The age of both mothers and their children is relevant here. Information on age in completed years was collected in the household schedule for all persons listed in the schedule. These data were obtained in response to the following question which came after recording the name, sex and residential type: 'how old is he/she?'; space for two columns was provided in the schedule to record the age in years. The WFS experience was that this kind of approach could lead to errors in age reporting, and WFS suggested that when only the age is collected the phrase 'completed years’ needs to be added as it will remind the interviewer to record the age in completed years (Jemai and Singh,
1987:131).
The SLDHS interviewers were, however, asked wherever possible to obtain the date of birth and calculate the age of the individual in completed years. To enable the interviewers to estimate the age accurately and easily from the reported date of birth, an age determination table was designed for the use of the interviewers. The interviewers were particularly advised to probe for the date of birth when recording ages of females who reported ages around the extremes of the eligibility criteria, to avoid the possibility of eligible respondents being missed or others being included as eligible through misreporting of ages at and around the ages 15 and 49.
The age distribution of the females derived from the SLDHS household schedule was compared with that of the 1984 estimates and found to be virtually identical between ages 15 and 35; slight deviations were noted in the rest of the age groups 35-49 (Department of Census and Statistics, 1988: 14).
2.10.1 Respondent's age
The errors in reporting one's own date of birth can be used to demonstrate not only the quality of age data but also the quality of some other pieces of information: if a woman
cannot accurately report her age she is more likely (though not necessarily) to misreport times and durations of other events as well. In the SLDHS, any respondent who was unable to report the exact date of birth was probed for her age. Of the total women in the anthropometric sample 91 per cent were able to report the complete date of birth with the year and month of birth while a further 5.4 per cent reported both year of birth and their age. Thus it was only in about 3 per cent of the cases that the ages of respondents (mothers) had to be estimated or imputed. Although the ability to report both year and month of birth does not necessarily mean high quality age data this information is used to examine the variation in the pattem of age reporting by various socio-economic groups. This is attempted in Table 2.2.
The proportion of women reporting complete date of birth varies according to the socio-economic background of the respondent: urban women reported date of birth better than rural and estate women. Estate women, surprisingly, show a modestly higher proportion of reporting for both year and month of birth than rural women. The observed reporting pattern of the estate population may be due to the citizenship requirements: almost all Indian Tamil respondents in the anthropometric sample may have been bom in Sri Lanka and by the time they were bom the majority of them were considered children bom to parents who were 'stateless'. Therefore it is quite natural to register these births as the possession of a birth certificate is essential documentary evidence for claiming citizenship.
The proportion of women reporting both year and month of birth increases progressively with level of education: 69 per cent of women with no schooling reported both, whereas virtually all women with higher education fully reported year and month of birth. Women categorized under 'other religion’ tend to report date of birth more completely than the others. The differentials observed are not statistically significant.
Age reporting in each of the residential sectors if examined controlling for the level of education, it is seen that women with secondary or higher education tend to report both year and month of birth irrespective of where they live. Of women living in urban and rural areas the percentage reporting complete date of birth varies with the
Table 2.2 Per cent of mothers reporting both year and month of birth according to socio-economic characteristics (weighted data)
Socio-economic characteristic
No.of women
Per cent reporting
both year year and
and month age
All women 1923 90.9 5.4 Residential type Urban 260 97.2 1.4 Rural 1544 89.9 5.9 Estate 119 90.8 7.4 Years of schooling No schooling 169 68.6 12.3 1-5 556 83.4 11.0 6-9 706 96.1 2.9 10 & above 492 99.5 0.2 Religion Buddhists 1585 91.6 5.0 Hindu 113 85.4 8.7 Christians 103 83.5 10.3 Others 122 93.9 2.9
Years of schooling & residential type No schooling and: Urban 9 70.0 10.0 Rural 117 59.4 15.8 Estate 43 93.1 3.2 1-5 years and Urban 50 92.5 3.7 Rural 449 82.1 11.6 Estate 57 86.1 13.1
Above Primary and
Urban 202 99.6 0.4
Rural 977 97.1 2.1
Estate 19 100.0 ”
level of education: for urban women, it increases from 70 per cent of those without any schooling to 93 per cent among women with primary level of education and reach almost 100 per cent for those with secondary or higher education. The rural women demonstrate a similar pattern but their percentages are consistently lower than those of
urban women for each educational category. Pattem of age reporting among the estate women according to the educational level is less clear because of the citizenship formalities described above.
2.10.2 Birth history and age of child
For each respondent interviewed, the SLDHS probed for her cumulative fertility or the children she had ever borne. Those who answered affirmatively were asked about the number of sons and daughters who were currently living with them, sons and daughters who were living elsewhere, sons and daughters not living now, and the total number of children living with them and living elsewhere and total number of children dead. From the responses to these questions, the total number of children ever bom and total number of children surviving (or dead) were determined.
Thereafter the survey recorded for each birth, beginning from the first birth, information such as name, sex, date of birth, survival status, age at death if not living, and age of living children. After recording the total live birth history, the interviewer counted the total number of children listed, the total number of children recorded as
living and dead and compared these totals with those recorded previously. Any
discrepancy was probed into and necessary corrections were made. This approach was, in fact, found to be very useful and assisted the respondent to report and the interviewer to record the complete birth history as accurately as possible.
The birth history data yielded an average number of children bom to a woman as 3.0 and a total fertility rate of 2.7 for the period 1984-1987, which were in conformity with the expected rates. For the SLDHS sample as a whole, in about 5 per cent of the
cases the complete date of birth of children was not given. In the case of the
anthropometric sample, children were identified for measurements based on the reported date of birth; among them there were only two cases where month of birth was not stated in the schedule and which were therefore eliminated from the data file (Department of Census and Statistics, 1988:112).
data are expected to be of good quality since problems of recall lapses and forgetting are very much less likely to affect the reporting of events and dates. The single-month distributions of the child population (3-36 months old) examined did not show any evidence of age heaping (distributions not shown here). A similar conclusion was made by others who examined the age data of the SLDHS anthropometric sample (Rutstein and Summerfelt, 1989:4).