Conditions vary very widely in the ASEAN region, and the circumstances of the region's elderly vary accordingly. This section will therefore provide a brief overview of these characteristics. Two main sources of information will be used: national censuses and surveys in which the elderly are enumerated along with the rest of the population; and special surveys of the elderly conducted in each country as part of the project on the Socio-Economic Consequences of the Ageing of the Population (hereafter referred to as ASEAN Ageing Surveys). The latter provide a unique set of data on many aspects of the family situation, living conditions, income, health, and recreation of the aged.

Differences between these two sources of data should be briefly noted. Firstly, the censuses refer to 1980 but the ASEAN Ageing Surveys to 1986 (except for the Philippines, where the survey was conducted in 1984). But more importantly, the censuses give either a complete count or a representative sample of all the elderly in the country, whereas among the ASEAN Ageing Surveys this is true only for Singapore and Thailand. In Malaysia, the survey is representative of the elderly in three west coast states of Peninsular Malaysia — Selangor, Negeri Sembilan, and Melaka. In Indonesia and the Philippines, the sample was chosen to give a broad cross-section of the elderly in various geographic areas and socio-economic groups, without any pretence at statistical representativeness. In Indonesia, the survey was confined to Java, which contains just over 60 per cent of the nation's population. Further details about sampling are given in the Appendix.

One limitation of the surveys is the omission of the elderly whose physical and mental conditions prevent them from being interviewed. This bias, however, is shared by virtually all research on the elderly (Treas and Logue 1986). Another limitation is the omission of the elderly who live in institutions, but this is not a serious omission as only a tiny proportion of the region's elderly live outside a household context.