Text and Data Mining valid from 2019-03-12
Received: 10 September 2018
Accepted: 21 February 2019
First Online: 12 March 2019
Ethics approval and consent to participate
: This retrospective study was conducted with the approval and authorization of the Ministry of Health of Bénin. The access to the database was authorized by the Ministry of Health and all data analysed were anonymized.
: Not applicable
: The authors declare that they have no competing interests.
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