Funding for this research was provided by:
Secretaria de Salud, México (SN)
Text and Data Mining valid from 2018-08-01
Received: 27 June 2017
Accepted: 11 April 2018
First Online: 1 August 2018
Ethics approval and consent to participate
: The procedures for contacting the households and informants, processing of the data, and publishing related information were approved and monitored by the International Review Board of the National Institute of Public Health in Mexico. All informants participated voluntarily, and their informed consent was obtained.
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