Abstract
Prostate cancer is the leading male cancer in sub-Saharan Africa, with 74,878 (17.4%) new cases and 32,390 (11.6%) deaths in 2022. In Togo, the total number of prostate cancers was 726 in 2021. Screening methods are readily available in Togo. However, prostate cancer is still detected at a late stage. This study aimed to determine the factors associated with adherence to prostate cancer screening among retired men in Togo, 2023, using the Health Belief Model. A national descriptive and analytical exploratory cross-sectional study was carried out from March 1 to May 31, 2023. A total of 288 retirees were included. Overall, 54.9% of retirees perceived their vulnerability to prostate cancer, 54.9% perceived its severity, 52.4% perceived barriers to screening, 50.3% perceived benefits from screening, 53.1% perceived their self-efficacy for screening, and 55.2% perceived cues to action. A total of 83% of retirees agreed to undergo prostate cancer screening. The absence of a history of chronic pathology (adjust odds ratio [aOR] = 3.0, 95% CI [1.4, 6.2], p = .010), frequency of annual medical consultation (aOR = 0.3, 95% CI [0.1, 0.8], p = .020), perceived obstacles (aOR = 0.4, 95% CI [0.2, 0.9], p = .029) and perceived cues to action (aOR = 5.1, 95% CI [1.9, 15.1], p = .002) are significantly associated with adherence to prostate cancer screening. This study reported a high level of adherence to prostate cancer screening among retirees. It demonstrated that the absence of a history of chronic pathology, frequency of annual medical consultation, perceived barriers, and perceived incentive to action were significantly associated with adherence to prostate cancer screening.
Background
Prostate cancer (PCa) is a disease characterized by the uncontrolled proliferation of malignant cells in the prostate gland (Dessaigne, 2012). According to the World Health Organization (WHO), it will be the fourth most common cancer in the world in 2020, with 1.41 million cases (Organisation mondiale de la santé, 2022). In 2022, it was the second most common cancer in men, with 1,467,854 new cases and 397,430 deaths worldwide (Global Cancer Observatory, 2024). Prostate cancer is the leading male cancer in sub-Saharan Africa, with 74,878 (17.4%) new cases and 32,390 (11.6%) deaths in 2022 (World Health Organization, 2023). In 2013, the morbidity burden of PCa was 11% in Sudan, 36% in Senegal, 43% in South Africa, and 94% in Uganda (Jalloh et al., 2013). In Niger, the annual hospital incidence was 37 cases in 2022 (Halidou et al., 2022).
PCa has been increasing in Togo for almost 10 years. According to Amégbor et al. (2009), it was the most common cancer in men over 50 in Togo. From 1993 to 2012, 506 cases of PCa were collected at the pathology laboratory of the University Teaching Hospital of Tokoin (Darré et al., 2014). The total number of cases has increased from 499 in 2020 (Globocan, 2020) to 726 in 2021 throughout Togo (Ministère de la Santé, de l’Hygiène Publique et de l’Accès Universel aux Soins, 2023).
PCa generally has a good prognosis if detected early (Haute autorité de santé, 2013). PCa screening includes digital rectal examination (DRE) and prostate-specific antigen (PSA) testing (La Fondation ARC pour la recherche sur le cancer, 2022). Even if it is available, the treatment of PCa is costly; unlike when it is detected early and the treatment is less burdensome. Early detection is therefore a measure of preventing the disease (La Fondation ARC pour la recherche sur le cancer, 2022).
In Togo, the population is predominantly young; people under 15 account for around 42% of the total population; men aged 60 and over represent 4.3% (Institut National de la Statistique et des Etudes Economiques et Démographiques-Togo, 2023). In Togo, a retiree is someone who has reached the retirement age limit and stopped all paid work; the retirement age in the Togolese civil service is 60, but it varies according to the sector of activity (République Togolaise, 2008). This makes retired men an age group at risk for PCa. In Africa, retired people are considered elders, respected and listened to. Their physical, economic, and social suffering leads to the emotional and psychological suffering of those around them (Berthe et al., 2013). Screening methods (DRE and PSA testing) are readily available in Togo. However, PCa is still detected at a late stage through severe symptoms such as micturitional disorders (89.2%) and back pain (67.2%; Tengue et al., 2016).
The literature reports that adherence to PCa screening depends on several factors, including general practitioner’s perceptions, health determinants, and an individual’s perception of the disease (Ojewola et al., 2017; Yang et al., 2013). Indeed, a nationwide, population-based cross-sectional study performed by Akiyama et al. in Japan in 2023 reported that perceived cues to action increase the probability of adherence to PCa screening by two-fold (adjust odds ratio [aOR] = 1.9, 95% CI [1.2, 3.3]; Akiyama et al., 2023). The Health Belief Model (HBM) is a psychological model used to explain and predict health-related behavior. It explains the predisposing conditions for the use of health services such as screening. It suggests that people’s beliefs about health problems explain their engagement or not in the use of a health service. This model is therefore ideal for explaining the perception and adoption or not of PCa screening (Janz & Becker, 1984). However, few data are available on adherence to PCa screening in Togo. Having such data would enable us to understand the factors that determine the uptake of PCa screening among at-risk individuals, such as retirees. The aim of this study was to determine the factors associated with adherence to PCa screening among retired men in Togo in 2023 using the HBM.
Methods
Study Design and Period
A descriptive and analytical exploratory cross-sectional study was carried out from March 1 to May 31, 2023. The study was conducted in Togo, a West African country in the Gulf of Guinea, covering an area of 56,600 km2. In 2022, Togo’s population was estimated at 8,095,498, of whom 51.3% were women (Institut National de la Statistique et des Etudes Economiques et Démographiques-Togo, 2023). Togo’s human development index rose from 0.539 in 2021 to 0.547 in 2024, placing the country in first place in the UEMOA (West African Economic and Monetary Union). Gross National Income per person has risen from US $2,167 in 2021 to US $2,214 in 2024. Life expectancy at birth was 61.6 years in 2023 (Programme des Nations Unies pour le développement-Togo, 2024). The health care system is pyramidal, organized into three levels: primary, secondary, and tertiary. There are six health regions, 17,194 health workers, 2,152 healthcare facilities, and 286 pharmaceutical facilities in 2022 (Ministère de la santé et de l’hygiène publique, 2022).
Population, Inclusion Criteria, and Sample Size
All retired men residing in Togo in 2023 were eligible. Retired men who were at least 50 years old at the survey date, admitted to retirement, and who had given their consent were included. Retired men diagnosed with or cured of PCa and those with benign prostatic hypertrophy were not included. We chose this population because it is easily accessible and represents an interesting group on which we can act to reduce PCa in Togo. The number of retired men to be included was calculated using Cochran’s formula:
With N = sample size, z = score corresponding to the 95% confidence level, p = estimated prevalence of PCa in Togo, and m = the margin of error. For a national hospital prevalence of PCa estimated at 18.5% by Darré et al. in 2016 (Darre et al., 2017), a Z = 1.96, a margin of error of 5%, and assuming a non-respondent rate of 10%, a minimum of 255 retired men had to be included.
Sampling
All six health regions of Togo were included. We then carried out a four-stage sampling: the first stage was the health district, the second was the health commune, the third was the chief town of the health commune, and in the fourth stage, the retirees met in the chief towns of the health communes. In the first, second, and third stages, sampling with probability proportional to size was used to select half of the elements. In the fourth stage, once in the locality, a direction was randomly selected by turning a bottle on the ground, and the direction chosen was that of the end of the bottle. In this direction, consecutive sampling was used to include all retirees who met the inclusion criteria in households or public squares. Population estimates were derived from the 2010 Fourth General Population and Housing Census (République Togolaise, 2010).
Data Collection
Data were collected during face-to-face interviews by trained students from Togo’s national schools for paramedics. We used Çapık and Gözüm’s structured questionnaire designed in 2011 to assess the adherence to PCa screening according to the HBM in Turkey (Çapık & Gözüm, 2011). It is a questionnaire consisting of three parts: individual characteristics, medical history, and the HBM variables (Supplemental Appendix 3). The HBM variables (perceived susceptibility, perceived severity, perceived barriers, perceived benefits, perceived self-efficacy, and perceived cues to action) are five-modality ordinal qualitative with a Likert scale ranging from 1 to 5: 1—strongly disagree, 2—disagree, 3—indifferent, 4—agree, 5—strongly agree. They were then transformed into binary variables in relation to the median score: “No” if the score is less than the median and “Yes” if the score is greater than or equal to the median. The outcome of interest, adherence to PCa screening, was also transformed into a qualitative binary: 0 = No and 1 = Yes, depending on whether the score was above or equal to or below the median. The questionnaire was digitized and made available online using KoboToolbox software (Cambridge, MA, USA) for data collection.
Data Analysis
Completed questionnaires were checked for completeness and consistency. Data were then exported to SPSS Version 27.0 for analysis. Descriptive statistics were performed. Qualitative variables were presented as numbers and proportions. Quantitative variables were presented as medians with their interquartile range (IQR). The internal consistency of our questionnaire was determined using Cronbach’s alpha coefficient. Univariate logistic regression was first performed. Variables with a p value less than 0.20 were then entered into a multivariable logistic regression model to determine factors associated with adherence to PCa screening. In the latter model, variables were considered significant if the p value was less than or equal to 0.05.
Ethical and Deontological Aspects
This study was approved by the Comité de Bioéthique pour la Recherche en Santé du Togo (Notice No. 033/2023/CBRS of June 22, 2023) and by the secretariat of the Ministère de la Santé, de l'Hygiène Publique et de l’Accès Universelle aux Soins (N° 111/2023/MSHPAUS/CAB/SG). The confidentiality of all information collected was maintained. The anonymity of respondents was protected by coding their identities.
Results
Individual Characteristics of Retirees in Togo
A total of 288 retirees with a median age of 63 years (IQR: 59–69) were included. The 60 to 79 age group was predominant (66.8%). Retirees were married in 92.6% of cases. The most common occupations were civil servants (25%) and teachers (20.1%). They were in the civil service sector (48.3%), had a secondary education (47.6%), and had health insurance (52.1%). Overall, 58.7% earned at least the guaranteed interprofessional minimum wage (GIMW) per month (52,000 FCFA or 80€). They were suffering from a chronic pathology in 56.9% of cases. A total of 35.4% of retirees had not consulted a doctor in the year before the study. In 82.6% and 81.6% of cases, respectively, the retirees had never been screened for PCa by DRE or PSA testing. They had a family history of PCa in 87% of cases (Table 1).
Sociodemographic Characteristics of Retirees in Togo (N = 288)
Note. IQR = interquartile range; PSA = prostatic specific antigen; DRE = digital rectal examination; PCa = prostate cancer; GIMW = guaranteed interprofessional minimum wage; GIMW in Togo = 52,000 FCFA or 80€.
Architect, surveyor, housekeeper, breeder, docker, security guard, chef, motorcycle cab driver, radio technician, pump attendant, agronomist, fireman, engineers, finance banking, secretary….
Bricklayer, scrap metal worker, carpenter, mechanic, plumber, electrician/electronician, shoemaker, driver, hairdresser.
HBM Variables Description
The median scores obtained were 17 (IQR: 15–20) for perceived susceptibility, 20 (IQR: 18–23) for perceived severity, 18 (IQR: 15–20) for perceived obstacles, 21 (IQR: 19–24) for perceived benefits, 26 (IQR: 23–29) for perceived self-efficacy, and 14 (IQR: 12–16) for perceived cues to action. The items in our questionnaire had acceptable internal consistency: perceived susceptibility (Cronbach’s α = .75), perceived severity (Cronbach’s α = .75), perceived obstacles (Cronbach’s α = .61), perceived benefits (Cronbach’s α = .88), perceived self-efficacy (Cronbach’s α = .80) and perceived cues to action (Cronbach’s α = .71; Table 1 in Supplemental File). Retirees’ perceptions of PCa were 54.9%, 54.9%, 52.4%, 50.3%, 53.1%, and 55.2%, respectively, for susceptibility, severity, obstacles, benefits, self-efficacy, and cues to action. A total of 83% of retirees agreed to be screened for PCa (Table 2).
HBM Variables Description (N = 288)
Note. Yes if score greater than or equal to Median; No if score less than Median. PCa = prostate cancer.
Relationship Between Adherence to PCa Screening and Individual Characteristics in Retirees
Bivariate analysis using Pearson’s Chi-square test at the 5% significance level shows that type of retiree (p = .040), health insurance coverage (p = .000), monthly income (p = .020), history of chronic pathology (p = .030), and annual medical consultation (p = .000) are significantly associated with adherence to PCa screening. Measuring the V of Cramer showed that the association between adherence to screening and sociodemographic characteristics was weak for the type of retiree (V = 0.17), monthly income (V = 0.18), and history of chronic disease (V = 0.12), and moderate for the availability of health insurance (V = 0.23) and annual frequency of medical consultations (V = 0.25; Table 2 in Supplemental File).
Relationship Between Adherence to PCa Screening and HBM Variables in Retirees
In bivariate analysis using Pearson’s Chi-square test at the 5% significance level, perceived susceptibility (p = .010), perceived obstacles (p = .000), perceived benefits (p = .000), perceived self-efficacy (p = .000) and perceived cues to action (p = .000) were significantly associated with adherence to PCa screening. Measuring the V of Cramer showed that the links were weak for perceived susceptibility (V = 0.150) and perceived obstacles (V = 0.17) and moderate for perceived benefits (V = 0.27), perceived self-efficacy (V = 0.28) and perceived cues to action (V = 0.32; Table 3).
Relationship Between Adherence to PCa Screening and HBM Variables
Pearson’s Chi-square test significance.
Factors Associated With PCa Screening Adherence in Retirees
The absence of a history of chronic pathology, frequency of annual medical consultation, perceived obstacles, and perceived cues to action are significantly associated with PCa screening adherence. Indeed, the absence of a history of chronic pathology increases the probability of adherence to PCa screening by three times (aOR = 3.0, 95% CI [1.4, 6.2], p = .010). Retirees who never consult a doctor (aOR = 0.3, 95% CI [0.1, 0.8], p = .020) and those who rarely consult a doctor in the year (aOR = 0.3, 95% CI [0.1, 0.9], p = .050) have a 70% lower chance of adhering to PCa screening. Perceived obstacles are associated with a 60% lower chance (aOR = 0.4, 95% CI [0.2, 0.9], p = .029) of adhering to PCa screening. Retirees who perceived cues to action were 5.1 times more likely to adhere to screening (aOR = 5.1, 95% CI [1.9, 15.1], p = .002; Table 4).
Factors Associated With PCa Screening Adherence in Retirees
Note. PCa = prostate cancer; GIMW = guaranteed interprofessional minimum wage; GIMW in Togo = 52,000 FCFA or 80€; OR = odds ratio; aOR = adjust odds ratio; 95% CI = 95 percent confidence interval; Ref = reference.
Univariate logistic regression significance.
Multivariate logistic regression significance.
Discussion
This study aimed to determine the factors associated with adherence to PCa screening among retirees in Togo in 2023, using the HBM. A total of 288 retirees were included. Overall, 54.9% of retirees perceived their vulnerability to PCa, 54.9% perceived its severity, 52.4% perceived barriers to screening, 50.3% perceived benefits from screening, 53.1% perceived their self-efficacy for screening, and 55.2% perceived cues to action. A total of 83% of retirees agreed to undergo PCa screening. The absence of a history of chronic pathology, frequency of annual medical consultation, perceived obstacles, and perceived cues to action are significantly associated with adherence to PCa screening.
HBM Variables
Perceived Susceptibility of PCa Among Retirees
In our study, 54.9% of retirees perceived their susceptibility to develop PCa. Our result is well above those reported by two cross-sectional studies carried out in Burkina Faso among retired men in Ouagadougou in 2020 (37.4%; Sawadogo, 2020) and in Kenya among civil service health professionals in Kisumu County (15%; Opondo et al., 2022). This finding may reflect the impact of Togo’s national cancer plan, which has promoted early detection and community awareness since 2015 (Programme national de lutte contre le cancer, 2015).
Perceived Severity of PCa Among Retirees
Our study reports a perceived severity of 54.9%. This result is low compared with that reported in Burkina Faso, that is, 65.32% (Sawadogo, 2020). Another high result was reported in 2018 among adult men consulting outpatient services at Nairobi’s Mathare North Health Center (99%; Wachira et al., 2018). The lower perceived severity in our findings may be attributed to the population-based nature of our study in contrast to others conducted in hospital settings, where patients are more likely to have heard of the disease and, therefore, perceive its severity.
Perceived Barriers to PCa Screening Among Retirees
In our study, more than half of the retirees (52.4%) perceived barriers to PCa screening. A low level of perceived barriers was reported in a cross-sectional study of men aged 40 and over in Ekiti State, Nigeria, in 2020, at 34.4% (Ojewola et al., 2017). This level was also low in Burkina Faso in 2020, where only 24.7% of retirees perceived barriers (Sawadogo, 2020). The high perceived barriers in our study are probably explained by the low monthly income and the cost of care, which are barriers to the use of health services, thus explaining the scarcity of annual medical consultations observed in our study.
Perceived Benefits to PCa Screening Among Retirees
Only 50.4% of retirees perceived benefits from PCa screening. Our result is lower than that reported in a mixed cross-sectional study of adult men in the city of Kampala in Uganda in 2012, that is, 71% (Nakandi et al., 2013). A high proportion (95.12%) of perceived benefits was also reported among Burkinabe retirees in 2020 (Sawadogo, 2020). These higher levels of perceived barriers could be explained by their urban and hospital character: urban subjects are better informed about the benefits of PCa screening (Glanz et al., 2008).
Perceived Self-Efficacy to PCa Screening Among Retirees
Our study reported that 53.1% of retirees perceived their self-efficacy for PCa screening. A similar result was reported by Qin et al. (2022) in a primary analysis using data collected from African-American men in northeastern Ohio and the southeastern United States in 2019 at 54.3%. However, our result is well below the 80% reported in the United States (Dewitt Moore, 2002). This difference can be explained by the fact that the latter study was carried out among U.S. Army men with a good level of education.
Perceived Cues to Action for PCa Screening Among Retirees
Fifty-five-point two percent of retirees (55.2%) perceived cues to screen for PCa. In contrast, the level of cues to screen was low (30.7%) in a cross-sectional study carried out by Miller et al. (2020) in 2019 among African-American men in the states of Georgia, North Carolina, and Ohio. The lower perceived cues to action reported in the United States could be explained by the young age (35–44) of the participants in this study. Indeed, the literature reports that younger males underestimate their vulnerability to PCa and perceive fewer screening cues (Miller, 2014). Cues to PCa screening are often fear of cancer, quality of care, family history, and support by family and friends (Miller et al., 2020).
Factors Associated With Adherence to PCa Screening
History of Chronic Pathology and Likelihood of Adherence to PCa Screening
The absence of a history of chronic pathology significantly increased the odds of adherence to PCa screening by 3 (aOR = 3, 95% CI [1.4, 6.2], p = .010). Few studies have examined the relationship between medical history and the likelihood of adherence to PCa screening. However, it is known that patients with no chronic pathology are more motivated to maintain their good health. Indeed, a 2014 cross-sectional study of Jordanian men attending public health centers in the cities of Amman, Irbid, and Zarqa demonstrated that the existence of health motivation significantly increased the probability of adhering to PCa screening by 1.1 times (aOR = 1.1, 95% CI [1.0, 1.2], p = .030; Abuadas et al., 2015).
Annual Medical Consultation and Likelihood of Adherence to PCa Screening
In our study, never consulting (aOR = 0.3, 95% CI [0.1, 0.8], p = .020) or rarely consulting (aOR = 0.3, 95% CI [0.1, 0.9], p = .050) a doctor in the year reduced the probability of adhering to PCa screening by 70%. A similar association was reported by Gebru et al. (2023) in a cross-sectional study of outpatients treated at the Tikur Anbessa Specialized Hospital in Ethiopia: those who saw a doctor regularly (once every 6 months) were 4.3 times more likely to adhere to PCa screening (aOR = 4.3, 95% CI [2.5, 6.1], p < .001). In the United States, it has also been shown that the likelihood of having PCa screening was 2.7 times higher among people who regularly seek care (aOR = 2.7, 95% CI [1.9, 3.9], p < .001; Yang et al., 2013).
Perceived Barriers and Likelihood of Adherence to PCa Screening
Our results showed that perceived barriers reduced the likelihood of adherence to PCa screening by 60% (aOR = 0.4, 95% CI [0.2, 0.9], p = .029). The same association was reported in 2014 among Jordanian men, in whom the perception of barriers significantly decreased the probability of adherence to PCa screening by 13% (aOR = 0.8, 95% CI [0.8, 0.9], p < .010; Abuadas et al., 2015). Indeed, the literature reports that insufficient physician recommendation (63%), lack of information (51.1%) and screening centers (34.4%), low perception of susceptibility (32.8%), and financial constraints (5.9%) are barriers to PCa screening (Ojewola et al., 2017).
Screening Cues and Likelihood of Adherence to PCa Screening
Retirees who perceived cues are 5.1 times more willing to adhere to PCa screening (aOR = 5.1, 95% CI [1.9, 15.1], p = .002). The same association was reported in a Japanese population-based study, where the perception of cues to action increased the probability of adherence to PCa screening by two times (aOR = 1.9, 95% CI [1.2, 3.3], p < .000; Akiyama et al., 2023). The literature reports that a person’s likelihood of having heard about PCa and therefore of screening is significantly increased 11-fold (aOR = 10.8, 95% CI [6.7, 15], p < .001), 10-fold (aOR = 10.4, 95% CI [5.8, 14.9], p < .001) and 9.5-fold (aOR = 9.5, 95% CI [5.3, 13.7], p < .001) when the source of prompting for action came from caregivers, friends, and the media respectively (Oliver et al., 2011).
Originality of Our Study
Our study is the first that investigate factors associated with adherence to PCa screening among retired people in Togo. It is an exploratory study that targeted the entire Togolese national territory. We targeted a population at risk of PCa that is sometimes ignored in research projects. The study was carried out on a population basis rather than in a hospital setting; data were collected by trained native interviewers, a precaution that minimized selection and information bias. We ran a regression model, adjusting for the individual characteristics of the retirees (sociodemographic, economic, medical history, lifestyle, and practice of PCa screening). This model has the particularity of identifying the main factors affecting adherence to PCa screening.
Limitations of Our Study
The results of this study should be interpreted in light of its limitations. First, we carried out an exploratory study, the results cannot be generalized to the general population of retired men in Togo. However, this study provides initial information to guide future nationally representative studies.
We carried out a four-stage random sampling, ideally stratified by region of residence and field of activity. However, a database listing all pensioners in Togo, with up-to-date addresses and no omissions or duplications, so that they can be unambiguously identified and distributed throughout the country, does not exist in Togo and is difficult to implement. We believe that the survey we chose in view of this situation is appropriate and that it was carried out throughout Togo and included the majority of retired people from the various socio-professional strata of Togo.
Conclusion
This study reported a high level of adherence to PCa screening among retirees. It demonstrated that the absence of a history of chronic pathology, frequency of annual medical consultation, perceived barriers, and perceived incentive to action were significantly associated with adherence to PCa screening. This is a preliminary study, which could lead to further studies with robust designs and larger sample sizes. It highlights the importance of implementing actions to reduce perceived barriers by subsidizing the cost of PSA testing and actions to increase cues to action, such as incorporating targeted awareness campaigns into routine healthcare services.
Supplemental Material
sj-pdf-1-jmh-10.1177_15579883251344558 – Supplemental material for Factors Associated With Prostate Cancer Screening Adherence Among Retired Men in Togo, 2023
Supplemental material, sj-pdf-1-jmh-10.1177_15579883251344558 for Factors Associated With Prostate Cancer Screening Adherence Among Retired Men in Togo, 2023 by Diguibe Tien-Bale Bamide, Latame Komla Adoli, Sêdégnon Benoît Agossoukpe, Roméo Mèdéssè Togan, Hermine Tognon, Ismaël Simpore and Dieudonné Soubeiga in American Journal of Men's Health
Footnotes
Acknowledgements
Authors would like to thank the African Center for Research in Epidemiology and Public Health (CARESP) and Togo’s national schools for medical assistance.
Ethical Considerations
This study was approved by Togo’s Bioethics Committee for Health Research (notice n° 033/2023/CBRS du 22 Juin 2023) and by the Secretariat of the Ministry of Health, Public Hygiene and Universal Access to Health Care (notice n° 111/2023/MSHPAUS/CAB/SG). All patient information was anonymized and verbal consent was obtained from participants before data collection.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The research received financial support from the African Center for Research in Epidemiology and Public Health (CARESP) for data collection.
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.
Data Availability Statement
Data sets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Supplemental Material
Supplemental material for this article is available online.
References
Supplementary Material
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