Abstract
Objectives:
To investigate individuals’ knowledge about central nervous system tumors (CNST) signs and symptoms and risk factors, as well as their readiness to seek medical advice. The signs and symptoms associated with CNSTs are often vague, and failure to recognize them could lead to delays in seeking help and possibly fatal results.
Methods:
This was a cross-sectional survey that utilized 2 delivery methods. A total of 1,500 personally delivered and 1,500 online self-administered questionnaires were completed in parallel between June 2015 and June 2016 for the occupants of the Kingdom of Saudi Arabia.
Results:
Significant differences were observed for the sociodemographic characteristics of participants recruited via the 2 methods. The most recognized symptom was “Headaches” (45.2%), and the most recognized risk factor was “Radioactive location/occupation” (84.1%). Overall knowledge scores were low, significantly predicted by employment and cancer contact (p<0.05), while the scores significantly higher for participants who were willing to see their doctors within a week (p<0.005). The most recognized barrier to seeking help was “Worry about what the doctor might find” (74.0%).
Conclusion:
The level of awareness of CNSTs was low. Using a questionnaire delivered in 2 different ways enabled the recruitment of sample pools with different sociodemographic characteristics.
For many health-related issues, awareness is considered an important factor associated with behavior.1 Several studies have linked high knowledge to the ability to address modifiable associated causes, for instance, improving diet and increasing exercise to prevent cancer, as well as taking appropriate actions in response to detecting associated symptoms.2 Assessing the level of public awareness of health-related issues is important for identifying deficient areas and increasing awareness in areas where needed.3 The occurrence of a central nervous system tumor (CNST) in any individual, with its associated consequences, is a devastating event.4 In 2012, the World Health Organization (WHO) Global Cancer report (GLOBOCAN) stated that more than 250,000 individuals worldwide were diagnosed with a CNST, and approximately 190,000 died, ranking CNSTs in the top 10 mortalities caused by cancer.5,6,7 More than 120 CNST entities have been classified by the World Health Organization (WHO) based on their clinicopathological characteristics and histological patterns.8 The signs and symptoms for CNSTs depend on the tumor location, and they are not exclusively indicative of the presence of these tumors.3,9,10 Causes associated with the development of CNSTs vary, and many are still under investigation.11-20 Many studies that assess health public awareness rely on random sampling through telephone directories, a system that is not necessarily available in many developing countries. Questionnaires provided online have frequently been used, including in marketing research and psychological studies. Due to their attractive ability to access larger cohorts and improve validation checks, and thus data quality, these Web-based questionnaires represent an important tool for many epidemiological studies on public health.21,22 Awareness of the symptoms and risk factors for CNSTs is especially critical, since the disease signs tend to be vague and easily overlooked, resulting in a delayed response to take appropriate action. Unfortunately, there is a lack of CNST awareness studies that assess the level of public understanding in many regions of the world. In this study, we aimed to investigate the knowledge concerning CNST signs and symptoms and risk factors, as well as readiness to seek medical advice, among citizens of the Kingdom of Saudi Arabia (KSA) using 2 questionnaire delivery methods.
Methods
Subjects and study design
This was a cross-sectional survey using 2 delivery methods, distributed in parallel between June 2015 and June 2016. Personally delivered self-administered questionnaires were distributed (1,752 forms) until 1,500 occupants of Jeddah, KSA, completed the forms. A nonprobability sampling technique was used to recruit participants from the local university and its local hospital, families and friends of participating students, workers, and customers visiting local markets and no exclusion criteria of the participants was applied. This sample size provided a confidence level of 95%, with a confidence interval (CI) of 2.53%, for a population size of 3,976,000 people in Jeddah, as reported in Statistical Yearbook 50 (2014) published by the Central Department of Statistics and Information.23 Fourth-year applied medical sciences students were involved in recruiting participants, and they were trained prior to delivering the questionnaire. The same questionnaire was activated online in Arabic.The questionnaire was advertised through Twitter, Instagram, and email. The participants were recruited until 1,500 self-administered questionnaires were completed. This number was chosen to allow for statistical comparisons with the personally delivered questionnaires.
Questionnaire items
The structure and items for the questionnaire were developed in English based on the Cancer Awareness Measure (CAM) and information in the literature for CNST-specific symptoms and risk factors, as mentioned above.24 The items were then translated into Arabic, and the questionnaires were made available in both languages for the participants to choose from. All items were reviewed by 2 neuro-oncologists to ensure relevance and accuracy. The participants were not allowed to rewrite their recall items once they proceeded to the next question. The items included the following:
Section 1
This section comprising the 2 following questions, addressed the participants knowledge about the CNST warning signs and symptoms: Question 1) An open, unprompted warning sign question: “Would you please name as many early warning signs of CNST as you can think of?”; Question 2) A closed, prompted warning sign question: “Can you state whether you think any of these are warning signs of CNST? Do you think X could be a sign/symptom of CNST?” Here, X was one of 19 signs/symptoms, namely headaches, not eating or having a poor appetite, loss of weight, vomiting without diarrhea, experiencing abnormal involuntary movements, loss of bladder/bowel control, drowsiness or prolonged sleepiness, back pain or stiffness, odd posture, unusual head tilt or stiff neck, arm paralysis, monoplegia, muscle weakness, visual impairment, deafness, excessive emotional problems, behavioral problems, personality change, constant confusion, and clumsiness or loss of balance. For children, further symptoms were mentioned, such as congenital anomaly of the brain, enlarged head development, physical delay, and difficulty in awareness and learning. For this prompted question, the response options were “Yes”/“No”/“Don’t know”.
Section 2
This section addressed barriers to seeking help and was composed of the 2 following questions: Question 3) An open, unprompted question on help-seeking behavior: “If you had a symptom that you thought might be a sign of a CNST, how soon would you contact your doctor to make an appointment to discuss it?”; Question 4) A closed, prompted question on barriers to seeking help: “Sometimes, people put off going to see the doctor, even when they have a symptom that they think might be serious. Could you say if any of these might put you off going to the doctor?” Ten options from CAM were included, and for this closed question, the response options were “Yes, often”/“Yes, sometimes”/“No”/“Don’t know”.
Section 3
This section composed of the 2 following questions, addressed knowledge of possible risk factors: Question 5) An open, unprompted risk factor question: “What do you think affects a person’s chance of developing a CNST?”; Question 6) A closed, prompted risk factor question: “These are some of the factors that can increase a person’s chance of developing a CNST. How much do you agree that each of the listed factors can increase a person’s chance of developing a CNST?” A list of 13 items was provided, including being over 70 years old, lack of regular exercise, being overweight (body mass index [BMI] over 25), regular exposure to radiation/X-rays or computed tomography (CT) scans, exposure to pesticides, prolonged poor diet, infections, repetitive and prolonged exposure to mobile phones, and familial and syndromic genetic factors. For this prompted question, the response options were given on a 5-point Likert agreement scale (“Strongly agree” to “Strongly disagree”).
Section 4
This final section that was designed following CAM, was composed of a set of questions on sociodemographic characteristics, including age, gender, location/residence, ethnicity, marital status, main language, education, employment, and a CNST contact.
Scoring of items
The items were scored in the following manner: 1) Unprompted items: For knowledge of signs and symptoms (Q1) and risk factors (Q5), 1 mark was given for unprompted items that also appeared in the corresponding prompt list. For the seeking help open question (Q3), the results were scored on a scale of 1-10 (Immediately=10, 1-3 days/as soon as possible=9, 4-6 days=8, 1 week=7, 2 weeks=6, 1 month=5, 6 weeks=4, 3 months=3, 6 months=2, 12 months=1, Never/don’t know/unanswered=0); and 2) Prompted items: For the signs and symptoms prompted items (Q2), the responses “No” and “Don’t Know” were scored as 0, with a score of 1 given for each “Yes” response, allowing a maximum possible score of 19. For the risk factor prompted items (Q6), “Not sure,” “Disagree,” and “Strongly disagree” responses were scored as 0, while “Strongly agree” or “Agree” responses were scored as 1, allowing a maximum possible score of 13. The total knowledge score was calculated as the sum of the scores for both questions, giving a maximum possible score of 32. For Q4, each item with responses of “Yes, often” or “Yes, sometimes” was given a score of 1, while item responses of “No”/“Don’t know” or unanswered items were given a score of 0.
Reliability
The Cronbach’s alpha coefficient for a pretest analysis for 95 participants for Q2 and 6 was 0.743. Following the collection of all 1,500 personally delivered questionnaires, the reliability coefficient (Cronbach’s alpha) for Q2 was 0.760, while it was 0.728 for Q6 and 0.771 for both. For the online survey, the reliability coefficient (Cronbach’s alpha) for Q2 was 0.791, while it was 0.859 for Q6 and 0.833 for both.
Data analysis
An identification number was given for each completed questionnaire. The data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 21.0 (IBM Corp., Armonk, NY, USA) to generate descriptive and inferential statistics, which were used as appropriate. For the sociodemographic characteristics, the data were expressed using frequencies and percentages, and the significance between the groups was calculated using the Pearson chi-square test of independence. Differences between item selections were tested using the chi-square test for independence, with Yates continuity correction. Differences in the knowledge scores obtained within groups were compared using analysis of variance (ANOVA) robust tests of equality of means, and p-values for Welch and Brown-Forsythe were indicated. A model of multiple regression analysis was employed to examine the influence of all the sociodemographic characteristics on the total knowledge scores, and missing values were excluded in a pairwise manner. Univariate general linear models (GLMs) that included all participants were used to determine the effects of the delivery method on the knowledge scores while adjusting for sociodemographic factors.
Results
The sociodemographic characteristics of all participants are shown in Table 1. Apart from region and ethnic grouping, there were significant differences between the frequencies in each subgroup when comparing the 2 participant pools, as determined by Pearson’s chi-square test of independence. However, the proportions of subgroups within the categories were similar. Compared with the personally delivered method, the sociodemographic characteristics of participants recruited via the online method exhibited a higher number of younger participants (4.6% in person, 13.9% online; mean age: 27.2 years in person, 25.2 years online), females (61.7% in person, 80.5% online), participants who were mostly unemployed (49.2% in person, 72.0% online), and participants who had no CNST contact (63.5% in person, 70.3% online). A similar number of participants in both methods had at least one sociodemographic item undeclared (441 participants [29.4%] in person, 440 participants [29.3%] online).
Table 1.
Sociodemographic characteristics of all participants.
| Characteristics | All participants | Personally delivered | Provided online | χ2 |
|---|---|---|---|---|
| n (%) | ||||
| Age group | ||||
| <18 | 277 (9.2) | 69 (4.6) | 208 (13.9) | 80.84* |
| 18-39 | 2318 (77.3) | 1142 (76.1) | 1176 (78.4) | |
| 40+ | 291 (9.0) | 178 (11.9) | 113 (7.5) | |
| Not declared | 114 (3.8) | 111 (7.4) | 3 (0.2) | |
| Gender | ||||
| Male | 781 (26.0) | 552 (36.8) | 229 (15.3) | 170.306* |
| Female | 2134 (71.1) | 926 (61.7) | 1208 (80.5) | |
| Not declared | 85 (2.8) | 22 (1.5) | 63 (4.2) | |
| Region | ||||
| Riyadh | 476 (15.9) | 0 0 | 476 (31.7) | 1189.797* |
| Jeddah | 2145 (21.5) | 1500 (100) | 645 (43) | |
| South | 72 (2.4) | 0 0 | 72 (4.8) | |
| North | 72 (2.4) | 0 0 | 72 (4.8) | |
| East | 189 (6.3) | 0 0 | 189 (12.6) | |
| Outside KSA | 40 (1.4) | 0 0 | 40 (2.7) | |
| Not declared | 6 (0.2) | 0 0 | 6 (0.4) | |
| Ethnic group | ||||
| Arab | 2251 (75.0) | 1094 (72.9) | 1157 (77.1) | 0.682 |
| Other | 126 (4.2) | 66 (4.4) | 60 (4.0) | |
| Not declared | 623 (20.8) | 340 (22.7) | 283 (18.9) | |
| Language | ||||
| Arabic | 2907 (96.9) | 1423 (94.9) | 1484 (98.9) | 24.187 |
| English | 47 (1.6) | 40 (2.7) | 7 (0.5) | |
| Not declared | 46 (1.5) | 37 (2.5) | 9 (0.6) | |
| Marital status | ||||
| Single | 1745 (58.2) | 851 (56.7) | 894 (59.6) | 8.638* |
| Married | 1131 (37.7) | 615 (41.0) | 516 (34.4) | |
| Not declared | 124 (4.1) | 34 (2.3) | 90 (6.0) | |
| Highest level of education | ||||
| None | 21 (0.7) | 14 (0.9) | 7 (0.5) | 25.608* |
| <University | 1010 (33.7) | 497 (33.1) | 513 (34.2) | |
| ≥University | 1894 (63.1) | 943 (62.9) | 951 (63.4) | |
| Other | 23 (0.8) | 23 (1.5) | 0 (0.0) | |
| Not declared | 52 (1.7) | 23 (1.5) | 29 (1.9) | |
| Work status | ||||
| Employed | 1107 (36.9) | 733 (48.9) | 374 (24.9) | 180.668* |
| Unemployed | 1818 (60.6) | 738 (49.2) | 1080 (72.0) | |
| Not declared | 75 (2.5) | 29 (1.9) | 46 (3.1) | |
| CNST contact | ||||
| Yes | 893 (29.8) | 471 (31.4) | 422 (28.1) | 6.908* |
| No | 2006 (66.9) | 952 (63.5) | 1054 (70.3) | |
| Not declared | 101 (3.40) | 77 (5.1) | 24 (1.6) | |
CNST - Central nervous system tumor, KSA - Kingdom of Saudi Arabia. Pearson Chi-Square test for independence comparing characteristics for participants recruited via the personally delivered verses the online provided method.
represents significance p<0.05
Responses to signs and symptoms items and risk factors
On average, the participants responded to 99.6% of the items on the personally delivered questionnaires, while those who responded online completed 100% of the items (Appendices 1, 2, and 3). The data analysis for all the participants indicated significant differences between the recall and recognition responses (Table 2). The most recalled items were “Headaches” (45.2%), “Drowsiness or prolonged sleepiness” (22.1%), and “Difficulty in awareness and learning” (18.7%); in contrast, the most recognized items were “Headaches” (85.2%), “Abnormal involuntary movements” (84.6%), and “Clumsiness/loss of balance” (79.5%). The average score for the recognition items for the participants was significantly higher than the average score for recall (1.9±1.8 recall, 9.4±3.5 recognition, p<0.001).
Table 2.
Frequencies of participants’ agreements with statements associated with the signs and symptoms or risk factors for central nervous system tumors.
| Factor | All Participant | ||
|---|---|---|---|
| Recall | Recognition | χ2a | |
| n (%) | |||
| Signs and symptoms | |||
| Headaches | 1355 (45.2) | 2555 (85.2) | 1059.96* |
| Drowsiness or prolonged sleepiness | 663 (22.1) | 1700 (56.7) | 756.51* |
| Difficulty in awareness and learning | 560 (18.7) | 1702 (56.7) | 927.35* |
| Arm paralysis, muscle weakness | 520 (17.4) | 1550 (51.7) | 783.91* |
| Visual impairment | 466 (15.5) | 1924 (64.1) | 1486.99* |
| Abnormal involuntary movements | 407 (13.6) | 2538 (84.6) | 3035.04* |
| Back pain, back stiffness, odd posture | 384 (12.8) | 1066 (35.5) | 423.37* |
| Vomiting without diarrhea | 307 (10.2) | 1086 (36.2) | 567.74* |
| Clumsiness/loss of balance | 305 (10.2) | 2386 (79.5) | 2921.82* |
| Loss of weight | 169 (5.6) | 1644 (54.8) | 1718.13* |
| Not eating or having a poor appetite | 162 (5.4) | 1674 (55.8) | 1801.30* |
| Deafness | 109 (3.6) | 1507 (50.2) | 1654.32* |
| Excessive emotional problems | 102 (3.4) | 701 (23.4) | 515.36* |
| Enlarged head development | 97 (3.2) | 1435 (47.8) | 1572.42* |
| Behavior problems, personality change | 94 (3.1) | 710 (23.7) | 545.48* |
| Unusual head tilt or stiff neck | 29 (0.97) | 1441 (48.0) | 1796.03* |
| Congenital anomaly of brain | 19 (0.6) | 1126 (37.5) | 1324.35* |
| Physical delay | 9 (0.3) | 1133 (37.8) | 1365.98* |
| Loss of bladder/bowel control | 8 (0.3) | 435 (14.5) | 443.91* |
| Average score (SD) out of 19 | 1.92 (± 1.8) | 9.44 (± 3.53) | p=0.000 |
| Risk factors | |||
| Radioactive location/occupation | 713 (23.8) | 2524 (84.1) | 2206.50* |
| Close relative with CNST | 469 (15.6) | 1454 (48.5) | 778.31* |
| Low physical activity | 186 (6.2) | 737 (24.6) | 413.52* |
| Repetitive long periods of exposure to mobile phones | 158 (5.3) | 1976 (65.9) | 2424.47* |
| Low fruit and vegetable intake | 288 (4.8) | 760 (12.7) | 256.48* |
| Frequent exposure to bisphenol A | 109 (3.6) | 1956 (65.2) | 2530.19* |
| Red/processed meat | 216 (3.6) | 650 (10.8) | 257.28* |
| Frequent exposure to dental X-rays | 79 (2.6) | 1294 (43.1) | 1409.94* |
| Exposure to computed tomography (CT) scans | 45 (1.5) | 1390 (46.3) | 1671.51* |
| Infection | 43 (1.4) | 580 (19.3) | 569.11* |
| Overweight (body mass index [BMI] over 25) | 40 (1.3) | 938 (31.3) | 998.31* |
| Exposure to pesticides | 36 (1.2) | 2117 (70.6) | 3149.27* |
| Over 70 years of age | 25 (0.8) | 1069 (35.6) | 1239.57* |
| Average score (STD) out of 13 | 0.80 (± 1.04) | 5.82 (± 3.04) | p=0.000 |
*Chi-Square test for independence with yates continuity correction. *represents significance p<0.05, *P-values for ANOVA Welch and Brown-Forsythe
The most recalled risks were “Radioactive location/occupation” (23.8%), “Close relative with CNST” (15.6%), and “Low physical activity” (6.2%), while the most recognized items were “Radioactive location/occupation” (84.1%), “Exposure to pesticides” (70.6%), and “Repetitive long periods of exposure to mobile phones” (65.9%). The average score for the recognition items was significantly higher than the average score for recall (0.8±1.0 recall, 5.8±3.0 recognition, p<0.001).
Sociodemographic factors that may influence total knowledge scores
The average overall knowledge score for the recognized items for all the participants was 15.3±5.3 out of 32 items (47.7%). Analysis of variance (ANOVA) indicated significant differences in the total scores between groups for age, ethnicity, marital status, employment status, and cancer contact (Table 3). Older participants, participants of non-Arab ethnicity, and those who were married, employed, or had cancer contacts were found to have higher scores. The multiple regression analysis model that considered all the sociodemographic factors (apart from region) indicated that employment and cancer contact were significant predictors of overall knowledge scores (p<0.05).
Table 3.
Influence of sociodemographic factors on total knowledge scores for prompted signs and symptoms and risk factor items.
| Sociodemographic Characteristic | All participants | |||||
|---|---|---|---|---|---|---|
| Mean total score out of 32 | P-value | Multiple regression analysis | ||||
| Beta | P-value | 95% confidence interval | ||||
| Lower | Upper | |||||
| Age | ||||||
| <18 | 14.37 | 0.004* | 0.030 | 0.211 | -0.203 | 0.922 |
| 18-39 | 15.37 | |||||
| 40+ | 15.65 | |||||
| Gender | ||||||
| Male | 15.60 | 0.058 | –0.019 | 0.444 | -0.788 | 0.346 |
| Female | 15.16 | |||||
| Ethnicity | ||||||
| Arab | 15.34 | 0.017* | 0.032 | 0.173 | -0.327 | 1.81 |
| Other | 16.46 | |||||
| Language | ||||||
| Arabic | 15.25 | 0.102 | 0.026 | 0.261 | -0.825 | 3.04 |
| English | 16.89 | |||||
| Marital status | ||||||
| Single | 14.99 | 0.000* | 0.020 | 0.389 | -0.277 | 0.712 |
| Married | 15.71 | |||||
| Education | ||||||
| No qualifications | 15.00 | 0.184 | 0.004 | 0.856 | -0.407 | 0.490 |
| <University | 15.07 | |||||
| ≥University | 15.41 | |||||
| Other | 13.13 | |||||
| Employment status | ||||||
| Employed | 15.86 | 0.000* | –0.088 | 0.001* | -1.50 | -0.409 |
| Unemployed | 14.92 | |||||
| Cancer contact | ||||||
| Yes | 15.97 | 0.000* | –0.082 | 0.000* | -1.39 | -0.475 |
| No | 14.94 | |||||
P-values for ANOVA Welch and Brown-Forsythe.
represents significance p<0.05
The means of the overall knowledge scores for recognized items for personally delivered and online questionnaires were significantly different (14.5±4.97 in person, 15.9±5.44 online; ANOVA, p<0.001). To determine the effect of the questionnaire delivery method on the knowledge scores, univariate GLM models were used to adjust for differences in sociodemographic characteristics. The initial analysis showed interactions in the sociodemographic characteristics of education, gender, and marital status; thus, these items were excluded. The analysis for all participants indicated that differences observed in the overall knowledge scores between the 2 participant pools were due to the differences between the 2 sociodemographic compositions (method adjusted for age, ethnicity, language, employment status, cancer contact; means: 16.1±0.6 in person, 17.2±0.5 online; F=2.204, p=0.138).
Recognized items for barriers to seeking help
The data collected for all the participants indicated that the top 3 recognized items for barriers to seeking help were “Worry about what the doctor might find” (74.0%) and “Too scared” (67.6%; Table 4). The data for all the participants showed that those who were willing to see their doctors within a week scored significantly higher for their knowledge scores than those who did not think an action was ever required (mean knowledge score for those who declared taking action within a week: 15.4±5.3, N=2,038; mean knowledge score for those who declared taking action after a week: 15.4±5.0, n=598; mean knowledge scores for those who would not take action: 14.2±5.7, n=364; Brown-Forsythe ANOVA, p<0.005).
Table 4.
Participants’ agreement with statements associated with barriers to seeking help.
| Barriers to seeking help | All participants | |
|---|---|---|
| n | (%) | |
| Worried about what the doctor might find | 2220 | (74.0) |
| Too scared | 2029 | (67.6) |
| Difficult to make an appointment with the doctor | 1737 | (57.9) |
| Too busy to make time to go to the doctor | 1521 | (50.7) |
| Have too many other things to worry about | 1503 | (50.1) |
| Difficult to arrange transport to the doctor’s clinic | 1389 | (46.3) |
| Difficult to talk to the doctor | 1113 | (37.1) |
| Too embarrassed | 671 | (22.4) |
| Do not feel confident talking about my symptoms with the doctor | 618 | (20.6) |
| Worried about wasting the doctor’s time | 402 | (13.4) |
Discussion
Main findings of this study
This study showed low awareness of the signs and symptoms of CNSTs, as well as associated risk factors, among participants residing in the KSA. The data highlighted concerns associated with anticipated delays in seeking medical advice, including being scared and facing a diagnosis, and showed a relationship between the willingness to act and the level of CNST knowledge. In addition, this work showed that using 2 approaches to deliver a questionnaire - personal delivery and online access - could widen the composition of participants and provide an alternative for questionnaire distribution in areas where there is a lack of directories.
What is already known about this topic
An extensive search of the literature highlighted only 3 studies concerned specifically with CNST public awareness worldwide.3,25 Other published studies for cancer awareness in the KSA have focused on non-specified cancer awareness, breast cancer, colorectal cancer, and oral cancer.26-30 Comparable to the data from this study, the top recognized warning signs of brain tumors in the United Kingdom were vomiting and headaches.3 Recently, the frequencies of symptoms experienced by CNST patients were investigated.10 The most widespread symptoms were fatigue and feeling drowsy, while the least frequently experienced were nausea, vomiting, and dyspnea.
Unfortunately, no studies assessing the public perception of risk factors for CNST were found. Most studies addressed risk factors in the context of general cancer awareness.31-33 The top recognized cancer-associated risk factors include smoking, stress, low vegetable and high alcohol intake, lifestyle, and genetics. In the KSA, the top-ranked recognized cancer risk factors were tobacco, alcohol, and intake of fruit and vegetables.27
Knowledge of general cancer awareness has been previously shown to be influenced by employment or cancer contact.27,34 In addition, increased knowledge has previously been associated with a lower anticipated delay in requesting medical advice.35 However, many barriers for such action, including fear, are still highly reported in cancer awareness studies.34,36
What this study adds
This is the first study in the region to report on public awareness for CNSTs, and it is one of the few similar publications. Unlike those of many cancers, such as breast cancer or melanoma, the signs and symptoms of CNST can be vague, and lack of recognition could lead to a lower quality of life and possible fatality.3,9,10 The level of awareness for specific signs and symptoms associated with CNSTs, such as excessive emotional problems, enlarged head development, behavioral problems, personality change, unusual head tilt or stiff neck, or congenital anomaly of the brain, are not necessarily addressed in cancer awareness studies.27,34,35 Indeed, in this research, these vital signs were shown to be less frequently recognized. These data highlight the wide gap between the public perception of CNST-associated symptoms and their actual frequencies of occurrence. Thus, the work indicates a need for professional awareness programs to improve public awareness concerning the signs and symptoms associated with CNSTs.
The data presented here show that the personally modifiable risk factors, such as eating processed food, low intake of fruits and vegetables, exercising, and monitoring weight, were least recognized. In contrast, less-modifiable risk factors, such as exposure to radiation and pesticides, were more recognized. Collectively, and in contrast to what is perceived for cancer risks, an underlying belief that risks for CNSTs are mainly nonmodifiable may be present.
Compared with recent cancer awareness studies, the means of the total knowledge scores for CNST awareness reported in this study were low, with the participants receiving less than 50% of the total possible scores.27,34,36 The most recognized barriers out of all the recognized items were “Worry about what the doctor might find” and being “Too scared.” Participants who were willing to see their doctors within a week scored significantly higher for their knowledge than those who did not think an action was ever required. These outcomes indicate that, in addition to improving knowledge, cancer and CNST awareness campaigns could benefit from targeting fears, perhaps by emphasizing the advantages and benefits of early detection, underlining the presence of low-grade cancers that are associated with high recovery rates, and publicizing the improvements seen in current treatment outcomes. Perhaps a philosophy of “Better check it out” should be more effectively endorsed, as delays in seeing the doctor could allow for the progression of cancer aggressiveness.
The work presented here also showed that the frequencies for sociodemographic characteristics were significantly different for the 2 participant pools recruited using the different delivery methods. More participants that were under 18 years old, as well as those that were unemployed, were recruited online. Thus, the method of delivery appears to influence the sociodemographic composition of participants.
Limitations of this study
Some limitations were associated with the structure of the instrument. Many cancer awareness studies that have used CAM or based their instrumentation on CAM rely on recognition items to estimate the level of knowledge and awareness. However, variation in the significance between recall and recognition for individual items has been seen in previous studies, and different rankings of risk factor items for recall and recognition in the same population have previously been reported.31,37 Thus, it is difficult to determine which better captures the concept of cancer awareness. Another limitation of the instrument is related to risk factor items presented as associated with CNSTs. Many of these items are still being investigated at a global level, and they have several associated controversies. Excluded items, such as smoking and environmental pollution, have recently been investigated in relation to CNSTs.38-40
The limitations associated with the distribution methods included the inability to report the willingness to participate in the survey, and thus, being unable to record information for non-responders. This may have resulted in a bias toward participants who are naturally responsive. However, it is worth noting that some participants were reluctant to act following disease sign detection, suggesting the inclusion of some disinclined participants. Unfortunately, no national population database listing of households in the local government area was available; thus, the study design was limited to a nonprobability sampling technique. Consequently, this survey, like other cancer awareness investigations in the KSA, had an underlying partiality for including mainly young, educated females, raising concerns about the lack of involvement of males and the elderly.26-30,41 This lack of involvement could be a potential barrier for the improvement of cancer and CNST awareness for these groups. Thus, there is a need to create a national population database in the KSA that can be utilized for health-related studies.
Appendix 1
Participants’ responses to prompted question for signs and symptoms of CNS tumors.
| Signs and Symptoms | Method of Administration | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Personal | Online | |||||||||||
| Y | N | DK | Y | N | DK | |||||||
| n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | |
| Not eating or having a poor appetite | 908 | 60.5 | 329 | 21.9 | 252 | 16.8 | 766 | 51.1 | 428 | 28.5 | 306 | 20.4 |
| Experiencing abnormal involuntary movements | 1223 | 81.5 | 158 | 10.5 | 114 | 7.60 | 1315 | 87.7 | 84 | 5.60 | 101 | 6.73 |
| Difficulty in awareness and learning | 839 | 55.9 | 427 | 28.5 | 229 | 15.3 | 863 | 57.5 | 437 | 29.1 | 200 | 13.3 |
| Congenital anomaly of brain | 670 | 44.7 | 460 | 30.7 | 362 | 24.1 | 456 | 30.4 | 715 | 47.7 | 329 | 21.9 |
| Drowsiness or prolonged sleepiness | 857 | 57.1 | 357 | 23.8 | 275 | 18.3 | 843 | 56.2 | 393 | 26.2 | 264 | 17.6 |
| Think back pain, back stiffness, odd posture | 577 | 38.5 | 591 | 39.4 | 327 | 21.8 | 489 | 32.6 | 676 | 45.1 | 335 | 22.3 |
| Excessive emotional problems | 390 | 26.0 | 784 | 52.3 | 321 | 21.4 | 311 | 20.7 | 889 | 59.3 | 300 | 20.0 |
| Arm paralyzed, monoplegia, muscle weakness | 782 | 52.1 | 370 | 24.7 | 343 | 22.9 | 768 | 51.2 | 439 | 29.3 | 293 | 19.5 |
| Physical delay | 612 | 40.8 | 513 | 34.2 | 371 | 24.7 | 521 | 34.7 | 636 | 42.4 | 343 | 22.9 |
| Unusual head tilt or stiff neck | 686 | 45.7 | 438 | 29.2 | 372 | 24.8 | 755 | 50.3 | 435 | 29.0 | 310 | 20.7 |
| Clumsiness loss of balance | 1125 | 75.0 | 192 | 12.8 | 179 | 11.9 | 1261 | 84.1 | 127 | 8.47 | 112 | 7.47 |
| Deafness | 684 | 45.6 | 469 | 31.3 | 345 | 23.0 | 823 | 54.9 | 422 | 28.1 | 255 | 17.0 |
| Headaches | 1220 | 81.3 | 150 | 10.0 | 127 | 8.47 | 1335 | 89.0 | 79 | 5.27 | 86 | 5.73 |
| Visual impairment | 870 | 58.0 | 343 | 22.9 | 276 | 18.4 | 1054 | 70.3 | 281 | 18.7 | 165 | 11.0 |
| Enlarged head development | 727 | 48.5 | 349 | 23.3 | 416 | 27.7 | 708 | 47.2 | 459 | 30.6 | 333 | 22.2 |
| Loss of bladder/bowel control | 269 | 17.9 | 660 | 44.0 | 561 | 37.4 | 166 | 11.1 | 861 | 57.4 | 473 | 31.5 |
| Behaviour problems, personality change, constant confusion | 374 | 24.9 | 631 | 42.1 | 486 | 32.4 | 336 | 22.4 | 776 | 51.7 | 388 | 25.9 |
| Vomiting without diarrhoea | 512 | 34.1 | 487 | 32.5 | 496 | 33.1 | 574 | 38.3 | 572 | 38.1 | 354 | 23.6 |
| Loss of weight | 787 | 52.5 | 351 | 23.4 | 361 | 24.1 | 857 | 57.1 | 369 | 24.6 | 274 | 18.3 |
Y - yes, N - no, DK - do not know
Appendix 2
Participants’ responses to prompted possible risk factors for CNS tumors.
| Risk Factors | Method of administration | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Personal | Online N (%) | |||||||||||||||||||
| SA | A | NS | D | SD | SA | A | NS | D | SD | |||||||||||
| n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | |
| Radioactive location/occupation | 716 | 47.7 | 487 | 32.5 | 231 | 15.4 | 53 | 3.53 | 12 | 0.8 | 1003 | 66.9 | 318 | 21.2 | 157 | 10.5 | 8 | 0.53 | 10 | 0.67 |
| Frequent Exposure to Dental X-Rays | 220 | 14.7 | 441 | 29.4 | 634 | 42.3 | 169 | 11.3 | 29 | 1.93 | 275 | 18.3 | 358 | 23.9 | 632 | 42.1 | 85 | 5.67 | 127 | 8.47 |
| Exposure to CT Scans | 240 | 16.0 | 463 | 30.9 | 579 | 38.6 | 182 | 12.1 | 28 | 1.87 | 291 | 19.4 | 396 | 26.4 | 612 | 40.8 | 66 | 4.40 | 118 | 7.78 |
| Frequent Exposure BPA (Bisphenol A) | 379 | 25.3 | 569 | 37.9 | 417 | 27.8 | 114 | 7.60 | 20 | 1.33 | 531 | 35.4 | 477 | 31.8 | 395 | 26.3 | 30 | 2.00 | 56 | 3.73 |
| Exposure to Pesticides | 392 | 26.1 | 633 | 42.2 | 342 | 22.8 | 110 | 7.33 | 21 | 1.40 | 618 | 41.2 | 474 | 31.6 | 327 | 21.8 | 28 | 1.87 | 44 | 2.93 |
| Repetitive long period exposure to mobile phones | 351 | 23.4 | 592 | 39.5 | 404 | 26.9 | 121 | 8.07 | 30 | 2.00 | 584 | 38.9 | 449 | 29.9 | 352 | 23.5 | 37 | 2.47 | 60 | 4.00 |
| Low fruit and vegetable intake | 84 | 5.60 | 212 | 14.1 | 467 | 31.1 | 531 | 35.4 | 202 | 13.5 | 91 | 6.07 | 373 | 24.9 | 587 | 39.1 | 116 | 7.73 | 251 | 16.7 |
| Red/processed meat | 60 | 4.00 | 168 | 11.2 | 530 | 35.3 | 577 | 38.5 | 163 | 10.9 | 84 | 5.60 | 338 | 22.5 | 633 | 42.2 | 136 | 9.07 | 251 | 16.7 |
| Overweight (BMI over 25) | 102 | 6.80 | 227 | 15.1 | 535 | 35.7 | 516 | 34.4 | 112 | 7.47 | 199 | 13.3 | 410 | 27.3 | 545 | 36.3 | 113 | 7.53 | 201 | 13.4 |
| Over 70 years of age | 120 | 8.00 | 289 | 19.3 | 472 | 31.5 | 480 | 32.0 | 132 | 8.80 | 244 | 16.3 | 416 | 27.7 | 523 | 34.9 | 106 | 7.07 | 169 | 11.3 |
| Close relative with CNST | 214 | 14.3 | 363 | 24.2 | 326 | 21.7 | 411 | 27.4 | 182 | 12.1 | 389 | 25.9 | 488 | 32.5 | 314 | 20.9 | 87 | 5.80 | 159 | 10.6 |
| Infection | 67 | 4.47 | 113 | 7.53 | 283 | 18.9 | 556 | 37.1 | 474 | 31.6 | 91 | 6.07 | 309 | 20.6 | 413 | 27.5 | 134 | 8.93 | 321 | 21.4 |
| Low physical activity | 87 | 5.80 | 130 | 8.67 | 414 | 27.6 | 569 | 37.9 | 300 | 20.0 | 154 | 10.3 | 366 | 24.4 | 517 | 34.5 | 112 | 7.47 | 241 | 16.1 |
A - strongly agree, A - agree, NS - not sure, D - disagree, SD - strongly disagree, BMI - body mass index, CNST - central nervous system tumor
Appendix 3
Participants’ responses to statements associated with barriers to seeking help.
| Barriers to seeking help | Method of administration | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Personal | Online N (%) | |||||||||||
| Y | N | DK | Y | N | DK | |||||||
| n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | |
| Too embarrassed | 430 | 28.7 | 1034 | 68.9 | 33 | 2.20 | 241 | 16.1 | 1184 | 78.9 | 70 | 4.70 |
| Too scared | 960 | 64.0 | 510 | 34.0 | 28 | 1.90 | 1069 | 71.3 | 400 | 26.7 | 26 | 1.70 |
| Worried about wasting the doctor’s time | 233 | 15.5 | 1215 | 81.0 | 48 | 3.20 | 169 | 11.3 | 1277 | 85.1 | 45 | 3.00 |
| Difficult to talk to the doctor | 552 | 36.8 | 870 | 58.0 | 68 | 4.50 | 561 | 37.4 | 848 | 56.5 | 86 | 5.70 |
| Difficult to make an appointment with the doctor | 803 | 53.5 | 619 | 41.3 | 69 | 4.60 | 934 | 62.3 | 499 | 33.3 | 61 | 4.10 |
| Too busy to make time to go to the doctor | 775 | 51.7 | 650 | 43.3 | 68 | 4.50 | 746 | 49.7 | 678 | 45.2 | 67 | 4.50 |
| Have too many other things to worry about | 765 | 51.0 | 656 | 43.7 | 71 | 4.70 | 738 | 49.2 | 691 | 46.1 | 62 | 4.10 |
| Difficult to arrange transport to the doctor’s clinic | 651 | 43.4 | 765 | 51.0 | 79 | 5.30 | 738 | 49.2 | 692 | 46.1 | 68 | 4.50 |
| Worried about what the doctor might find | 1036 | 69.1 | 402 | 26.8 | 58 | 3.90 | 1184 | 78.9 | 269 | 17.9 | 42 | 2.80 |
| Do not feel confident talking about my symptom with the doctor | 532 | 35.5 | 878 | 58.5 | 87 | 5.80 | 86 | 5.70 | 122 | 8.10 | 1292 | 86.1 |
Y - yes, N - no, DK - do not know
Footnotes
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