1957 - United Nations Statistics Division

varies widely.I 9 This is due in part to lack of uniformity
in national legislation. In some areas, registration is compulsory
for only 2 or 3 of the five events; in others, it is
compulsory for only a part of the population (e.g., "European,"
"civilized" or "non-indigenous" population in
most African territories) . In other countries, such as India
and Pakistan, there is no provision for compulsory registration
on a national basis, but only municipal or state
ordinances which do not cover the entire geographic area.
Still other countries (e.g., Ghana, Indonesia) have developed
"registration areas" which comprise only a part of
the country, the remainder being excluded for reasons of
inaccessibility or because of economic and cultural considerations
that make regular registration a practical impossibility.
Examination of the tables will show that the vitalstatistics
coverage for Africa is particularly spotty, being
confined largely to data for the European population
with, as a rule, only a few partial statistics and estimates
for the indigenous segments. Similarly, the coverage is
uneven and the statistics incomplete for much of Asia
and parts of Latin America. This unevenness is one important
limitation to international comparability.
Completeness of data
In addition to the variations which arise because
of lack of uniformity in national legal provisions for registration,
there are also differences in the effectiveness with
which similar laws operate in the various countries. The
manner in which the law is implemented and the degree
to which the public complies with the legislation determine
the completeness and accuracy of the statistics obtained
from the civil registers.
Quality code
Although deficiencies in the statIstICS are often fairly
obvious, evaluations of quality would of necessity tend to
be subjective when based only on the tabulated series. To
obtain more basic information on this point, the United
Nations in 1956 made a special inquiry as to the completeness
and accuracy of the data returned on the Demographic
Yearbook annual questionnaire. On the basis of
the replies from countries and in the light of the results
of a search of relevant official publications, it has been
possible to classify national vital statistics into three
broad categories, as follows:
(1) those stated to represent ::it least 90% coverage of
the events occurring each year; these are coded "C";
(2) those stated to represent incomplete, that is, less
than 90% coverage or to be subject to considerable irregularity
of registration; these are coded "U"; and
(3) those concerning which no specific information is
available, for which the symbol of three dots ( ... ) is
used.
The results of this classification appear in the first
column of the trend tables, Nos. 6, 7, 8, 9, 22 and 23
which show total frequencies and rates for live births,
deaths, infant deaths, divorces and marriages. Because no
precise information could be obtained, a code could not
be developed for foetal-death statistics (see p. 37).
19 For a regional analysis of the geographic and ethnic coverage of
birth and death statistics, see the 1956 Demographic Yearbook,
Chapter I, Table J, p. 15.
24
Applicability of code: Despite the fact that the code is
presented only in connexion with the trend tables, it is
of course applicable to recent vital statistics for the coun·
try in question wherever they appear in the Yearbook.
Thus, in using data from Tables 6-23, reference should
be made to the quality code before any comparisons or
analyses are attempted. In the case of the life-table functions
in Tables 24, 25, and 26, adjustments have usually
been made for deficiencies in the basic data.
Strictly speaking, the reliability code relates specifically
to the vital statistics and not to the population base used
in the computation of the rates. However, it should be
pointed out that the accuracy of the two components of
the rate is interrelated, particularly where vital statistics
have been utilized in the preparation of the population
estimates. A fuller evaluation of current rates may be
made by referring also to the "type" code on the 1956
population estimates presented in Table 1.
It is important to remember also that, although in a
number of cases the statistics maintain a high degree of
accuracy throughout the period covered, in general, the
code is consistently applicable only to recent data. In the
earlier years, many of the series were considerably less
reliable than the code implies.
Information on the quality of the vital statistics is lacking
for a number of areas, but it is safe to assume that, for
many of these, reliability is open to serious question. 20
An examination of the computed or implied rates for
these areas will sometimes indicate the cases for which a
presumption of incompleteness is probably justified.
However, this technique applies only where the data are
markedly deficient and where they are tabulated by
date of occurrence; tabulation by date of registration
will often produce rates which are large enough to appear
correct, simply by including therein many delayed
registrations. Moreover, it should be remembered that
knowledge of "expected" levels of fertility, mortality,
and nuptiality is extremely scanty for many parts of the
world and that borderline cases, which are the most
difficult to appraise, are frequent. In view of these considerations,
the symbol of three dots ( ... ) in the code
column ought to be taken as a warning that the accompanying
data should be approached with caution.
Improvement in the coverage of vital events through
increasing registration completeness is a limiting factor
to comparability over time. Such improvement tends to
mask actual trends in the incidence of birth, death, or
marriage. For example, a steadily rising crude birth or
death rate is quite likely to indicate improvement in completeness
of registration rather than a rise in fertility or
mortality. Rising stillbirth ratios are also likely to be a
function of improved registration. Furthermore, temporary
measures such as the removal of registration fees
in order to encourage compliance may cause the frequencies
to rise sharply in certain years; where tabulations
include delayed registrations, the fluctuations may
be particularly violent. When factors of this type are
known to be operating, they are noted in the tables. As
the information given in the code column and in the
footnotes makes clear, some of the material presented in
the tables is useful not as a measure of actual levels and
changes but rather as an indicator of where registration
20 See the 1956 Demographic Yearbook, Chapter I, p. 15-16 for an
analysis of the code by regions.