Interviewer instructions
Information on the month and year of birth is important to improve the accuracy of age defects. Writing month and year based on the Christian calendar. Ask and write down the month and year of birth of the respondent. Fill in the month and year in the box provided. If the respondent only knows the year of his birth, write down the year while the month of birth is filled with 99. If the respondent does not know the year of birth, the available box is filled 9999.