Abstract
Women giving birth to infants at 59 health facilities in three regions of Mexico were surveyed. Five hundred forty-six mothers were questioned on admission to the hospital about their plans for infant feeding when they returned home; 485 were questioned again prior to discharge; and 160 were interviewed a third time at home two weeks after discharge about their actual feeding practices. The results of a formal structured questionnaire asking about plans to use any of six specific milk and non-milk substances that are fed by bottle were compared with those of a questionnaire methodology in which the interviewers probed the answers. The study identified a third problem in dealing with self-reported information, in addition to the previously identified problems of memory failure and recall bias - which did not arise here - that of differences between respondents’ perception of their behaviour and their actual behaviour. By supplementing a formal questionnaire with more probing and less structured questions, these biases can be lessened and more accurate data obtained.