ABSTRACT
Background:
Oral cancer (OC) is the third most common malignancy in Saudi Arabia, following leukemia and lymphoma. Early detection of this disease is impacted by knowledge of OC. This study aimed to evaluate public awareness of OC in the Western Region of Saudi Arabia and investigate how demographic background characteristics influence this knowledge.
Methods:
In this cross-sectional study, a web-based questionnaire was distributed in a random multistage pattern between September 2023 and December 2023. The questionnaire was designed to measure knowledge levels of OC. A logistic regression model was used with demographic background variables as independent variables and knowledge of OC as the dependent variable.
Results:
Of 389 participants, only half were aware of OC (52.4%). Most participants (56%) had poor knowledge of OC, 37.3% had a moderate level of knowledge, and only 6.7% had good knowledge about OC. On multivariate analysis, higher level of education [(odds ratio (OR = 1.53; 95% confidence interval (CI): 1.27–1.79; P < 0.0001)], higher salary (OR = 1.29; 95% CI: 1.08–1.49; P < 0.0001), and being a female (OR = 1.28; 95% CI: 1.09–1.46; P = 0.011), were positively associate with the general knowledge of OC.
Conclusion:
Nearly one in every two residents in the western region of Saudi Arabia has never heard of OC. Most of the participants had poor knowledge of OC. Socioeconomic factors, including income and educational level, were the most prominent factors affecting the general understanding of OC. Community-level educational programs focusing on high-risk groups could increase awareness about OC and improve public health.
Keywords: Oral cancer, awareness, knowledge, sociodemographic characteristics
Introduction
Oral cancer (OC) is defined as a malignant growth affecting the oral cavity that extends from the lips to the front pillars of the fauces, which is mainly correlated with alcohol and tobacco use.[1] With an incidence of more than 300,000 cases annually, OC is reportedly the eighth most prevalent cancer diagnosed worldwide.[2,3] In Saudi Arabia, OC is regarded as the third most common malignancy, only after leukemia and lymphoma.[4] Compared to developed countries, the incidence and mortality of OC are higher in developing nations.[2,5] Because OC is frequently preceded by a pre-cancer stage that may be detected through examination, early detection and diagnosis of OC helps to reduce mortality and morbidity. Most study findings indicate that screening should be done continuously to identify OC.[6,7]
The prevalence of OC in Saudi Arabia ranges from 21.6% to 68.6%.[3] Thus, OC is considered a significant public health issue in the country.[4] Because of the impact of OC on public health, it is essential to promote early screening and raise general knowledge of the illness, its clinical manifestations, and risk factors.[8]
One study conducted in Jazan province in Saudi Arabia concluded that there needs to be more sufficient knowledge about early signs and treatment options for OC.[7] Another study conducted across private dental colleges in Saudi Arabia indicated the need to reinforce undergraduate knowledge, particularly in prevention and early detection.[9] Although similar studies have been conducted in different parts of Saudi Arabia, they have yet to assess the knowledge about OC in the country’s western region. We aim to fill this gap and establish a baseline for this matter, as similar information can identify which high-risk group can benefit most from raising awareness of OC regarding its sources, prevention, and potentially harmful effects.
Methods
Study design and setting
After receiving ethical approval from our center’s Institutional Review Board (IRB), we conducted a cross-sectional, web-based survey to assess the knowledge of OC among adults who reside in the western region of Saudi Arabia.
Study duration
The study was conducted between September and December 2023.
Sample size and sampling
All participants are residents of the region west of Saudi Arabia aged 18 years or older. The sample size for this study was estimated to be 385 participants based on a sample size formula for a cross-sectional study design. The margin of error selected was 0.05 with a 95% confidence level, as calculated by Raosoft.[10] The sample size n and margin of error E are given by
x = Z (c/100) 2r (100–r)
n = Nx/((N–1) E2 + x)
E = Sqrt [(N–n) x/n (N–1)]
Where N is the size of the population, r is the percentage of replies, and Z (c/100) is the critical value for the confidence level c.[10]
Data collection
We used the Snowball technique, wherein we encouraged a group we know to distribute copies of the internet survey to their contacts.[11]
Study outcomes and tools
The primary objective of the study was to determine the association between the individual’s demographic characteristics in western Saudi Arabia and their knowledge of OC. We used an Arabic 30-item web-based questionnaire similar to previous studies.[7,12] The first nine questions in the survey addressed demographic background variables; item 10 asked whether the participants had heard of OC. Items 11–14 concentrated on the general information of OC; items 15–20 assessed risk factor awareness; items 21–24 assessed OC symptom awareness; and items 25–30 set knowledge of OC treatments and outcomes. For all items except items 1–9, 14, and 15, a score of 1 was given for correct answers and a zero when the participants indicated that they did not know or chose an incorrect answer, allowing for a maximum score of 19. Scores were added to obtain a total knowledge score for each participant, ranging from 0 to 19. Scores of < 10 (below the median) were considered to indicate a low level of knowledge, scores of 10–15 to display a moderate level of knowledge (representing the third quartile of data), and scores > 15 to indicate a high level of knowledge (representing the upper quartile).
Data analysis
The Statistical Package for Social Sciences (SPSS) version 21 was used for statistical data entry and analysis. Descriptive and inferential statistics were used in data analysis, depending on the intended outcome of each relationship. Data with a normally distributed distribution were handled by tests like the t-test and analysis of variance (ANOVA) test. Whereas continuous data were shown as means and standard deviations, all categorical variables were displayed as frequencies and percentages. Using the Chi-square test, the relationship between two category variables was examined. The threshold for statistical significance was set at P < 0.05. Variables with significant relationships in univariate analysis were employed in multivariate analysis.
Ethical consideration
The first page of the questionnaire contained a statement outlining the study’s significance and goals. This statement was used to obtain informed permission before allowing participants to continue with the questionnaire. Each participant signed a commitment that their information would be kept confidential, and all data submitted was utilized only for the study.
Our hospital’s IRB approved this study.
Results
Three hundred eighty-nine respondents completed our survey. The participants’ demographic information is displayed in Table 1. The majority of participants (72.2%) were over the age of 39. Males make up 62.5% of our sample. Moreover, Saudis made up 91.8% of the study’s participants. Furthermore, 66.6% of the study participants were married. Regarding educational attainment, 80.7% of the subjects completed their university education or above. Furthermore, 97.2% of the participants lived in a city. Among the survey participants, a quarter were unemployed; 43.4% held government employment, 15.7% had private sector positions, and 14.9% were students. Regarding monthly pay, 58.1% of the participants had a salary of 10,000 SAR or higher.
Table 1.
Sociodemographic characteristics of participants (n=389)
| Characteristic | Frequency | Percentage |
|---|---|---|
| Age | ||
| 18–30 | 108 | 27.8 |
| 31–45 | 114 | 29.3 |
| 46–60 | 105 | 27.0 |
| >60 | 62 | 15.9 |
| Gender | ||
| Male | 243 | 62.5 |
| Female | 114 | 37.5 |
| Nationality | ||
| Saudi | 357 | 91.8 |
| Non–Saudi | 32 | 8.2 |
| Marital status | ||
| Single | 107 | 27.5 |
| Married | 259 | 66.6 |
| Divorced or widowed | 23 | 16 |
| Place of living | ||
| City | 378 | 97.2 |
| Village | 11 | 2.8 |
| Education level | ||
| Primary | 3 | 0.8 |
| Intermediate | 7 | 1.8 |
| Secondary | 65 | 16.7 |
| University | 245 | 63.0 |
| Postgraduate higher education | 69 | 17.7 |
| Occupation | ||
| Student | 58 | 14.9 |
| Government | 169 | 43.4 |
| Private | 61 | 15.7 |
| Unemployed | 101 | 26.0 |
| Marital status | ||
| <5000 SAR monthly | 62 | 15.9 |
| 5000–10,000 SAR monthly | 101 | 26.0 |
| >10,000 SAR monthly | 226 | 58.1 |
| City | ||
| Makkah | 174 | 44.7 |
| Jeddah | 173 | 44.5 |
| Taif | 13 | 3.3 |
| Khulays | 1 | 0.3 |
| Bahrah | 28 | 7.2 |
As shown in Table 2, only half of the participants were aware of the disease (52.4%). Almost half of the participants perceive OC as a preventable disease (57.6%). Similarly, 55.3% believed that OC is a curable disease. Furthermore, the majority think that OC is not contagious.
Table 2.
Study participants’ awareness of general information about oral cancer
| Items | Yes | No | I do not know |
|---|---|---|---|
| Have you heard of oral cancer? | 204 (52.4%) | 185 (47.6%) | 0 (0%) |
| Do you think oral cancer is a preventable disease? | 224 (57.6%) | 9 (2.3%) | 156 (40.1%) |
| Do you think that oral cancer is a disease that can be cured? | 215 (55.3%) | 9 (2.3%) | 165 (42.4%) |
| Do you think that oral cancer is a contagious disease to others? | 48 (12.3%) | 175 (45%) | 166 (42.7%) |
As shown in Table 3, 43.4% of the participants visited their dentist once annually. Furthermore, mass media was shown to be the primary source of information about OC, followed by family and friends.
Table 3.
Information on study participants’ visit to the dentist and their source of information on oral cancer
| Items | Frequency | Percentage |
|---|---|---|
| How often do you go to the dentist? | ||
| Less than 3 months | 22 | 5.7 |
| Every 3–6 months | 90 | 23.1 |
| Every 1 year | 108 | 27.8 |
| More than 1 year | 169 | 43.4 |
| What is the source of your information about oral cancer? | ||
| Mass media | 272 | 69.9 |
| Dentist | 19 | 4.9 |
| Family physician | 22 | 5.7 |
| Family or friends | 76 | 19.5 |
Regarding risk factors awareness, the majority did not know whether family history increases the risk of OC. Most participants, however, were able to identify smoking, sniffing, alcoholism, and aging as risk factors for OC [Table 4].
Table 4.
Study participant’s awareness of risk factors for oral cancer
| Items | Yes | No | I do not know |
|---|---|---|---|
| Do you think that positive family history is a risk factor for oral cancer? | 148 (38%) | 67 (17.2%) | 174 (44.7%) |
| Do you think that smoking is a risk factor for oral cancer? | 321 (82.5%) | 13 (3.3%) | 55 (14.1%) |
| Do you think that sniffing is a risk factor for oral cancer? | 329 (84.6%) | 7 (1.8%) | 53 (13.6%) |
| Do you think that drinking alcohol is a risk factor for oral cancer? | 251 (64.5%) | 39 (10%) | 99 (25.4%) |
| Do you think that exposure to sunlight is a risk factor for oral cancer? | 55 (14.1%) | 153 (39.3%) | 181 (45.5%) |
| Do you think that the incidence of oral cancer increases with age? | 207 (53.2%) | 182 (46.8%) | 0 (0%) |
Table 5 presents the participants’ awareness of the signs and symptoms of OC. Most participants (71.2%) indicated that lumps could signify OC.
Table 5.
Study participant’s awareness of symptoms of oral cancer
| Items | Yes | No | I do not know |
|---|---|---|---|
| Do you think that a chronic mouth ulcer may be a sign of oral cancer? | 153 (39.3%) | 42 (10.8%) | 194 (49.9%) |
| Do you think that the presence of red spots in the mouth is a sign of oral cancer? | 92 (23.7%) | 61 (15.7%) | 236 (60.7%) |
| Do you think that the presence of white spots in the mouth is a sign of oral cancer? | 84 (21.6%) | 69 (17.7%) | 236 (60.7%) |
| Do you think that a lump in the mouth or the neck is a sign of oral cancer? | 277 (71.2%) | 112 (28.8%) | 0 (0%) |
Regarding treatment awareness of OC, most participants indicated that oral self-examination could help early detection of OC. Furthermore, the majority thought that early detection of OC improves the outcomes. Additionally, most participants reported that there are various approaches to treat OC, including radiation therapy and chemotherapy [Table 6].
Table 6.
Study participants’ treatment and outcomes of oral cancer test
| Items | Yes | No | I do not know |
|---|---|---|---|
| Do you think that oral self-examination helps to detect oral cancer early? | 233 (59.9%) | 49 (12.6%) | 107 (27.5%) |
| Do you think that when oral cancer is detected early, it can be cured? | 318 (81.7%) | 4 (1%) | 67 (17.2%) |
| Do you think that when oral cancer is detected, surgery is the best option to limit and treat its spread? | 161 (41.4%) | 29 (7.5%) | 199 (51.2%) |
| Do you think that when oral cancer is detected, preventive radiotherapy limits its spread and treats it? | 183 (47%) | 9 (2.3%) | 197 (50.6%) |
| Do you think that when oral cancer is detected late, chemotherapy will be used? | 179 (46%) | 13 (3.3%) | 197 (50.6%) |
Regarding factors affecting the knowledge of OC, significant factors included gender (P = 0.001), educational level (P = 0.001), salary (P = 0.04), and information source (P = 0.002). [Table 7]
Table 7.
Univariate analysis of factors associated with the knowledge of OC
| Variable | Poor knowledge (n, %) | Moderate knowledge (n, %) | Good knowledge (n, %) | P |
|---|---|---|---|---|
| Age in years (n, %) | ||||
| 18–30 | 53 (24.3) | 47 (32.4) | 8 (30.8) | 0.06 |
| 31–45 | 58 (26.6) | 46 (31.7) | 10 (38.5) | |
| 46–60 | 61 (28) | 38 (26.2) | 6 (23.1) | |
| >60 | 46 (21.1) | 14 (9.7) | 2 (7.7) | |
| Gender (n, %) | ||||
| Male | 152 (69.7) | 74 (51) | 17 (65.4) | 0.001 |
| Female | 66 (30.3) | 72 (49) | 9 (34.6) | |
| Marital status (n, %) | ||||
| Single | 149 (68.3) | 93 (64.1) | 17 (65.4) | 0.43 |
| Married | 53 (24.3) | 46 (31.7) | 8 (30.8) | |
| Divorced or widowed | 16 (7.3) | 6 (4.1) | 1 (3.8) | |
| Monthly Salary (SAR) | ||||
| <5000 | 36 (16.5) | 26 (17.9) | 0 (0) | 0.04 |
| 5000–10,000 | 65 (29.8) | 30 (20.7) | 6 (23.1) | |
| >10,000 | 117 (53.7) | 89 (61.4) | 20 (76.9) | |
| Educational level (n, %) | ||||
| Primary | 3 (1.4) | 0 (0) | 0 (0) | 0.001 |
| Intermediate | 4 (1.8) | 3 (2.1) | 0 (0) | |
| Secondary | 61 (28) | 38 (26.2) | 6 (23.1) | |
| University | 46 (21.1) | 14 (9.7) | 2 (7.7) | |
| Postgraduate higher education | 23 (10.6) | 35 (24.1) | 11 (42.3) | |
| Nationality (n, %) | ||||
| Saudi | 195 (89.4) | 136 (93.8) | 26 (100) | 0.09 |
| Non-Saudi | 23 (10.6) | 9 (6.2) | 0 (0) | |
| Residence | ||||
| City | 210 (96.3) | 142 (97.9) | 26 (100) | 0.44 |
| Village | 8 (3.7) | 3 (2.1) | 0 (0) | |
| Source of information (n, %) | ||||
| Mass media | 164 (75.2) | 93 (64.1) | 15 (57.7) | 0.002 |
| Dentist | 8 (3.7) | 8 (5.5) | 3 (11.5) | |
| Family physician | 5 (2.3) | 12 (8.3) | 5 (19.2) | |
| Family or friends | 41 (18.8) | 32 (22.1) | 3 (11.5) | |
| Dentist visits frequency (n, %) | ||||
| Less than 3 months | 8 (3.7) | 13 (9) | 1 (3.8) | 0.45 |
| Every 3–6 months | 8 (3.7) | 8 (5.5) | 3 (11.5) | |
| Every 1 year | 64 (29.4) | 36 (24.8) | 8 (30.8) | |
| More than 1 year | 48 (22) | 36 (24.8) | 6 (23.1) |
On multivariate regression analysis, significant factors were female gender [odds ratio (OR) =1.28; 95% confidence interval (CI): 1.09–1.46; P = 0.011], higher educational level (OR = 1.53; 95% CI: 1.27–1.79; P < 0.0001), and higher salary (OR = 1.29; 95% CI: 1.08–1.49; P < 0.0001).
Discussion
This study aimed to evaluate the public awareness regarding OC in the western region of Saudi Arabia and investigate how demographic characteristics influenced knowledge levels. Although most of our sample size had higher levels of education (university and above), multivariate regression analysis showed that educational level was associated with the highest odds ratio in predicting knowledge of OC. Other studies have reported similar results.[13,14,15,16,17] Conversely, Comunian et al.,[18] and Tarkaji et al.,[9] observed no statistically significant correlation between education and OC knowledge levels. Yet both studies only looked at university faculty, students, and administrative personnel, who all had high baseline levels of schooling with moderate to good knowledge about OC. These findings signify the importance of education, as it can improve public health standards. The findings also highlight the importance of enhancing awareness among those with lower levels of education.
The present study revealed an association between income and knowledge of OC. The higher the income, the higher the score for OC knowledge. Other studies showed similar results, as lower-income people have lower insights about OC.[19,20,21] In previous studies, lower socioeconomic status has been linked with an increased incidence of OC.[20,22] People of lower education levels and lower income have more deficient baseline knowledge of OC, exposing them to more risk factors as they do not know how harmful they can be, which increases the incidence of OC among this group. Awareness of OC is needed among all populations, with a particular focus on a high-risk group.
In our study, females were more knowledgeable about OC than males. Although this was statistically significant, the effect of gender on the knowledge levels was minor (odds ratio = 1.28). Similarly, Oh et al. [13,15,23,24,32] observed that males were just slightly more knowledgeable than females (odds ratio = 1.2), suggesting that the effect of gender on knowledge levels was negligible. In contrast, many studies denied any associations between gender and knowledge levels about OC.
Regardless of socioeconomic backgrounds, most of the participants in our study showed good knowledge about common risk factors of OC, including drinking alcohol and tobacco use in its different forms. Similar findings were reported in previous studies.[7,25] Besides the religious background of our population, these results, too, can be attributed to the strategies implemented by the government of Saudi Arabia, which centers on raising taxes and using visuals and graphics to highlight the detrimental consequences of substance use.[7] Nevertheless, most of our sample needed more knowledge about important risk factors and clinical manifestations of OC. Excessive sunlight exposure is a well-known risk factor for oral squamous cell carcinoma.[26,27] In our study, only 14.1% were able to identify sunlight exposure as a risk factor for OC. Other studies in different parts of the world showed similar percentages.[21,28] Furthermore, only one-third of our sample thought that family history increases the risk of OC. Without a doubt, these numbers are alarming. The western region of Saudi Arabia is a coastal area; residents of this region are at higher risk as they are more frequently exposed to sunlight than other central areas of Saudi Arabia. Approximately half of the participants did not identify chronic mouth ulcers and oral leukoplakia as potential clinical manifestations of OC. Similar results were reported in other studies.[29,30,31] A delayed or incorrect diagnosis may result from ignorance of the familiar and early symptoms of OC. Treatment may be postponed as a result, which can impact the survival of OC patients. Measures must be taken to improve the public’s knowledge about these risk factors, as this may be a primary step towards decreasing the incidence of OC in our locality.
This study revealed a high-risk population that could benefit from improving their general knowledge of OC. Although this study was performed on a relatively large sample, our findings need to be interpreted with the following limitations in mind: First, the cross-sectional nature of the study, as longitudinal studies are more appropriate and can provide more robust evidence. Second, although our study aimed to assess the knowledge of OC among adult residents of western Saudi Arabia, most of the participants resided in two large cities, which can create grounds for selection bias. Third, the questionnaire used in the study was not validated to determine the OC knowledge.
Conclusion
Approximately half of the residents in the western region of Saudi Arabia have never heard of OC. The majority of the participants had poor knowledge of OC. Socioeconomic factors, including higher income and educational level, were the most significant factors affecting the general understanding of OC. Community-level educational programs focusing on high-risk groups could increase awareness about OC and improve public health.
Ethics declarations
All patients signed an informed written consent for their contribution to the research (collecting and publishing data) before any data collection. The study was approved by the Biomedical Ethics Research Committee at King Abdulaziz University, Jeddah, Saudi Arabia, and was conducted in accordance with the ethical standards of the Declaration of Helsinki.
Conflicts of interest
There are no conflicts of interest.
Acknowledgments
The authors acknowledge the permission granted by other consultants to enroll their patients in the study.
Funding Statement
Nil.
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