Table 1.
Participants and Data Structure
| Period | Year of entry to NSJE | Waves used for analysis (years of data collection) | Level 1: Number of observation sets; Wave (t-1) and Wave (t) | Level 2: Number of respondents | Level 3: Number of municipalities |
|---|---|---|---|---|---|
| A: Around 1990 | 1987, 1990 | Waves 1–4 (1987–1996) | 4,635 (t = 2, 3, or 4) |
2,030 | 192 |
| B: Around 2000 | 1996, 1999 | Waves 4–7 (1996–2006) |
3,527 (t = 5, 6, or 7) |
1,771 | 193 |
| C: Around 2015 | 2012 | Waves 8–9 (2012–2017) |
854 (t = 9) |
854 | 190 |
| Total | Waves 1–9 | 9,016 | 4,655 | 575 |
Notes: NSJE = National Survey of the Japanese Elderly. The years under “Period” (1990, 2000, and 2015) were based on the year of the Population Census used for municipality data.