Received: 20 June 2018
Accepted: 3 May 2019
First Online: 11 June 2019
Ethics approval and consent to participate
: Before the commencement of the study, a letter of approval to conduct the study was sought by the authors and was provided by the Tongji Medical College, Huazhong University of Science and Technology institutional ethical review. Approval to conduct the research in secondary schools has been granted by Regional Administrative Secretary (RAS) of the respective regions in Tanzania. Permission has been granted by respective secondary school authorities.Participants were informed about the purpose of the study, and they were assured that their answers would only be used anonymously for research purposes on a voluntary basis.All participants aged 18 and above were given information about the study, and they were asked for their voluntary participation. A written informed consent was administered to each participant; all participants read and signed written consent forms before being enrolled in the study.For students under 18 years old, consent (agreement to participate in study) was sought and obtained from their parents or guardians.
: Not applicable
: The authors declare that they have no competing interests.
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