based questions. Respondents' scores may differ according to their s.swu.ac.th/upload/283350.pdf.
different experiences. The scale should be used to assess and compare HL
among people who have similar backgrounds or are in similar situations.
Declaration of interests statement
It is also recommended that the scale be used to assess each age group's
HL before and after organizing a learning or training activity. Different
The authors declare no conflict of interest.
activities should be conducted for different age groups due to their
different interests and learning abilities based on the child learning
theory (pedagogy) in which children learn for their future and careers Additional information
and the adult learning theory (andragogy) in which adults tend to be
interested in learning subjects that are relevant to their experience or No additional information is available for this paper.
problems considered as important life lessons [39].
Research recommendations. 1) Public health personnel are recom- References
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