サンプリングテクニック

The district was purposively selected for this study since this area has largest　population of elderly in Thailand. Two-stage cluster sampling was employed to draw a sample. Six out of 25 sub-districts were chosen by simple random sampling technique.

Nakhon Ratchasima Province
↓				←	Purposively selected
Muang District 25 sub-districts
↓				←	simple random sampling
Sub dist 1	Sub dist 2	Sub dist 3	Sub dist 4	Sub dist 5	Sub dist 6
↓	↓	↓	↓	↓	↓	←	Simple random sampling
55	113	122	34	30	48
↓
402 VHVs

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