Table 1. Characteristics of the pooled cohort studies and participants.
| Cohort | Area | Participants characteristics | Baseline year | End of follow-up | Average follow-up years (SD) |
Sex | n | Age at baseline (year) | Smoking status at baseline (%) | |||
| Average (SD) | Range | Current | Former | Never | ||||||||
| JPHC-I | 5 public health center areas in Iwate, Akita, Nagano, Okinawa, and Tokyo prefectures |
Residents in each public health center area in the first 4 prefectures; participants of a health checkup in Tokyo Prefecture |
1990 | December 31, 2000 | 10.4 (1.6) | Male | 23,478 | 49.0 (6.0) | 40-59 | 12,589 (53.6%) | 5,428 (23.1%) | 5,461 (23.3%) |
| (One area†; 1990-1994) | Female | 26,561 | 49.1 (5.9) | 40-59 | 2,090 (7.9%) | 656 (2.5%) | 23,815 (89.7%) | |||||
| JPHC-II | 6 public health center areas in Ibaraki, Niigata, Kochi, Nagasaki, Okinawa, and Osaka prefectures |
Residents in each public health center area in the first 5 prefectures; participants of a health checkup in Osaka Prefecture |
1993-1994 | December 31, 2003 | 10.2 (1.7) | Male | 29,567 | 53.2 (8.8) | 40-69 | 15,383 (52.0%) | 7,246 (24.5%) | 6,938 (23.5%) |
| Female | 33,175 | 53.5 (8.9) | 40-69 | 2,435 (7.3%) | 502 (1.5%) | 30,238 (91.1%) | ||||||
| 3-pref | 10 cities, towns, or wards in Miyagi, Aichi, and Osaka prefectures |
Residents in each area | Feb. 1, 1983-Nov 1, 1985 | Jan. 31, 1993-Oct. 31, 1995 | 8.5 (2.7) | Male | 44,453 | 54.4 (10.2) | 40-79 | 25,699 (57.8%) | 11,164 (25.1%) | 7,590 (17.1%) |
| (One area‡ Dec. 1, 1990) | (One area‡ Feb. 28, 2000) | Female | 43,704 | 55.2 (10.5) | 40-79 | 5,188 (11.9%) | 1,631 (3.7%) | 36,885 (84.4%) | ||||
| JACC | 45 cities, towns, or villages in 18 prefectures* throughout Japan, except Shikoku district |
Residents in 22 areas; participants of a health checkup in 20 areas; combination of these two or atomic bomb survivors in the remaining 3 areas |
1988-1990 | December 31, 1999 | 9.9 (2.2) | Male | 42,528 | 57.3 (10.2) | 40-79 | 22,556 (53.0%) | 11,241 (26.4%) | 8,731 (20.5%) |
| Female | 53,370 | 57.3 (10.1) | 40-79 | 3,004 (5.6%) | 925 (1.7%) | 49,441 (92.6%) | ||||||
| Pooled | 9.6 (2.3) | Male | 140,026 | 54.1 (9.7) | 40-79§ | 76,227 (54.4%) | 35,079 (25.1%) | 28,720 (20.5%) | ||||
| Female | 156,810 | 54.5 (9.8) | 40-79§ | 12,717 (8.1%) | 3,714 (2.4%) | 140,379 (89.5%) | ||||||
JPHC: Japan Public Health Center-based prospective study, 3-pref: Three-prefecture cohort study, JACC: Japan Collaborative Cohort Study
*: Hokkaido, Akita, Ibaraki, Tochigi, Chiba, Kanagawa, Niigata, Yamanashi, Nagano, Gifu, Shiga, Kyoto, Hyogo, Wakayama, Tottori, Hiroshima, Fukui, and Saga prefectures
†: Katsushika area in Tokyo Prefecture.
‡: Izumi-otsu in Osaka Prefecture.
§: The age distribution (40-49, 50-59, 60-69, and 70-79 years old) of the pooled data was as follows; 35.9%, 35.3%, 21.3%, and 7.5% for males; 34.2%, 35.5%, 22.3%, and 8.0% for females.
SD: standard deviation