Received: 4 April 2019
Accepted: 19 June 2019
First Online: 4 July 2019
Ethics approval and consent to participate
: Only de-identified data were obtained from the DHS survey program. This study therefore obtained a human subjects exemption from the institutional review board at Harvard University (protocol number IRB16–0515). This research was conducted without patient or public involvement. Patients and the public were not directly involved in the development of the research question, outcome measures, or study design. Patients did not contribute to the interpretation of the results or to the writing or editing of this document.
: Not applicable.
: All authors declare that they have no competing interests.