Table 3.
Results of traditional meta-analysis and meta-regression analyses of time in the therapeutic range
| |
|
Time spent in therapeutic range |
||
|---|---|---|---|---|
| Study-level factors | No. (%) | Unadjusted pooled mean upon subgroup analysis, % (95% CI) | Adjusted difference, % (95% CI) | p-v alue |
| All study groups |
78 (100) |
61 (59 to 62) |
NA |
NA |
| Study setting |
|
|
|
|
| AC Clinic |
25 (32.1) |
64 (62 to 66) |
7.2 (3.2 to 11.2) |
<0.001 |
| RCT |
26 (33.3) |
63 (61 to 65) |
9.1 (4.3 to 13.9) |
<0.001 |
| Community |
27 (34.6) |
55 (52 to 59) |
Referent |
|
| Study year |
|
|
|
|
| 1990-2000 |
10 (12.8) |
53 (46 to 61) |
−4.3 (−10.2 to 1.6) |
0.16 |
| 2001-2007 |
34 (43.6) |
64 (62 to 65) |
2.2 (−1.7 to 6.1) |
0.28 |
| 2008-2013 |
34 (43.6) |
60 (57 to 63) |
Referent |
|
| Interpolation method |
|
|
|
|
| NR/Other |
11 (14.1) |
63 (60 to 65) |
−2.1 (−6.8 to 2.6) |
0.38 |
| Linear |
67 (85.9) |
60 (59 to 62) |
Referent |
|
| Self-management |
|
|
|
|
| No |
77 (98.7) |
60 (58 to 62) |
−6.8 (−23.7 to 10.1) |
0.43 |
| Yes |
1 (1.3) |
72 (68 to 77) |
Referent |
|
| Geographic region |
|
|
|
|
| Europe/UK |
35 (44.9) |
67 (64 to 69) |
9.7 (6.0 to 13.4) |
<0.001 |
| Asia |
3 (3.8) |
47 (44 to 49) |
−5.5 (−14.7 to 3.7) |
0.24 |
| Other |
1 (1.3) |
49 (46 to 52) |
−3.0 (−16.1 to 10.1) |
0.65 |
| Multinational |
13 (16.7) |
61 (57 to 65) |
1.8 (−4.1 to 7.7) |
0.55 |
| North America |
26 (33.3) |
55 (50 to 60) |
Referent |
|
| VKA experience |
|
|
|
|
| NR/Mixed |
21 (26.9) |
54 (49 to 60) |
−4.6 (−8.3 to −0.9) |
0.02 |
| No |
17 (21.8) |
63 (60 to 66) |
−5.3 (−9.6 to −1.0) |
0.02 |
| Yes |
40 (51.3) |
63 (60 to 66) |
Referent |
|
| Duration of VKA treatment |
|
|
|
|
| ≥1 year |
59 (75.6) |
62 (60 to 63) |
2.7 (−1.7 to 7.1) |
0.23 |
| <1 year | 19 (24.4) | 58 (52 to 65) | Referent | |
AC = anticoagulation; CI = confidence interval; NA = not applicable; No. = number of study arms; NR = Not Reported; RCT = randomized controlled trial; UK = United Kingdom, VKA = Vitamin K Antagonists.