روشهای مستقیم تخمین جمعیت

1. روشهای مستقیم تخمین جمعیت علی اکبر حقدوست، اپیدمیولوژیست

2. Direct methods Counting members of a target sub-population by direct contacting or direct observing www.hivhub.ir

3. Direct size estimation methods • Survey: Large scale cross-sectional study by selecting a random sample from the whole population • Census: counting all individuals of interest • Enumeration: counting a proportion of individuals of interest • Snowball technique (nomination method) www.hivhub.ir

4. Survey • Household survey is the best possible option but • It is prone to selection bias (absent groups) • It is prone to information bias • It is very difficult to implement because of the required sample size and logistics www.hivhub.ir

5. Census • Based on mapping, this method requires visiting every place of interest and counting members of the target population • It needs • High quality map • Well-trained researchers to know subjects • Executing the study in a brief period of time to avoid duplications (migrations) www.hivhub.ir

6. Enumeration • Enumeration method also focuses on counting individuals of interest • Based on mapping, a number of locations are chosen; members of a hidden population will be counted only on these chosen locations • The obtained number is then multiplied according to the size and structure of the sampling frame (provided by mapping) www.hivhub.ir

7. Snowball approach • A snowball-like (chain referral) method of identifying members of the target population; the size of population size has an association with the concept of saturation; but it has its own limitations such as • Double counting • Networking pattern • Mathematical computations www.hivhub.ir