Background
Methods
Search strategy
Study eligibility
Data extraction
Limit of detection (LOD) calculation
Author,Year
|
Blood sample volume V1
|
Dilution volume V2
|
Elute used in PCR assay volume V3
|
Whole blood volume in each PCR reaction V4
|
LOD1 copies/PCR reaction
|
LOD2 copies/ml whole blood
|
---|---|---|---|---|---|---|
Barbi et al [10] | 50 | 25 | 2 | 4 | 2 | 500 |
Binda et al [11] | 40 | 45 | 10 | 8.89 | 4 | 449.9 |
Boppana et al [2] | 8 | 30a
| 5 | 1.3 | 1.56 | 1200d
|
Leruez-Ville et al [12] | 50 | 50 | 10 | 10 | 40 | 4000 |
Paradizˇ et al [13] | 16 | 100 | 20 | 3.2 | 4.15 | 1296 |
Scanga et al [14] | 50 | 100 | 10 | 5 | 8 | 1600 |
Soetens et al [16] | 50 | 25 | 5c
| 10 | 94 | 9400 |
Vaudry et al [15] | 50 | 50b
| 5 | 5 | 8 | 1600 |
Qualitative assessment
Test for heterogeneity
Sensitivity analysis
The influence of each trial for the outcome of the meta-analysis
| ||
---|---|---|
First Author (Year)
|
DOR
|
95%CI
|
Barbi et al [10] | 1350.5 | 532.0-3428.5 |
Barbi et al [8] | 1090.5 | 453.4-2623.0 |
Binda et al [11] | 1203.6 | 502.3-2884.3 |
Boppana et al [2] | 1396.4 | 501.6-3887.2 |
Boppana et al [2] | 1212.7 | 482.7-3046.9 |
Distéfano et al [24] | 1275.9 | 509.2-3197.1 |
Johansson et al [22] | 1566.9 | 651.6-3768.1 |
Leruez-Ville et al [12] | 1287.4 | 508.7-3258.3 |
Leruez-Ville et al [26] | 1243.8 | 495.8-3120.4 |
Paixão et al [25] | 1682.7 | 691.6-4094.1 |
Paradizˇ et al [13] | 1262.6 | 508.9-3132.5 |
Scanga et al [14] | 1432.5 | 576.3-3561.0 |
Soetens et al [16] | 1636.5 | 711.2-3765.3 |
Vaudry et al [15] | 1555.8 | 642.7-3765.9 |
Yamamoto et al [20] | 1357.9 | 536.4-3437.6 |
combined | 1262.6 | 508.9-3132.5 |
Statistical methods
Results
Eligible studies
Author [Reference]
|
Year
|
Location
|
Design
|
Total population screened
|
Inclusion criteria
|
Size of DBS used (diameter)
|
DBS stored temperature
|
Time of samples tested to collected
|
Type of DNA extraction
|
Type of PCR
|
Target region
|
Gold standard
|
---|---|---|---|---|---|---|---|---|---|---|---|---|
Barbi et al [10] | 1998 | Italy | Prospective | 205 | Universal screening | 3 disks (3mm) | UN | UN | Heat shock | Nested-PCR | UL55 | Viral isolation from saliva |
Barbi et al [8] | 2006 | Italy | Retrospective | 874 | Suspected of cCMV infection | 3 disks (3mm) | UN | UN | Heat shock | Real-time PCR | gB | Viral isolation from urine or saliva |
Binda et al [11] | 2004 | Italy | Retrospective | 195 | Suspected of cCMV infection | 3 disks (3mm) | UN | UN | modified Heat shock | Nested-PCR | gp58 | Viral isolation from urine,saliva or blood |
Boppana et al [2] | 2010 | America | Prospective | 11407 | Universal screening | 2 disks (3mm) | room temperature | 14.6±9.6days | Qiagen M48 robotic system | Single-primer Real-time PCR | gB | The DEAFF assay on the follow-up saliva/urine sample |
Boppana et al [2] | 2010 | America | Prospective | 9018 | Universal screening | 2 disks (3mm) | room temperature | 14.6±9.6days | Qiagen M48 robotic system | Two-primer Real-time PCR | gB & IE2 | The DEAFF assay on the follow-up saliva/urine sample |
Distéfano et al [24] | 2008 | Argentina | Retrospective | 145 | Compatible symptoms | UN | UN | UN | Heat shock | Nested-PCR | gB | Viral isolation from urine |
Johansson et al [22] | 1997 | Sweden | Retrospective | 31 | infants confirmed with/without cCMV and infants whose samples were stored close to the infetive ones | 25mm2 | 4°C | 12-18 years | Phenol-chloroform | PCR+hybridization test | OP1, OP2, IE1 | Viral isolation from urine |
Leruez-Ville et al [12] | 2009 | France | Retrospective | 214 | Compatible symptoms, Maternal PI | UN | UN | UN | QiAamp DNA Blood Mini kit (Qiagen) | Real-time PCR | UL123exon 4 | Urine culture/PCR |
Leruez-Ville et al [26] | 2011 | France | Prospective | 271 | Compatible symptoms, Maternal PI | whole spot (10mm) | standard conditions | After metabolic screening | QiAamp DNA Blood Mini kit (Qiagen) | Real-time PCR | UL123exon 4 | Urine sample PCR |
Paixão et al [25] | 2009 | Portuguese | Retrospective | 308 | Neonates confirmed with/without cCMV infection | UN | UN | UN | Heat shock | Nested-PCR | gp58 | Urine shell-viral culture |
Paradizˇ et al [13] | 2012 | Slovenia | Prospective | 2841 | Universal screening | 8 discs (2mm) | room temperature | 7 days | QiAamp DNA Blood Micro kit (Qiagen) | Real-time PCR | UN | Urine sample PCR |
Scanga et al [14] | 2006 | America | Retrospective | 19 | infants confirmed with/without cCMV and infants whose samples were stored close to the infetive ones | whole spot (10mm) | room temperature | 2-20 months | QiAamp DNA Blood Micro kit (Qiagen) | Real-time PCR | POL | Urine culture |
Soetens et al [16] | 2008 | Brussels | Retrospective | 67 | Universal screening | whole spot (10mm) | room temperature | 72.9±31 months (0.5-130 months) | Phenol chloroform | Conventional PCR + nested-PCR | US8 & gH | Urine culture |
Vaudry et al [15] | 2010 | Canada | Prospective | 95 | infants with VLBWs or SGA | UN | UN | about one month | MagaZorb DNA extraction Kit (Cortex Biochem) | CMV LC-real time PCR (Roche Diagnostic) | gB1, gB2 | Viral isolation from throat swabs |
Yamamoto et al [21] | 2001 | Brazil | Prospective | 332 | Universal screening | 3 disks (6mm) | -20°C | UN | Heat shock | Nested-PCR | MIE & gB/gB1 & IE | Urine sample viral culture and/or PCR |
Quality assessment
QUADAS-2 quality assessment
| |||||||
---|---|---|---|---|---|---|---|
Study (Year)
|
Risk of bias
|
Applicability concerns
| |||||
Patient selection
|
Index test
|
Reference standard
|
Flow and timing
|
Patient selection
|
Index test
|
Reference standard
| |
Barbi et al [10] | H | L | L | L | L | L | L |
Barbi et al [8] | H | ? | L | L | ? | ? | L |
Binda et al [11] | H | L | ? | L | L | H | L |
Boppana et al [2] | L | L | L | L | L | L | L |
Boppana et al [2] | L | L | L | L | L | L | L |
Distéfano et al [24] | H | L | L | L | L | L | L |
Johansson et al [22] | H | H | L | L | L | L | L |
Leruez-Ville et al [12] | H | ? | L | L | L | L | L |
Leruez-Ville et al [26] | H | L | L | L | L | L | L |
Paixão et al [25] | H | H | L | L | L | L | L |
Paradizˇ et al [13] | L | H | L | L | L | L | L |
Scanga et al [14] | H | H | L | L | L | L | L |
Soetens et al [16] | L | H | L | L | L | L | L |
Vaudry et al [15] | L | L | L | L | L | L | L |
Yamamoto et al [20] | L | L | L | L | L | L | L |
Test for heterogeneity
Screening performance
Subgroup analysis and meta regression
a. Subgroup analysis of study design and diagnostic accuracy
| ||||||||
---|---|---|---|---|---|---|---|---|
Study Design
|
N
|
I2(%)
|
P
|
Pooled sensitivity (95% CI)
|
Pooled specificity (95% CI)
|
Pooled LR+ (95%CI)
|
Pooled LR- (95%CI)
|
DOR (95%CI)
|
Prospective | 7 | 0.0 | 0.45 | 0.623 (0.548 - 0.693) | 0.999 (0.999 - 1.000) | 280.72 (60.026 - 1312.8) | 0.374 (0.182 - 0.768) | 1573.9 (699.17 - 3543.00) |
Retrospective | 8 | 64.0 | 0.01 | 0.945 (0.918 - 0.965) | 0.983 (0.974 - 0.989) | 43.831 (19.745 - 97.298) | 0.043 (0.007 - 0.280) | 1085.71 (229.94 - 5126.46) |
b. Subgroup analysis of LOD and diagnostic accuracy
| ||||||||
LOD
|
N
|
I2(%)
|
P
|
Pooled sensitivity (95% CI)
|
Pooled specificity (95% CI)
|
Pooled LR+ (95%CI)
|
Pooled LR- (95%CI)
|
DOR (95%CI)
|
High group | 4 | 27.5 | 0.25 | 0.853 (0.773 - 0.914) | 0.983 (0.960 - 0.994) | 34.910 (16.013 - 76.015) | 0.118 (0.009 - 1.596) | 302.47 (44.653 - 2048.9) |
Low group | 5 | 19.4 | 0.29 | 0.612 (0.534 - 0.658) | 1.000 (0.999 - 1.000) | 554.64 (91.139 - 3375.4) | 0.378 (0.166 - 0.862) | 2428.5 (795.47 - 7413.9) |
Others | 6 | 61.1 | 0.0249 | 0.970 (0.945 - 0.986) | 0.985 (0.978 - 0.990) | 53.316 (21.532 - 132.013) | 0.053 (0.011- 0.260) | 1438.9 (300.50 - 6890.40) |
c. Subgroup analysis of area of DBS and diagnostic accuracy
| ||||||||
Diameter
|
N
|
I2(%)
|
P
|
Pooled sensitivity (95% CI)
|
Pooled specificity (95% CI)
|
Pooled LR+ (95%CI)
|
Pooled LR- (95%CI)
|
DOR (95%CI)
|
Large | 5 | 44.3 | 0.13 | 0.861 (0.792 - 0.914) | 0.999 (0.997 - 1.000) | 103.91 (18.832 - 573.350) | 0.116 (0.038 - 0.729) | 1041.8 (151.62 - 7159.1) |
Small | 5 | 41.0 | 0.15 | 0.632 (0.557 - 0.702) | 1.000 (0.999 - 1.000) | 260.02 (40.310 - 1677.3) | 0.295 (0.122 - 0.711) | 1656.0 (421.89 - 6499.8) |
Others | 5 | 64 | 0.01 | 0.945 (0.918 - 0.965) | 0.983 (0.974 - 0.989) | 43.831 (19.745 - 97.298) | 0.043 (0.007 - 0.280) | 1085.71 (229.94 - 5126.46) |
Possible sources of heterogeneity of meta -analysis
| ||||
---|---|---|---|---|
study characteristic
|
Coefficient
|
P value
|
Relative DOR
|
95% CI
|
LOD | 0.33 | 0.5304 | 1.39 | 0.45 - 4.34 |
Area | -0.14 | 0.7802 | 0.87 | 0.28 - 2.65 |
PCR (real-time PCR vs.nested-PCR vs. others) | -1.68 | 0.0082 | 0.19 | 0.06 - 0.58 |