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Table 1 Characteristics of the studies (n = 27)

From: Comparison of two data collection processes in clinical studies: electronic and paper case report forms

  

pCRFs n = 16

eCRFs n = 11

All n = 27

Design

Non-interventional studies

1 (6%)

4 (36.4%)

5 (18.5%)

Clinical trials

15 (94%)

7 (63.6%)

22 (81.5%)

Randomized

 

10 (63%)

7 (64%)

17 (63%)

Multicenter

 

10 (63%)

9 (82%)

19 (70%)

Geographic level

International/national

7 (44%)

8 (73%)

15 (56%)

Regional

9 (56%)

3 (27%)

12 (44%)

Purpose*

Diagnostic

1 (6%)

3 (27%)

4 (15%)

Observational

0 (0%)

2 (18%)

2 (7%)

Therapeutic

15 (94%)

6 (55%)

21 (78%)

Risk level α

A

2 (13%)

4 (36.4%)

6 (22%)

B

4 (25%)

3 (27%)

7 (26%)

C

3 (19%)

3 (27%)

6 (22%)

D

7 (44%)

1 (9%)

8 (30%)

Clinical trial phase

1

1 (7%)

0 (0%)

1 (4%)

2

4 (27%)

1 (14%)

5 (23%)

3

7 (47%)

6 (86%)

13 (59%)

4

3 (20%)

0 (0%)

3 (14%)

Median number of patients included*

 

60

355

80

Q1 = 27

Q1 = 78

Q1 = 50

Q3 = 141

Q3 = 700

Q3 = 500

Median number of centers

 

5

10

7

Q1 = 1

Q1 = 6

Q1 = 1

Q3 = 10

Q3 = 13

Q3 = 12

Median planned duration of study (months)

 

24

27

25

Q1 = 16

Q1 = 18

Q1 = 16

Q3 = 40

Q3 = 36

Q3 = 36

Median planned patient follow up (days)

 

137

60

91

Q1 = 67

Q1 = 12

Q1 = 30

Q3 = 365

Q3 = 112

Q3 = 213

Median number of variables in CRF

 

1,062

396

1011

Q1 = 669

Q1 = 153

Q1 = 286

Q3 = 1,118

Q3 = 1,567

Q3 = 1,126

Median number of variables in database β

 

65,928

304,929

76,692

Q1 = 18,764

Q1 = 35,250

Q1 = 20,088

Q3 = 171,646

Q3 = 625,865

Q3 = 304,929

Median number of full pages in CRF*

 

39

17

31

Q1 = 28

Q1 = 9

Q1 = 17

Q3 = 44

Q3 = 30

Q3 = 44

  1. *Significant difference between eCRFs and pCRFs (p < 0.05).
  2. αFrom level A = minimal, e.g. trial involving only additional blood sample collection, to D = major risk, e.g. trial of innovative therapies, phase I or II trials.
  3. βNumber of variables in database = number of patients x number of variables in CRF.