Funding for this research was provided by:
Kenya National Commission for Science, Technology and Innovation (NCST/5/003/065)
Received: 20 February 2017
Accepted: 18 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: The study was conducted according to the Helsinki Declarations. Ethical approval for the study was sought and granted from Kenyatta University Ethical Review Committee (PKU019/116 of 2012). Written informed consent either in English or Swahili was obtained from each participant before enrolment.
: Not applicable.
: The authors declare that they have no competing interests.
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