Abstract
Objectives
Cancer education has been promoted under the Basic Plan for Cancer Education in Japan. We conducted a repeated cross-sectional survey of Japanese students to determine changes in attitudes regarding cancer over time.
Methods
A nationwide survey of fifth-grade elementary students was conducted in February 2013. A repeated cross-sectional survey was conducted following previous studies with second-year high school students in February 2019, as second-year high school students in 2019 corresponded to the generation of fifth-grade students in 2013. The self-administered, multiple-choice questionnaire inquired about the awareness of cancer and its causes and sources of cancer information. Statistical analyses were performed by calculating the percentage of selections and 95% confidence intervals for each question.
Results
The differences between values in 2019 and 2013 were examined. Responses were received from 94 schools (44.1%) in 2013 and 114 schools (52.8%) in 2019. After excluding incomplete responses, valid responses from 2213 and 3822 respondents, respectively, were analyzed. Desirable changes over time were observed in awareness. Increasing age was associated with a rise in misperceptions and a decline in desirable rather than undesirable perceptions of the causes of cancer. The Internet was a common source of information among high school students, followed by health education at school.
Conclusion
Cancer education in schools should aim to counteract misconceptions and promote positive, evidence-based information. Improving perceptions of cancer screening could increase intentions of undergoing screening. Additionally, presenting cancer information using social networking sites could help promote cancer prevention among junior high and high school students.
Introduction
Cancer has been the leading cause of death among Japanese people since 1981. In Japan, the age-adjusted mortality rate is declining, whereas the incidence rate is rising. Furthermore, an estimated 9,80,856 new cases of cancer were diagnosed in 2018. In addition, 3,76,425 people died of cancer in 20191-3
Moreover, studies examining the incidence of cancer among Japanese adolescents and young adults have reported nearly 20,000 new cases of cancer, as well as cancer types by age.4,5 Among the issues identified that require attention for the treatment of cancer in adolescents and young adults are inadequate support systems, with studies reporting the need for various types of support.6-9
There are reports of improved social functioning with appropriate follow-up.7,8 Studies examining the incidence of cancer in children, adolescents, and young adults have identified ways to increase public awareness of this issue. 9 In addition, the percentage of children correctly identifying cancer information has increased over the past decade. 10
Cancer education is promoted under the Basic Plan for Cancer Education in Japan. In Japanese schools, cancer education has been implemented since 2019. In 2017, it was clearly stated that “cancer shall also be covered” in the health and physical education section of the junior high school curriculum guidelines. This information was also included in the curriculum guidelines for high schools in 2018. Specifically, junior high school curriculum included the concept and causes of cancer, and high school curriculum included the need for social measures such as the importance of coexistence, spread of cancer screening, and dissemination of correct information, as well as the types and causes of cancer and treatment methods.
Studies have reported on students’ cancer awareness, 11 sources of information, 12 understanding, 13 and intention to receive screening, 14 as well as the potential of cancer education.15,16 Knowledge about cancer influences the intention to undergo cancer screening. 14 Therefore, in this study, we examined differences in cancer knowledge by age and evaluated whether the level of knowledge is associated with positive attitudes toward cancer. 16
The results of previous studies are useful for promoting cancer education. Providing children with accurate knowledge through cancer education is particularly necessary for their health.17-26
We conducted a survey of students across Japan in 2013.11-13 The findings of this research were considered when developing and implementing cancer education curricula. As this was a cross-sectional survey, we now attempted to expand our findings by conducting a repeated cross-sectional survey to determine changes in attitudes regarding cancer over time.
The purpose of this study was to clarify natural changes in attitudes regarding cancer over time by comparing data from elementary school students in 2013 and high school students in 2019. We believe that the findings can serve as baseline data for future studies to determine changes resulting from interventions.
Materials and Methods
A nationwide survey of fifth-grade elementary students was conducted in February 2013. A repeated cross-sectional survey was conducted with second-year high school students in February 2019. Second-year high school students (aged 16 years or older) in 2019 corresponded to the generation of fifth grade students (aged 10 or 11 years) in 2013.
Target schools were selected by checking the number of elementary and high school students at the time of each survey using the National School Directory. The ratio of students by county was calculated based on the county with the lowest number of students. This ratio was used to determine the number of schools to be sampled, and random sampling was used to select schools to be surveyed. The prefecture with the lowest student population was set to 1 school, and that with the highest student population was set to 18 for elementary schools and 19 high schools based on the ratio of the students. Currently, the maximum number of students in a Japanese school class is 40. However, the actual number of students often varies widely. In this study, we estimated the number of students per school to be about 30, the school response rate to be about 40%, and set the target sample size at about 2500.
The questionnaire items used for the survey were based on previous studies.11,12 The self-administered, multiple-choice questionnaire inquired about awareness of cancer, causes of cancer, and sources of cancer information.
The items were as follows: What are your impressions of cancer? Do you think cancer can be cured with treatment? Do you think cancer can be prevented? Do you think you will get cancer in the future? Will you be undergoing cancer screening tests when you are old enough to do so? Where do you think you can get a cancer screening? (Multiple answer); Who do you think should take part in cancer screening? (Multiple answer); What you think was/were the causes of cancer? Select multiple answers from 14 items (Tabaco, Alcohol, Heredity, Stress, Lack of exercise, Excessive fat intake, Excessive direct sunlight, Burnt fish or meat, Excessive salt intake, Bacteria/virus, Overweight, Food additives, Not eating vegetables, Endocrine disruptor); What are your sources of information about cancer? Select multiple answers from 10 items (TV, Health education at school, Internet, Hospital posters and advertisements, Family conversations, Newspapers, Others excluding family members or relatives, Comic books, Magazines, Other education at school). The questionnaire items were reviewed by several university faculty members specializing in health education and other experts, including physician, elementary school teacher, health and physical education teacher, school nurse teachers, and school board supervisor.
The survey was administered by teachers at the target schools. Students were informed verbally and in writing that the survey was anonymous, that it was not related to school performance, and that they were free to participate or withdraw from the survey. Respondents submitted their completed survey forms in personal envelopes. The survey supervisor returned the envelops with collected response forms in one package to protect privacy. Because the average response time in the preliminary survey was around 10 min, we asked the implementers to complete the survey in that time.
Statistical analysis was performed by calculating the percentage of selections and 95% confidence intervals for each question. The difference between the selection percentages in 2019 and 2013 was also calculated.
A logistic regression model was used to calculate the multivariable adjusted odds ratio (OR) for the association between cancer awareness and survey years. The 2013 group was used as a reference. The multivariable model included gender, having close relatives with cancer and each Variable (Cancer is scary, Cancer can be cured with treatment, Get cancer in the future, Cancer is preventable, Undergo cancer screening in the future). Multivariable-adjusted OR and 95 % confidence intervals (CI) were also calculated. IBM SPSS Statistics Desktop Version 26.0 for Windows was used for data compilation and statistical analysis. Listwise case deletion was implemented for questionnaires with missing data.
The reporting of this study conforms to STROBE guidelines. 27
Ethical Considerations
The study was approved by the Ethics Committee of Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-city, Niigata, JAPAN (approval numbers: 17382-130117, 21st January 2013; 18109-190116, 16th January 2019). Students were informed that their answers would remain anonymous and that they were free to refuse participation in the study without any penalty. Students were given the questionnaire and an envelope and were allowed to return blank questionnaires if they so wished. Consent for participation in the study was indicated by returning the completed questionnaires for collection by the schools. All questionnaires were filled anonymously.
Results
Responses were received from 94 schools (44.1%) in 2013 and 114 schools (52.8%) in 2019 (Figure 1). After excluding incomplete responses, valid responses from 2213 and 3822 respondents, respectively, were analyzed. Data collection.
Differences in Cancer Awareness Between 2013 and 2019.
Regarding the “Places where I think I can get screened for cancer,” 96.7% of participants in both surveys answered hospitals, 11.4% and 17.9% answered workplaces, and 41.4% and 31.2% answered local and public health centers. In response to the question, “Who do you think should be screened for cancer?” 38.0% and 61.6% of the participants responded that healthy people should get screened, 77.9% and 75.0% indicated that those with subjective symptoms should get screened, and 74.4% and 65.7% stated that those who are advised by their doctors to take the test should be screened.
In terms of perceived causes of cancer, tobacco (97.5% and 92.8%) was the most common answer, followed by alcohol (83.4 and 78.9%) (Figure 2). The percentages were higher in 2019 compared to 2013 for heredity (38.2% vs 71.7%), lack of exercise (33.1% vs 39.1%), and excessive exposure to direct sunlight (30.6% vs 37.9%). The percentages were higher in 2013 compared to 2019 stress (59.1% vs 52.1%), excessive fat intake (55.6% vs 38.6%), excessive salt intake (48.5% vs 34.8%), bacteria/viruses (60.2% vs 34.5%), Overweight (43.7% vs 31.0%), not eating vegetables (38.1% vs 27.9%), and environmental hormones (36.2% vs26.0%). Differences in cause recognition between 2013 and 2019.
Association Between Cancer Awareness and Survey Year.
aOdds ratio (2013 group used as a reference).
bConfidence interval.
cAdjusted for gender, having close relatives with cancer and each Variable (Cancer is scary, Cancer can be cured with treatment, Get cancer in the future, Cancer is preventable, Undergo cancer screening in the future).
Regarding cancer information sources, TV (96.3% vs 96.9%) was the most frequent answer (Figure 3). Percentages were lower in 2013 than in 2019 for learning from health lessons at school (20.2% vs 58.7%) and the Internet (27.6% vs 51.8%). Percentages were higher in 2013 than in 2019 for posters and flyers in hospitals (54.0% vs 30.0%), family conversations (47.4% vs 25.7%), newspapers (43.8% vs 20.3%), and magazines (14.3% vs 9.5%). Differences in Sources of information between 2013 and 2019.
Discussion
In this study, we conducted follow-up cross-sectional surveys of elementary school students in 2013 and high school students in 2019 to examine their attitudes toward, perceived causes of, and sources of information regarding cancer.
Changes in Awareness
The ratio of respondents who replied that “cancer is scary” decreased slightly in 2019 compared with 2013. 11 The proportion of participants who answered that cancer be cured with treatment decreased in 2019 (from 25.8% to 21.0%, Adjusted OR 0.81, P = 0.001). Conversely, the proportion of participants who responded that the causes of cancer are unknown increased in 2019 (from 48.1% to 62.3%). This increase could have been influenced by learning about different cancer types and survival rates. This increase could have been influenced by learning about a cancer has many things which do not understand a cause.28,29
Conversely, the proportion of participants who thought they will get cancer in the future increased in 2019 (from 8.5% to 24.2%, Adjusted OR 3.04, P < 0.001). The participants learned that one of out of two people in Japan suffers from cancer” during health education and from television commercials, and this likely influenced their knowledge about the incidence of cancer.27,28 Moreover, the proportion of participants who answered that cancer can be prevented decreased in 2019 (from 57.4% to 42.3%, Adjusted OR 0.59, P < 0.001). Certain gaps in learning while undergoing health education may have brought about this understanding.28,29
The proportion of participants who stated that they will undergo cancer screening decreased slightly in 2019 (from 77.9% to 71.0%, Adjusted OR 0.69, P < 0.001). This was likely because of health education, which affected the drop in cancer screenings due to burdens and costs.28,29
The results indicate that with increasing age, respondents’ attitudes toward cancer became more negative. Cancer education in schools, which is being promoted in Japan, should be based on scientific evidence and communicated in a positive manner to counteract this.
Moreover, the proportion of participants who responded that healthy people should receive cancer screening increased in 2019 (from 38.0% to 61.6%). This was likely owing to education on the importance of regular cancer screenings for early detection. A previous study reported that the recognition that healthy people should receive cancer screening was related to intention to undergo cancer screening in the future. 14 A desirable change was observed over time, and intention to undergo cancer screening through raising awareness improved. 14
Cause Recognition
Our results were in line with a study on college students in the US, which found that more than 90% of students understood the relationship between lung cancer and smoking. 30 The proportion of participants who reported heredity as the cause of cancer significantly increased in 2019. This finding was similar to that of previous study in which a high percentage of UK students believed that having a relative with cancer was one of the causes of breast or cervical cancer. 31
Conversely, fewer participants identified factors such as obesity, excessive salt consumption, not eating vegetables, bacteria and viruses, and excessive fat, despite evidence indicating that these factors were among the causes of cancer in Japan.32,33
Content on the prevention of infections, such as HPV and Helicobacter pylori, should be improved in cancer education, as awareness of the role of infection is low.34-36 In addition, a previous study on young men in Italy found that 26.1% of participants did not have sufficient knowledge of the risk factors of cancer. 37 Junior and senior high school education should include information on the causes of cancer and cancer prevention.
Sources of Information
The proportion of participants that highlighted health education at school as a source of cancer-related information increased in 2019. This was likely due to the promotion of health education in junior high schools and high schools.28,29 Similar results were reported in previous cross-sectional survey. 12 However, no relationship was found between school health education and cancer screening intention. 14 Education should include relevant factors associated with cancer screening intention.
More participants reported the Internet as a source of information in 2019 than in 2013. This was likely because Internet use has become even more widespread in society, including at school. A previous study found that sources of information were related to cancer screening intention. 14 However, previous studies examining the relationship between information sources and intention to undergo cancer screening showed no relationship with the Internet. 38
Television was the most common source of information in both 2013 and 2019. This was likely because many children appear on TV, and there are many opportunities to routinely receive cancer information. 38
Television improved the health literacy of students and provided a variety of cancer information. The content of sources of information that young people access should be chosen carefully. A recent study reported that social networking services (SNS) can become a source of cancer information.39-42
Developing sources of cancer information, including health education, SNS, and television, for junior high and high school students could aid in cancer prevention.
Limitations
This study has several limitations. We showed the number of participating schools and responses; however, students’ response rates were unknown. Therefore, future study should report the number of individuals targeted and response rates. Furthermore, both surveys had limited response rates of less than 70% and future studies should consider bias-controlled awareness level by taking the non-response rate into consideration.
In addition, it may be impossible to directly discuss the potential reason such as improvement of school education, independent learning, and change in school education policy during the period. Future research should consider using multivariate analyses that would take these factors into account.
Conclusion
Education about cancer in schools should aim to counteract misconceptions and promote positive, evidence-based information. In particular, improving student perceptions of cancer screening could increase intentions to undergo screening in the future. Furthermore, developing sources of cancer information could help promote cancer prevention.
Footnotes
Acknowledgments
We thank the participants and school officials in this survey.
Authors’ Contributions
Tsuyoshi Yokoshima and Koshu Sugisaki conceived the idea. Tsuyoshi Yokoshima and Koshu Sugisaki conducted the study. Tsuyoshi Yokoshima and Koshu Sugisaki analyzed the data. Tsuyoshi Yokoshima and Koshu Sugisaki wrote the manuscript. All authors reviewed and edited the manuscript.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by JSPS KAKENHI, grant number JP18H00998 and JP22H00994
Correction (October 2025):
Article updated; for further details please see the
Ethical Statement
Article Note
The following changes have been made to the article:
• In Table 2, the “Unadjusted” 95% Cl value for “Cancer is preventable” has been corrected from “.61-.78” to “.49-.60”.
• Few minor style corrections have been made under the “Discussion” section since its original publication.
• The “Limitations” heading has been added under the “Discussion” section.
