Age
P-12. How old is [person]? _ _
25.4 Column P12: Age
Age is one of the most important pieces of information to be sought in a census. You must try as much as possible to record the correct age of the respondent. Under no circumstances should this column be left blank. You must probe to make sure that you get even a rough estimate.
- Always start by asking the person's age and follow up with the question on the date of birth as a consistency check on the former. Write the person's age in completed years ? that is, the person's age at his or her last birthday. For babies under one year of age, write "0". Persons aged 95 years and over should be coded "95". Make sure always that your writing is legible and within the appropriate box.
- Be careful not to round ages up to the next birthday. A child who is aged four years and eleven months should, for example be entered as "4" and not "5".
- Many people do not know their ages. If a person's age is not known, you must make the best estimate possible.
- There are various ways in which you can estimate a person's age. Sometimes, people have documents, such as baptismal certificates, which show the year of birth, in which case it is easy to calculate age.
- Most people have identity cards showing when they were born. These ID cards may be grossly inaccurate for some of the older people. Avoid using the IDs as the sole means to estimate such a person's age. However, for persons below 50 years of age the ID cards may generally give a more accurate representation of age.
- Generally, it is not so easy to estimate age for members of the household if all of them are ignorant of their ages. Concentrate first on establishing the age(s) of one or two persons in the household. One reliable age may help in working out the ages of others if it is known whether they are older or younger and by how many years.
- It is sometimes possible to estimate a person's age by relating his or her birth to some notable historical event. With these instructions is a historical calendar of events (see appendix 1) which lists the dates of events in the history of districts. If the person can remember how old he/she was at the time of the event, you can work out the person's age.
- How to use the historical calendar of events to estimate the respondent's age:
- Ask how old the respondent was when that event occurred or how many years elapsed before his/her birth.
- Then use this information to work out his/her age. For example, if a respondent was about 15 years when Kenya attained her Independence, this person should be 15 + 45 (i.e. 12th Dec. 1963 to 24th August 2009) = 60 years. If this method fails, you should try the following approach.
- Ask whether he/she has heard about any of those events.
- If he/she has, ask him/her to give you an indication of how old he/she was when this event occurred or how many years elapsed before he/she was born.
- Then, from this information, work out his/her age.
- Some tribes have systems of 'age grades' or 'age sets' from which a person's age can be worked out. A person's age grade may only give a rough idea of his or her age since the same grade may have in it people of widely different ages, but it is better than nothing. Some tribes have grades for men but not for women, but you can often obtain an idea of a woman's age by asking which age grade of men she associated with, or which set her brothers belonged to and whether they are older or younger. Some age grades are listed in the calendar of events.
- If all else fails, then base your estimate on biological relationships. For instance, a woman who does not know her age but who has two or three children of her own is unlikely to be less than 15 years old however small she may look. You may then try to work out her age by the following methods:
- Determine the age of her oldest child.
- Ask her to give an estimate of her age at the birth of this child. However without further probing, you should not base your assumption on the oldest child who is presently living. There is the likelihood that in certain cases, the first child died or that the woman had miscarriages or stillbirths. Therefore, if the woman tells you that she had one miscarriage or stillbirth before the oldest living child was born, you should make your estimation from the year of the first miscarriage/still?birth or live birth.
- Only as a last resort should you estimate a person's age from his physical features. If you are obtaining information about an absent person from a third party then rely on the information given to you to estimate the absent person's age.
- When you have arrived at the best estimate you can make of a person's age, check that it is compatible with his or her relationship to others in the household. Obviously children cannot be older than their parents.
- Any estimate of age, however rough, is better than leaving the column blank. Do the best you can to report ages accurately.