Acceptability of and willingness to pay for using a smartphone-based vaccination application in a Vietnamese cohort

Bach Xuan Tran,1,2 Quang N Nguyen,3,4 Anh Kim Dang,5 Giang Thu Vu,4 Vuong Quan Hoang,6 Phuong Viet La,7 Duc Anh Hoang,8 Nhue Van Dam,9 Thu Trang Vuong,10 Long Hoang Nguyen,11 Huong Thi Le,1 Carl A Latkin,2 Cyrus SH Ho,12 Roger CM Ho11,13 1Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam; 2Department of Health, Behavior and Society, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA; 3Université Claude Bernard Lyon 1, Villeurbanne 69100, France; 4Center of Excellence in Evidence-based Medicine, Nguyen Tat Thanh University, Ho Chi Minh City 700000, Vietnam; 5Institute for Global Health Innovations, Duy Tan University, Da Nang 550000, Vietnam; 6Centre for Interdisciplinary Social Research, Thanh Tay University, Hanoi, Vietnam; 7Vuong & Associates, Hanoi, Vietnam; 8Gateway International School, Hanoi, Vietnam; 9Faculty of Graduate Studies, National Economics University, Hanoi, Vietnam; 10Sciences Po Paris, Campus de Dijon, Dijon, France; 11Center of Excellence in Behavioral Medicine, Nguyen Tat Thanh University, Ho Chi Minh City 700000, Vietnam; 12Department of Psychological Medicine, National University Hospital, Singapore 119074, Singapore; 13Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119074, Singapore Background: The increasing accessibility of smartphone in Vietnam shows potential in using smartphone applications for vaccination management to improve compliance. However, the acceptability and financial feasibility of using this application in Vietnam have not yet been understood. This study measured the general perception of and willingness to pay (WTP) for using smartphone-based vaccination management applications and their associated factors in Vietnam. Subjects and methods: A cross-sectional study was conducted between March and April 2016 in an urban vaccination clinic at the Hanoi Medical University in Vietnam. Convenience sampling was used to recruit 429 adult participants who had received vaccinations or whose children were vaccinated. Sociodemographic characteristics and the acceptability of and WTP for using smartphone-based vaccination management applications were evaluated. Results: Among participants who used smartphone applications, 5% were aware of existing vaccination management applications, of whom 57.9% had previously used the applications. About 69.6% of participants believed that the applications were necessary, 93.7% of them were also willing to use the applications, and 79.1% were willing to pay 92.7 thousand Vietnamese dong (VND) for the applications on average. Participants who were older, unemployed, earned more household income, and having knowledge about functions and benefits of vaccination were less likely to use the vaccination applications. Participants who brought their children to get vaccinated at younger age and with higher level of education were willing to pay more for vaccination applications. Conclusion: High levels of acceptability of, willingness to use, and WTP for smartphone-based vaccination management applications among Vietnamese participants are reported. Increased education and awareness about the benefits of vaccination and vaccination management applications through community health workers might increase the feasibility of implementing such applications and perception toward their usage among young adult smartphone users. In addition, building a stronger relationship with health care providers at hospitals might improve the application’s visibility and adoption. Keywords: WTP, feasibility, smartphone, vaccine, management, Vietna

A Study on the Corrosion Behavior of 7072/3004/7072 Clad Aluminum Alloy in Different Media

Cladding is an easy and economical method to design multifunctional aluminum structures with improved corrosion resistance, mechanical strength, and physical appearance. In this study, the electrochemical properties and corrosion behavior of an aluminum-clad product made of 7072/3004/7072 aluminum alloys were investigated by Tafel extrapolation and impedance spectroscopy. 3004 aluminum sheet was used as core, and it was cladded with 7072 aluminum sheets on both sides. The long-term corrosion behavior of clad samples was examined after being immersed in tap water, rainwater, and 3.5 wt.% NaCl solution for 4 weeks. The results show that because of the potential difference between 7072 and 3004 aluminum alloys, 7072 alloy behaves more anodic and corrodes preferentially (with a slower rate) compared to 3004 aluminum alloy. Cladding 3004 with embossed 7072 alloy improves the corrosion resistance of the alloy. Moreover, the electrolyte comparison demonstrates that the carbonate-forming ions (such as Ca) in tap water and HCO3-, NO3-, and SO(4)(2-)in rainwater decelerate the corrosion rate