Table 1.
Characteristics of the reviews and provided information about the included primary studies
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|
n = 50 reviews |
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|---|---|---|---|---|---|---|---|---|---|---|---|
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Item: |
Description of item: |
|
|
Yes |
No |
Unclear |
Not applicable |
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| N | % | N | % | N | % | N | % | ||||
|
Section 1: Information about the objective and design of the reviews |
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| 1. |
Type of primary studies included |
n = 50 (%) |
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|
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|
|
|
| |
Only outcome prediction models |
14 |
(28.0) |
|
|
|
|
|
|
|
|
| |
Combination of prognostic factor & outcome prediction studies |
3 |
(6.0) |
|
|
|
|
|
|
|
|
| |
Unclear |
33 |
(66.0) |
|
|
|
|
|
|
|
|
| 2. |
Is the outcome of interest clearly described? |
|
|
47 |
(94.0) |
1 |
(2.0) |
2 |
(4.0) |
|
|
| 3. |
Is information about quality assessment provided? |
|
|
36 |
(72.0) |
14 |
(28.0) |
|
|
|
|
| 3a. |
Method used |
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|
|
|
|
|
|
| |
Methodological criteria list |
3 |
(6.0) |
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|
|
|
|
|
|
| |
Individual items |
2 |
(4.0) |
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|
|
|
|
|
|
|
| |
Not applicable |
14 |
(28.0) |
|
|
|
|
|
|
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| |
Methodological criteria & study design |
31 |
(62.0) |
|
|
|
|
|
|
|
|
| 4. |
Was study quality accounted for |
|
|
21 |
(42.0) |
13 |
(26.0) |
2 |
(4.0) |
14 |
(28.0) |
| 4a. |
Method used *# |
n = 23 (%) |
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| |
Exclusion of poor quality studies (cut-off score used) |
3 |
(13.0) |
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|
|
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|
|
| |
Sensitivity analysis based on total quality score |
5 |
(21.7) |
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|
|
|
|
|
|
|
| |
Levels of evidence |
12 |
52.2) |
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|
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| |
Subgroup analysis |
7 |
(30.4) |
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|
|
|
|
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| |
Study findings weighted for quality |
3 |
(13.0) |
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|
|
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Other |
2 |
(8.7) |
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|
|
|
|
|
|
|
|
Section 2: Information about the design and results of the primary studies |
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| 5. |
Outcomes clearly described |
36 |
(72.0) |
20 |
(20.0) |
4 |
(8.0) |
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|
||
| 6. |
Statistical methods used for variable selection described |
2 |
(4.0) |
46 |
(92.0) |
2 |
(4.0) |
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||
| 7. |
Treatments described |
6 |
(12.0) |
37 |
(74.0) |
7 |
(14.0) |
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||
| 8. |
Univariable point estimates for all the variables of the primary studies are provided |
5 |
(10.0) |
42 |
(84.0) |
3 |
(6.0) |
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||
| 8a. |
Univariable estimates for dispersion for all the variables of the primary studies are provided |
5 |
(10.0) |
42 |
(84.0) |
3 |
(6.0) |
|
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||
| 9. |
All variables (starting predictors) used to develop a model are described |
4 |
(8.0) |
36 |
(72.0) |
10 |
(20.0) |
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||
| 10. |
Multivariable point estimates for each predictor in the final outcome prediction model are provided |
11 |
(22.0) |
33 |
(66.0) |
4 |
(8.0) |
2 |
(4.0) |
||
| 10a. |
Multivariable estimate of dispersion provided for each predictor in the final outcome prediction model |
11 |
(22.0) |
33 |
(66.0) |
4 |
(8.0) |
2 |
(4.0) |
||
| 11. |
Model performance is assessed and described |
7 |
(14.0) |
38 |
(76.0) |
2 |
(4.0) |
3 |
(6.0) |
||
| 12. |
number of events per variable is described |
4 |
(8.0) |
44 |
(88.0) |
2 |
(4.0) |
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||
|
Section 3: Data-analysis and synthesis in the reviews |
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| 13. |
Heterogeneity between studies described |
45 |
(90.0) |
4 |
(8.0) |
1 |
(2.0) |
|
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| 14. |
Qualitative data-synthesis presented |
49 |
(98.0) |
1 |
(2.0) |
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| 14a. |
Method used |
n = 49 (%) |
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Statistical significance |
22 |
(44.9) |
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| |
Consistency of findings |
7 |
(14.3) |
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| |
Consistency of findings & statistical significance |
6 |
(12.2) |
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| |
Available method of defining levels of evidence |
3 |
(6.1) |
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| |
Consistency of findings & levels of evidence |
3 |
(6.1) |
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other combinations |
8 |
(16.3) |
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|
|
|
|
|
|
| 15. |
Quantitative analysis performed |
|
|
10 |
(20.0) |
40 |
(80.0) |
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| 15a. |
Method used |
n = 10 (%) |
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|
|
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| |
Random effects model |
4 |
(40.0) |
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|
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| |
Fixed effects model |
1 |
(10.0) |
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| |
Random & Fixed effects model |
3 |
(30.0) |
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| |
Other |
2 |
(20.0) |
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| |
|
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|
n = 10 reviews |
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| 15b. |
Statistical heterogeneity assessed |
|
|
4 |
(40.0) |
6 |
(60.0) |
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| 15c. |
Method used to assess statistical heterogeneity |
n = 4 (%) |
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| |
I2 |
2 |
(50.0) |
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|
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| |
I2 & Chi2 |
1 |
(25.0) |
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|
|
|
|
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|
| |
Other |
1 |
(25.0) |
|
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| |
|
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|
n = 50 reviews |
|||||||
| 16. |
Graphic presentation of results provided |
|
|
8 |
(16.0) |
42 |
(84.0) |
|
|
|
|
| 16a. |
Method used |
n = 8 (%) |
|
|
|
|
|
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| |
Forest plot |
6 |
(75.0) |
|
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| |
Forest plot & scatter plot |
1 |
(12.5) |
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| |
Barplot |
1 |
(12.5) |
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|
|
|
|
| 17. |
Sensitivity analysis performed |
|
|
6 |
(12.0) |
43 |
(86.0) |
1 |
(2.0) |
|
|
| 17a. |
Method used |
n = 6 (%) |
|
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|
|
|
|
|
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|
| |
Different cut-offs for study quality |
3 |
(50.0) |
|
|
|
|
|
|
|
|
| |
Methodological criteria |
1 |
(16.7) |
|
|
|
|
|
|
|
|
| |
Methodological criteria & weights for quality |
1 |
(16.7) |
|
|
|
|
|
|
|
|
| Including other (excluded) cohorts | 1 | (16.7) | |||||||||
* includes ‘yes’ and ‘unclear’ categories.
# numbers and percentages may add up to more than 23 and 100%, due to multiple methods in some reviews.