| Shanghai | Beijing | Wuhan | Xi'an | Guangzhou | Total |
---|---|---|---|---|---|---|
Total sample | 3153 (87.6%)a | 3171 (88.1%) | 3291 (91.4%) | 3266 (90.7%) | 3210 (89.2%) | 16 091 (89.4%) |
80% sub-sample | 2510 (87.2%)a | 2579 (89.5%) | 2615 (90.8%) | 2622 (91.0%) | 2546 (88.4%) | 12 872 (89.4%) |
• General information questionnaire |  |  |  |  |  |  |
• RDQ |  |  |  |  |  |  |
• Modified Rome II questionnaire |  |  |  |  |  |  |
20% sub-sample | 643 (89.3%)a | 592 (82.2%) | 676 (93.9%) | 644 (89.4%) | 664 (92.2%) | 3219 (89.4%) |
• General information questionnaire |  |  |  |  |  |  |
• RDQ |  |  |  |  |  |  |
• Modified Rome II questionnaire |  |  |  |  |  |  |
• SF-36 |  |  |  |  |  |  |
• ESS |  |  |  |  |  |  |
• Physical examination |  |  |  |  |  |  |