| Abstract: | Depending on the different purposes of population surveys, different sample sizes are required for accurate results. Using statistical methods, sample sizes for different types of population surveys for the Chinese population are estimated. Thus, to insure at least 90% accuracy, a sample size of 830,000 is required for marriage and birth rates and a sample size of 7.8 million for population age distribution. For population surveys on age specific death rates, a sample size of 56.32 million is required for a 1-year retrospective study and a sample size of 11.26 million required for a 5-year retrospective study. In the past, certain population studies were undertaken with no consideration for sampling errors. Sample sizes for surveys on age specific death rates and population age distribution were too small, leading to results that did not represent the total population. On the other hand, sample sizes for marriage and birth conditions were too large, resulting in waste in manpower, materials, and time. Statistical calculations are given. |
