Study on Reliability of Health Statistics in Southeast Asian Countries

Seiji Ohsawa*
 Department of child development and environmental studies, Institute of Human Living Sciences

1. LOCUS OF THE PROBLEM OF HEALTH STATISTICS IN SOUTHEAST ASIAN COUNTRIES
    In recent years, research concerning statistics on health and medical care in developing countries has been conducted in a variety of forms by a wide range of bodies, including the World Health Organization (WHO) and other international institutions, universities, and research institutes. Behind this situation lies a budding realization that such statistics are indispensable as basic data needed for the formulation of health care planning, as well as that such statistics and the related interpretative know-how are effective means of orienting public administrative policy in such countries in a scientifically sound fashion. Under the banner of improved primary health care (PHC), WHO has been promoting a campaign to safeguard the health of, and assure at least the minimum r~quisite health care for, populations in developing countries or outlying regions. Such efforts must be under-pinned by indicators enabling evaluation of the low level of health in such areas as viewed from a PHC standpoint. Although WHO officials recognize the importance of health indicators for PHC in the context of health statistics, the reality is that the accuracy of health statistics tends to be poorer in areas with a greater need for PHC. As a conse-quence, it is more difficult to obtain reliable statistics to serve as the basis for decisions on the level of PHC aid required and of the nature of the PHC needs. This situation forms the background of the ongoing search for effective, practical health indicators.
    In recent years, this field as well has seen much application of technique of statistical (or numerical) analysis, including factor analysis, cluster analysis, and other types of multi-variate analysis. As is well known, this type of research approach involves the collection of great quantities of health (or medical) care indicators and related indicators over a wide range of countries (or regions). The data are then subjected to matrix processing on a single-year or time-series basis, and the findings are used to provide the basis for various analyses of the current status of health care and for drafting of administrative policy. In addition, the composite variable data derived from multi-variate _ analysis are often advanced as effective health indicators.
    Generally speaking, multi-variate tests upon the use of a broad (high-quantity) sampling and numerous variables. These features are the source of serious problems in the execution of research based on this approach concerning health and medical care in developing countries. This is because there is a great difference between such countries and advanced industrialized countries in regard to the handling of data. In the first place, a broad sampling is by no means a simple operation in de'veloping countries. The statisti-cal .system tends tC~ vary from country to country, and behind each statistical item lies a unique set of statistical systems.
    For example, there is a gap of 16.6 years between Indonesia and Japan in regard to female average life expectancy at birth. Nevertheless, it would be improper to conclude from this statistic alone that the Japanese live 16.6 years longer than Indonesians on the average. This is because a legitirnate comparison cannot be drawn between the two sets of nurneri-cal data, which were derived through completely different methods. However, extensive sampling ignores such distinctions by, in effect, performing the same data processing for Indonesia, Japan, and Bangladesh, for example. This violates the basic axiom that data handled in a parallel fashion must be capable of mutual comparison to begin with.
    Table 1 and table 21) present comparisons of statistics for medical facilities and personnel, respectively, in Japan and various Southeast Asian countries. The tables exemplify the great gap among the six countries in regard to the items of statistical survey. Even items that appear to afford a common basis of comparison, such as "health statistician" do not appear in statistics, despite the presence of such personnel in the national Ministry of Health and Welfare. This serves to illustrate the difficulty of making valid intercountry com pansons.
    There are also serious problems associated with preparation of the numerous variables needed for multi-variate analysis.
    Obviously, omissions are not desirable in constructing a data matrix. Generally, the quantity of samples with omissions rises along with the number of countries subjected to analysis. For this reason, the researcher attempts to select mainly indices that are less susceptible to omission. Unfortunately, most such indices concern population or economic statistics ; very few are deeply related directly to health or medical care. This kind of variable bias results in a particularly detrimental omission in the case of multivariate statistical analysis involving the extraction of common factor from variable relationships. The reason is'that the components or factors derived are bound to be removed from the actual health/medical realities, and the equations or expressions constructed from thern will be nothing more than abstractions.
    In other words, use of multi- variate analysis as a method of intercountry comparison and evaluation is apt to encounter two types of serious difficulties : 1) data incapable of legitimate cornparison are processed uniformly, in parallel, and 2) the data themselves do not accurately reflect the health/medical realities. As a result, the value of the findings of such analyses as the basis for effective action is likely to be low.
    The aim in the search for health indicators useful for PHC is, on the other hand, indices that can be readily applied in area/district activities and understood by the PHC personnel on the grass roots level to the point that such personnel could even prepare such statistics themselves, if necessary.
    WHO has asked researchers in the field of international health statistics for proposals of such indicators, but research in this aspect is limited, particularly in Japan, where such researchers are extremely rare and proposals of health indicators for PHC have been virtually non=existent.

2. RELIABILITY OF HEALTH STATISTICS IN DEVELOPlNG COUNTRIES
    The reliability of values derrved from measurement can be expressed as "T=M+E", where "T" rs the true value "M" Is the measured value and "E" is the error of the measured value. Mimnnzatron of "E" Is directly Imked to an mcrease m the reliability of the measured value. "E" stems from a mixture of various factors as far as health and medical statistics are concerned. The following is a description of some such factors common in the case of developing countries.

    l) Generally speaking, the statistical system in developing countries is a relic of policy of instruction, aid, or colonial administration imposed by the former suzerains. At the present time, developing countries are the subjects of vigorous programs of instruction implemented by various UN-affiliated agencies as well as of aid extended by advanced industrialized countries. In the countries behind such programs, censuses and surveys regarding their respective populations are conducted through statistical bureaus set up within the apparatus of the central government. By contrast, health statistics in various Southeast Asian countries are under the jurisdiction of health-related ministries, as is the case in Japan.
    Specialists are sent from WHO, other assistance organizations, and the governments of the various advanced industrialized countries to these ministries, to which they provide advice and aid concerning health statistics. Despite efforts extending over several dec-ades, however, this approach has not led to measures for fundamental improvement in the system of health statistics. Part of the problem is that, by its nature, this approach has bred a chronic dependence on foreign countries for expertise and technology as well as for financial and material assistance. In addition, the very presence of such foreign personnel in the country has tended to reduce inclinations of self-help. More recently, the introduc-tion of computers from foreign countries has acted to further widen the already existing lack of coordination between the hurnan and systemic organization.
    The statistical bureaus do contain specialized statisticians, and in most cases, these personnel have been promoted and are salaried in a manner cotnmensurate with their training. However, personnel specialized in the handling of health statistics are not to be found within the health ministries on the national level ; in most cases, these personnel have been trained as doctors. And since most of thern prefer promotion in another department or capacity to promotion as a statistician in a statistical one, they tend to be apathetic about remedy of the contradictions in the statistical system. This problem is therefore associated with the machinery of the central government, but it goes without saying that there are many similar problems related to the personnel who should be supporting the statistical system on the provincial level as well.
    In governmental administrative agencies, there is apparently a tendency to use the statistical levels for the work of the agency unit in question as a reference for the performance of personnel in it. That is, a worsening of performance as appears in statistics acts to delay the promotion of the personnel. For this reason, it is fairly common for provincial personnel to "improve upon" statistics or to neglect to report "unfavorable" statistics in the interests of their own promotion. In a certain Southeast Asian country, such practices have become virtually routine, and official statistics are almost devoid of reliability. Such statistics on the provincial level are collected and totalized on the national (central governrnent) Ievel before submission to UN-related agencies, which consequently are basically unable to determine where (central, provincial, or district) the national statistics were juggled, even if they detect impropriety. Last year, a citizen of Japan died from cholera "imported" from a developing country. The incident received great play in the Japanese mass media, which led to a dramatic declir}e in the number of Japanese tourists visiting the country in question. In response, the government of the country suppressed the submission of cholera-related statistics to UN-related agencies and other parties. Such statistical reports have been resumed since, but the official figures announced by the government are thought to be underestimates. In such cases, the central government itself is taking a hand in the statistical distortion.
    Abuses of this type are longstanding, and are associated with the fact that the preparation of accurate statistics in the final analysis depends on the conscientiousness of the preparers. As such, they are not likely to be eliminated without a wider diffusion of statistical traning, fundamental improvement of the morale of the preparers, and other measures that cannot be implernented overnight. In other words, 'however well-organized the statistical system and related legal framework, such abuses will be difficult to correct as long as the morale of the preparers is low.

    2) Another barometer of statistical reliability is the statistical dispersion. More specifically, the reliability of health statistics may be regarded as suspect when figures for a certain statistical item as viewed over a period of time exhibit jumps in certain years or extremely great variation, provided that there have been no commensurate outbreaks of contagious diseases, etc., in the years in question.

    3) In any country, population statistics are a vital item of concern in the context of the overall statistical administration. Even in Southeast Asian countries, population statistics tend to be more accurate that health statistics, and are contained in considerable detail in national statistical annuals and demographic reports. Nevertheless, the reliabil-ity of population statistics as well can by no means be termed high in absolute terms. In the developing countries, much birthsand deaths, go unreported. In addition, there is a great movement of population within the countries. Particularly, for example, notable is the influx of population into districts of Bangkok (the respective rates of population influx and efflux and over the years 1965-1970 were 12.4 and 9.8 percent for Phra Nakhon and 20.O and 5.0 percent for Thonburi3)). Moreover, the influx is concentrated in Bangkok's slums, making it more difficult to ascertain the actual population. The job is further complicated by the minority and semi-nomadic ethnic groups living on the borders with Burma, Laos, Cambodia, and Malaysia, and the population living on boats.
    Research in the area of health statistics requires accurate statistics concerning death and disease in order to ascertain the actual health situation. Unfortunately, the process of accurately counting cases of death and disease by cause/type is far more difficult than that of counting population. The process depends upon the subjective judgement of a third party (the doctor's diagnosis), and in some cases statistics are prepared without a proper diagnosis. Such cases are so numerous in the Philippines that the government has released mortality statistics classified into categories "medically certified" and "non-medically certified"'). (In the case in question, deaths in the latter category accounted for roughly half of the total.)
    Even in the case of "medically certified" deaths, there is a great variation in factors bearing upon the accuracy of the certification, including the qualification of the certifying doctor (specialist/non-specialist), Ievel of.- clinical test expertise, experience, depth of diagnosis before death, and whether or not an autopsy was performed. The level of knowledge concerning classification of causes of death is also an important influence. Moreover; in certain districts, a single doctor is accorded responsibility for certification of several hundreds of deaths daily in statistics, as will be related below. In such cases, it is thought that a considerable portion of the "certification" was in fact preformed by nurses, folk doctors, or monks.
    For such reasons, statistics concerning death and disease tend to be extremely unstable and to harbor many errors.
    These circumstances notwithstanding, the health situation of populations in such areas must be gauged by some method. Various medical indicators have been proposed in this connection. A particularly favorable rating has been garnered by the proportional mortality index (PMI ; the ratio of the number of deaths of those aged 50 or over to the total number of deaths), which is regarded as both simple to apply and highly effective. (It being difficult to obtain accurate statistics on causes of death in developing countries, use of PMI offers a reading of the prevalency of adult diseases. Generally, the higher the PMI, the longer the average life span, and by extension, the better the health situation of the population in question. The major virtue of this indicator is the fact that it can be easily applied as long as age information is available.)
 
Summary and conclusion
    The following can be cited as the main factors contributing to error and bias in health statistics in developing countries.
    1) The system for the pfeparation of statistics is underdeveloped, and there are serious problems related to the morale and quality of the corps of personnel handling statrstics.
    2) Statistical items and units are not entirely uniform, making it difficult to conduct international and historical (time-series) comparisons.
    3) There are many omissions to form official notifications and registrations.
    4) The reliability of those health statistics related to cause of death and disease type is particularly low, making them unusable in many cases.

REFERENCES
    1) SEAMIC Health Statistics 2002, Southeast Asia Medical Information Center, 2003, Tokyo.
    2) Statistical Reports of Changwat (Ubonrachatani), National Statistical Office, Office of the Prime Minister, Thailand, 1979, 1985.
    3) Internal Migration of Thailand, 33 p., Asia Economics Research Institute, 1981.
    4) Philippines Health Statistics, Ministry of Health, Philippines, 1974.

摘要
筆者は発展途上国特に東南アジア諸国の保健統計を過去20年間にわたって編集してきたが本論では以下の問題点,反省点を明らかにした.    1)統計を扱う要員 の訓練をはじめモラルの向上や彼ら自身への統計教育が不可欠で緊急の課題である.
    2)統計標識,統計単位,用語の定義が域内各国で不統一のため比較可能性 が低い.
    3)届出,中告漏れ等調査上,届出上の誤差が大きい.
    4)WHOの統計概念が末端まで徹底しておらず一国内においてさえも統計標識,概念の翻齢が うかがえる.年次比較でさえ困難をきたしている.

Table1  Comparative Table on Methods Establishments

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Table2 Comparative Table on Medical and Allied Health Personnel

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