| 2003 | 2005 | ||||
| Before training (n = 216)n (%) | 3 months after training (n = 216)n (%) | 2 years after training (n = 216)n (%) | Control (n = 454)n (%) | Total (n = 670)n (%) | |
| Experience of new working methods: use/no use | |||||
| Have not used the tools (total) | 107 (49.5) | 40 (18.5) | 238 (52.4) | 278 (41.5) | |
| Not enough instruction | 51 (23.6) | 0 (0) | 15 (3.3) | 15 (2.2) | |
| Work task too small | 27 (12.5) | 24 (11.1) | 72 (15.9) | 96 (14.3) | |
| No time for training | 19 (8.8) | 6 (2.8) | 26 (5.7) | 32 (4.8) | |
| Takes too long | 11 (5.1) | 2 (0.9) | 18 (4.0) | 20 (3.0) | |
| Tools not good enough | 8 (3.7) | 2 (0.9) | 10 (2.2) | 12 (1.8) | |
| Want to do as usual | 4 (1.9) | 12 (5.6) | 84 (18.5) | 96 (14.3) | |
| Have used the tools (total) | 107 (49.5) | 176 (81.5) | 216 (47.6) | 392 (58.5) | |
| Work goes faster | 64 (29.6) | 115 (53.2) | 113 (24.9) | 228 (34.0) | |
| Easy to use | 52 (24.1) | 130 (60.2) | 136 (30.0) | 266 (39.7) | |
| Fewer health problems | 39 (18.1) | 104 (48.1) | 93 (20.5) | 197 (29.4) | |
| Not enough instruction | 19 (8.8) | 2 (0.9) | 23 (5.1) | 25 (3.7) | |
| Work task too small | 12 (5.6) | 55 (25.5) | 72 (15.9) | 127 (19.0) | |
| Want to do as usual | 2 (0.9) | 5 (2.3) | 15 (3.3) | 20 (3.0) | |
| Use of new working methods | |||||
| Never | 107 (49.5) | 18 (8.3) | 39 (18.1) | 242 (53.3) | 281 (41.9) |
| Occasionally | 73 (33.8) | 77 (35.6) | 92 (42.6) | 128 (28.2) | 220 (32.8) |
| Weekly | 15 (6.9) | 60 (27.8) | 64 (29.6) | 56 (12.3) | 120 (17.9) |
| Daily | 6 (2.8) | 20 (9.3) | 19 (8.8) | 16 (3.5) | 35 (5.2) |
| Missing | 15 (6.9) | 41 (19.0) | 2 (0.9) | 12 (2.6) | 14 (2.1) |
| Never | 33 (15.3) | 242 (53.3) | 275 (41.0) | ||
| <1 year | 42 (19.4) | 102 (22.4) | 144 (21.5) | ||
| ⩾1 year | 140 (64.8) | 101 (22.3) | 241 (36.1) | ||
| Missing | 1 (0.5) | 9 (2.0) | 10 (1.5) | ||
| Knee complaints during the previous 12 months | |||||
| Use of new working methods | |||||
| Never | 21/39 (53.8) | 16/30 (53.3 | 23/39 (59.0) | 139/242 (57.4) | 162/281 (57.7) |
| Occasionally | 53/92 (57.6) | 47/76 (61.8) | 59/92(64.1) | 83/128 (64.8) | 142/220 (64.5) |
| Weekly | 34/63 (54.0) | 25/51 (49.0) | 41/64 (64.1) | 32/56 (57.1) | 73/120 (60.8) |
| Daily | 7/19 (36.8) | 8/15 (53.3) | 10/19 (52.6) | 9/16 (56.3) | 19/35 (54.3) |
| p = 0.434* | p = 0.535* | p = 0.765* | p = 0.543* | p = 0.388* | |
| Never | 18/33 (54.5) | 18/33 (54.5) | 135/242 (55.8) | 153/273 (56.0) | |
| <1 year | 24/42 (57.1) | 32/42 (76.2) | 73/102 (71.6) | 105/144 (72.9) | |
| ⩾1 year | 74/139 (53.2) | 84/140 (60.0) | 56/101 (55.4) | 140/241 (58.1) | |
| p = 0.905* | p = 0.100* | p = 0.019 | p = 0.002 | ||
| Knee complaints >30 days during previous 12 months | |||||
| Use of new working methods | |||||
| Never | 15/39 (38.5) | 14/39 (35.9) | 49/242 (20.2) | 63/280 (22.5) | |
| Occasionally | 34/92 (37.0) | 22/92 (23.9) | 36/128 (28.1) | 58/219 (26.5) | |
| Weekly | 22/61 (36.1) | 11/64 (17.2) | 15/56 (26.8) | 26/119 (21.8) | |
| Daily | 5/19 (26.3) | 4/19 (21.1) | 3/16 (18.8) | 7/35 (20.0) | |
| p = 0.820* | p = 0.172* | p = 0.304** | p = 0.647* | ||
| Never | 12/33 (35.4) | 10/33 (30.3) | 50/242 (20.7) | 60/271 (22.1) | |
| <1 year | 16/41 (39.0) | 14/42 (33.3) | 34/102 (33.3) | 48/144 (33.3) | |
| ⩾1 year | 48/137 (35.0) | 27/140 (19.3) | 19/101 (18.8) | 46/240 (19.2) | |
| p = 0.896* | p = 0.104* | p = 0.022* | p = 0.005* | ||
| Reduced† knee complaints during the previous 12 months | |||||
| Use of new working methods | |||||
| Never | 1/29 (3.4) | 0/39 (0) | 18/242 (7.4) | 18/281 (6.4) | |
| Occasionally | 14/75 (18.7) | 5/92 (5.5) | 11/128 (8.6) | 16/220 (7.3) | |
| Weekly | 12/50 (24.0) | 8/64 (12.5) | 8/56 (14.3) | 16/120 (13.3) | |
| Daily | 4/14 (28.6) | 5/19 (26.3) | 0/16 (0) | 5/35 (14.3) | |
| p = 0.109* | p = 0.003* | p = 0.234* | p = 0.069* | ||
| Never | 1/23 (4.3) | 0/33 (0) | 15/242 (6.2) | 15/271 (5.5) | |
| <1 year | 6/31(19.4) | 2/42 (4.8) | 13/102 (12.7) | 15/143 (10.5) | |
| ⩾1 year | 24/116 (20.7) | 16/140 (11.4) | 9/101 (8.9) | 25/241 (10.4) | |
| p = 0.176* | p = 0.069* | p = 0.142* | p = 0.085* | ||
*χ2 for differences between groups.
†Reduced knee complaints were compared to no, unchanged, and more knee complaints.