Introduction

Oral diseases can affect the overall quality of one’s life, with consequences including pain, discomfort, dysfunction or aesthetic issues [1]. These diseases have been designated as the ‘silent epidemic’ [2] even when they consistently remain one of the most common ailments of today.

The oral health of a person is affected by both structural and behavioral factors. The structural factors contain socio-economic level [3] and capital [4], and the behavioral factors comprise the diet factor [5], mentality for self-care [6] and proper utilization of necessary dental care [7, 8]. But these factors can be modified by health literacy [9] and it requires citizens to access, process and comprehend basic information regarding oral health, necessary to make optimal health decisions [10]. Lower oral health literacy (OHL) scores were associated with decreased brushing frequency among adults [11]. Ueno et al. also established a relation between lower OHL and consumption of sugar and fizzy drinks [11].

Health literacy is an emerging public health research topic [12], and has been rightly set out as a key component on the European Health Agenda [13].

Researchers and practitioners are confronted with the evidence that the educational materials, forms, directives and informed consent documents used in the field of medicine and dentistry are above the level of layman’s tongue [14]. This can also become a threat to necessary communication, understanding and even for the delivery of effective treatment [15]. The little research that has been conducted mostly emphasized on assessing the ability to read consent forms and dental educational materials [16]. Furthermore, health literacy is a necessity from the legal side, to ensure adequate protection regarding ethical concerns due to patient autonomy while filling out informed consent procedures [17]. Health literacy intertwines with empowerment and enhances the ability of the people to make proper informed decisions in all topics related to health in private or public spaces including political front [17].

Even though the ‘health literacy’ concept originated from the USA, it is now internationally acclaimed, both in the health care sector and in the context of public health [18]. It is included even in the European Commission White Paper entitled ‘Together for Health’ [19]. According to a comparative study by Sørensen et al. [13], 10.3% of total population in Ireland has inadequate general health literacy. This might be slightly better than Bulgaria (26.9%) or Austria (18.2%) but it still has room for necessary improvements [19]. Individuals with inadequate HL might have issues following prescription instructions, providing complete medical history or insurance, test result interpretations, comparing the risk and benefits of a procedure and even efficient communication with the health care provider [20].

Although substantial importance is given to general health literacy, OHL as such is not promoted. This is clearly comprehensible from the lack of studies conducted in the EU region [21].

Communication with oral health providers is the modifier to better oral health, along with OHL and navigation of the health system. OHL deficits can restrict effective patient-dentist communication [22].

A study solely focused on OHL has not been undertaken in Ireland, to the best of my knowledge. Oral health status of a person is inexorably intertwined with overall health and wellbeing, as demonstrated by the relation between chronic diseases such as diabetes, respiratory disease or cardiovascular diseases and below average oral health [21].

It is crucially important that health literacy levels of the general population are adequate for better impacts of public health policies [23]. It is also important that the educators introduce health literacy in their school or college curriculum.Therefore, we set out to conduct this study with the following objectives:

  1. 1.

    To estimate prevalence of OHL among third-level university students in Cork City.

  2. 2.

    To identify potential correlates of OHL, including self-rated oral health status.

Materials and methods

EEthical approval

Ethical approval was obtained from the School’s Social Research Ethics Committee before the commencement of the study.

A descriptive observational cross-sectional study on oral health literacy, amongst the third-level students in UCC (University College Cork), was conducted. An online survey using the Lime Survey tool was employed for data collection. The survey was sent by the university webmaster to approximately 21,000 students [24] in UCC between April 20 and June 21,2018. The participation was entirely voluntary. A previously validated oral health literacy tool with modifications was administered which included questions on:

  1. i.

    Socio-demographics

The characteristics collected included age group, gender, major discipline. Additional two questions on financial security were added and specific scores were assigned to each recorded answer. A final score for financial security for each participant was derived, which was the weighted average of the two questions.Availability of a regular dentist was also queried with a polar question.

  1. ii.

    Oral health literacy assessment questions

OHL was the main independent variable of interest and OHL score was derived from three previously validated screening questions [25] and scores were assigned as 0 (all the time), 1 (occasionally or a moderate amount of time), 2 (some or little of the time) and 3 (rarely or none of the time); 0 being ‘worst’ and 3 being ‘best’ r.

The average of these responses were further grouped into specific ranges 0.0–1.0 (inadequate health literacy), 1.1–2.0 (marginal health literacy) and 2.1–3.0 (adequate health literacy) to estimate prevalence of OHL within these three distinct categories. For estimating the overall prevalence of limited OHL, we combined marginal health literacy and inadequate health literacy.

  1. iii.

    Self-reported oral health condition

It has been reported that self-rated oral health is a reliable and valid pointer of overall OH status [26, 27]. A single question to assess the perceived oral health with values 1 to 5 (1—poor, 2—fair, 3—good, 4—very good, 5—excellent) was provided. To dichotomize the variable, participants with scores 1 or 2 were grouped together as poor or fair and those with 3, 4 or 5 were categorized as good, very good or excellent, respectively. A similar question was provided to attain the self-rated oral health attitude [21].

  1. iv.

    Patient–dentist communication

Three questions were asked to obtain information on the patient–dentist communication, as it has significant impact on therapeutic outcomes, as previously shown [28]. Each question had 3 options and each answer was awarded a score of 0, 1 or 2. From this, the respective communication ranges were calculated as 0.0–2.0, 2.1–4.0 and 4.1–6.0 in which 4.1–6.0 was taken as better patient–dentist communication and 0.0–2.0 as poor communication.

Statistical analysis

The data generated was saved in Microsoft Excel spreadsheet before being analysed using the statistical analysis software IBM SPSS 24. Descriptive statistics was calculated. The variance in the OHL, attitude and behaviour between students from different schools, age and gender was assessed using a chi-squared test.

To establish the correlation (Pearson) between the variables OHL and other potential correlates, only the completed responses (n = 663) were analysed, and the Pearson correlation coefficient (‘r’) was estimated across any 2 variables. Amongst them, the categorical variables were coded with dummy variables and the total score was obtained for financial status, patient–dentist communication and OHL. The data synthesized was scrutinized by the researchers (MAM and ZK) and a descriptive narrative summary was produced based on the survey questions.

Specific attention was given to overlooked issues and knowledge gaps, and any questions which could aid in potential future research

Results

This descriptive observational cross-sectional study on OHL, attitude and behaviour amongst the third-level students in UCC was conducted on a total of 1488 voluntarily participated students providing approximately 7% response rate.

Prevalence of OHL

The overall prevalence of limited health literacy (inadequate + marginal) was an alarmingly higher 77.9% in the study population (Table 1).

Table 1 Health literacy prevalence amongst the students in UCC in respect to age, gender and school; 2018
Full size table

Determinants of oral health literacy

The youngest age group (age 18–23 years) has significantly higher proportion of inadequate health literacy (8.1%) compared to other age groups (p = 0.038). Non-medical students had higher inadequate OHL (7.4%) compared to medical students (4.9%) (p = 0.081). Among the respondents in the inadequate health literacy category, 8.3% did not have a regular dentist (p = <0.001). Furthermore, among respondents with a good self-rated OHL, only 22.5% had adequate health literacy (p = 0.414). And among the respondents with adequate heath literacy, only 10.4% had better patient-dentist communication (p = <0.001). Finally, even if the respondents only had marginal health literacy, 94.4% had good self-rated oral health, 90.50% had better patient–dentist communication and 97% had good self-rated oral health attitude (Table 2).

Table 2 Characteristics of respondents to OHL; UCC, 2018
Full size table

Table 3 shows estimated Pearson correlation coefficients (‘r’) between oral health status and other potential correlates. OHL was significantly correlated with age (r = 0.104), school (r = − 0.130), frequency of dental visits (r = − 0.80) and the quality of dental-communications (r = − 0.413) but was not correlated with gender and parental education.

Table 3 Correlations among factors affecting oral health status of third-level students: Cork
Full size table

Additionally, one striking observation was the methods by which people access relevant health information and more than half the population relied on the internet for information regarding health.

Discussion

This is the first study in Ireland and other comparable populations to estimate prevalence of oral health literacy (OHL) among a student cohort in a university campus. One in four third-level university students reported an inadequate OHL of 23% and an overall prevalence of 77% limited OHL, which is higher compared to the general Irish population’s limited health literacy levels. The EU Health Literacy Survey (2012) revealed that of 10 Irish adults, 4 had limited HL [29].

Limited OHL levels are matters of concerns—both for the general public and for the policy-makers. Therefore, it is crucially important that both the health seekers and the health providers establish an effective communication at all levels of a health care system. In the context of this study, an effective patient-dentist communication is key to optimising health care services. The ‘Healthy Ireland - A Framework for Improved Health and Wellbeing 2013 – 2025’ is a key policy document whereby health literacy has been prioritised. Therefore, it is critical that limited oral health literacy levels are addressed adequately across the right stakeholders [30].

Moreover, as stated by Sharda et al. [31], there is a clear demarcation regarding OHL between students from medical and allied health and non-medical backgrounds. A significant difference in attitude was measured in students studying different disciplines [31]. Students pursuing a health-related discipline attain a formal education and quality information from teachers who have life experience of working as a health worker. They also have better understanding of medical terms and have a wealth of prior knowledge which provides them with a broader opportunity to attain higher OHL score. Although medicine and health students scored higher, it was still not a satisfying result, as the score was not optimal. It is clear that they could not convert their oral health information into sufficient use.

More than half of the study population accessed the internet to attain oral health–related information and this piece of information is vital to recognize the major shift the last decade has seen. But it also is tricky for the health care provider to ensure that the patient is capable to access credible and trustworthy sources.

Finally, a significant association between OHL and self-rated OH could not be established, conflicting with other studies [31], but this being a study on young students with a priori good health, this could have been a possibility of no association.

The study has both strengths and limitations

This is the first study undertaken in Ireland, on oral health literacy among third-level university students identifying prevalence of OHL in a university setting, and how it is correlated to other variables of interest.

Inherent methodological limitations of an online survey in relation to representativeness of the source population were present, as OHL includes ‘print literacy’ (reading and writing); ‘oral literacy’ speaking and listening; cultural and conceptual knowledge and numeracy. And this being a convenience online questionnaire study, it limited the possibility of any pronunciation or functional questions. Reporting bias, information bias, voluntary response bias and confounding could have been present. Furthermore, the very low response rate was a limiting factor, due to the current climate of ‘survey fatigue’. An estimated sample size calculation was done using OpenEpi [32]. No causal inference can be drawn (cross-sectional study).

Conclusions and recommendations

This study provides additional insights into third-level university students’ understanding of OHL and identifies potential areas for targeted interventions, for instance, incorporating health literacy in third-level educational curriculum. However, the study being cross-sectional, the results are to be interpreted with caution.

The study also indicates that the usage of the internet in health literacy and knowledge attainment is important. Following larger more representative longitudinal studies may help identify the need for comprehensibility of health materials and provide access to information less complex and more reliable. Developers of health information, health educators, dentists and policy-makers all need to work together to guarantee equality in accessing, understanding and usage of health information and especially for the next generation, collaborative efforts between teachers, education officials and dentists should prioritize the improvement of ‘functional health literacy’.

Internationally, health literacy has been recognized as an important attribute of global citizenship for determining right health decision-making and access to good health [33]. According to Healthy Ireland Implementation Plan, an action was called for promoting Health Literacy and implementing national tools for training [34]. Moreover, according to NALA (National Adult Literacy Agency), people aged 15–34 seldom asked to explain things they do not understand [35]. The general public also called for less medical jargon when being communicated to; therefore, it is of utmost importance to incorporate health literacy into the work of dentists and other oral health care professionals.