Table 6.
Perinatal outcome. Calculations are CTG+ST analysis vs. CTG alone
| Meta-analysis | Cochrane review Neilson (2012) | European MA Becker et al. (2012) | American MA Potti & Berghella (2012) | Stockholm MA Salmelin et al. (2013) | IPD MA Schuit et al. (2013) |
|---|---|---|---|---|---|
| Apgar score <7 at 5 min | 103/7678 vs. 108/7624 (1.34 vs. 1.42%) Fixed-effect (I2 0.0%, chi-square p = 0.44): RR 0.95 (0.73–1.24) | 103/7697 vs. 108/7641 (1.34 vs. 1.41%) Fixed-effect (Tau2 0, I2 0%): RR 0.95 (0.73–1.2) | 103/7678 vs. 108/7624 (1.34 vs. 1.42%) Unclear MA type: RR 0.95 (0.73–1.24) | MA not performed | 89/6524 vs. 78/6463 (1.36 vs. 1.21%) RR 1.14 (0.84–1.54) |
| Comments on Apgar score | – | Random-effect model yielded same results | Detailed RCT data not provided | – | – |
| Metabolic acidosis (pH <7.05 plus BDecf >12.0 mmol/L) | MA not performed | 50/7697 vs. 73/7641 (0.65 vs. 0.96%) Random-effect (Tau2 0.13, I2 33%): RR 0.72 (0.43–1.19) Fixed-effect: RR 0.68 (0.48-0.97) | 59/7318 vs. 81/7256 (0.81 vs. 1.12%) Random-effect (Tau2 0.28, I2 62%, p = 0.03): RR 0.80 (0.44–1.47) | 51/6459 vs. 61/6409 (0.79 vs. 0.95%) Random-effect (Tau2 0.28, I2 63%, chi-square p = 0.04): RR 0.96 (0.49–1.88) | 57/6524 vs. 73/6463 (0.87 vs. 1.13%) (Tau2 0.09, I2 42%): RR 0.76 (0.53–1.10) |
| Comments metabolic acidosis BDecf analysis | – | Finnish RCT BDecf data obtained via principal investigator, yet incorrect data in MA; incorrect data from Swedish RCT used | Original, not revised Swedish RCT data included; Finnish RCT metabolic acidosis from BDblood data, not BDecf | Incorrect data from Swedish RCT used; Finnish RCT metabolic acidosis from BDblood data, not BDecf | Additional cases in comparison with original or revised articles: Swedish +1, French +6; error in addition of cases |
| Metabolic acidosis (pH <7.05 plus BDblood >12.0 mmol/L) | 78/7318 vs. 113/7259 (1.06 vs. 1.56%) Random-effect (Tau2 0.24, I2 62%): RR 0.78 (0.44–1.37) | MA not performed | MA not performed | MA not performed | RR 0.82 (0.58–1.16) |
| Comments metabolic acidosis BDblood analysis | MA is a mixture of BDblood metabolic acidosis (Finnish, Dutch RCTs) and BDecf metabolic acidosis (Plymouth, Swedish, French RCTs) | – | – | – | Detailed IPD cannot be checked; Swedish and French RCTs excluded for unclear reasons |
| Cord artery pH <7.15 | MA not performed | MA not performed | MA not performed | MA not performed | RR 0.99 (0.91–1.08) |
| Comments cord artery pH <7.15 | – | – | – | – | Detailed IPD cannot be checked |
| Cord artery pH <7.05 | MA not performed | Included 5 RCTs, detailed data not provided Random-effects (statistics not provided): RR 0.97 (0.64–1.5) | MA not performed | MA not performed | RR 0.87 (0.70–1.09) |
| Comments cord artery pH <7.05 | – | Data not reported in original or revised Swedish RCT, unclear how Swedish data were retrieved | – | – | Detailed IPD cannot be checked |
| Cord artery pH <7.00 | MA not performed | MA not performed | MA not performed | MA not performed | RR 0.89 (0.62–1.26) |
| Comments on cord artery pH <7.00 | – | – | – | – | Detailed IPD cannot be checked; error in addition of cases |
| Cord artery BDecf >12.0 mmol/L | MA not performed | MA not performed | MA not performed | MA not performed | RR 1.07 (0.90–1.29) |
| Comments on cord artery BDecf >12.0 mmol/L | – | – | – | – | Detailed IPD cannot be checked; error in addition of cases; low quality of French RCT data [see 6] |
| Cord artery BDblood >12.0 mmol/L | MA not performed | MA not performed | MA not performed | MA not performed | RR 0.98 (0.82–1.16) |
| Comments on cord artery BDblood >12.0 mmol/L | – | – | – | – | Detailed IPD cannot be checked; error in addition of cases |
| Admission neonatal intensive care unit | 615/7678 vs. 685/7624 (8.00 vs. 8.98%) Fixed-effect (I2 0.0%, chi-square p = 0.97): RR 0.89 (0.81–0.99) | Included 5 RCTs, detailed data not provided Random-effect (statistics not provided): RR 0.90 (0.76–1.1) | 264/7678 vs. 289/7624 (3.44 vs. 3.79%) Unknown MA type: RR 0.90 (0.76–1.06) | MA not performed | RR 0.92 (0.76–1.09) |
| Comments neonatal intensive care unit admission | – | Fixed-effect model yielded same results | Error in numbers of index cases, cannot be checked due to lack of detailed information in MA article | – | Detailed IPD cannot be checked; fewer cases included from Finnish and French RCTs than in original articles |
| Neonatal encephalopathy | 8/7678 vs. 15/7624 (0.10 vs. 0.20%) Fixed-effect (I2 0%, chi-square p = 0.51): RR 0.54 (0.24–1.25) | Sarnat & Sarnat grade ≥2 data only: included 3 RCTs, detailed data not provided Random-effect (statistics not provided): RR 0.66 (0.19–2.3) | 8/7678 vs. 15/7624 (0.10 vs. 0.20%) Fixed-effect (I2 0%, chi-square p = 0.51): RR 0.54 (0.24–1.25) | 7/6478 vs. 11/6426 (0.11 vs. 0.17%) Random-effect (statistics not provided): RR 0.63 (0.24–1.63) | RR 0.42 (0.11–1.64) |
| Comments neonatal encephalopathy | No uniform definition of encephalopathy in RCTs; no data in Plymouth RCT – data in MA provided by RCT authors | Fixed-effects model yielded same results; 3 RCTs included but Sarnat & Sarnat stage ≥2 data reported only in Swedish and Dutch RCTs | No uniform definition of encephalopathy in RCTs; no data in Plymouth RCT – unclear how Plymouth data were obtained | No uniform definition of encephalopathy in RCTs; figures for Sarnat & Sarnat stage ≥1 from Swedish RCT used but ≥2 from Dutch RCT | Detailed IPD cannot be checked; numbers fewer than in original RCT articles, reported hypoxic-ischemic encephalopathy |
| Neonatal intubation | 7/714 vs. 9/722 (0.98 vs. 1.24%) | MA not performed because only 1 RCT | MA not performed | MA not performed | RR 0.64 (0.35–1.20) |
| Comments on neonatal intubation | Data available only from Finnish RCT | – | – | – | Detailed IPD cannot be checked; data from French and Dutch RCTs supplemented; incorrect data from Finnish RCT |
| Perinatal death | 8/7697 vs. 5/7641 (0.10 vs. 0.065%) Fixed-effect (I2 0.0%, chi-square p = 0.69): RR 1.49 (0.53–4.18) | Included 3 RCTs, detailed data not provided Random-effect (statistics not provided): RR 1.17 (0.38–3.6) | 8/7697 vs. 5/7641 (0.10 vs. 0.065%) Fixed-effect (I2 0%, chi-square p = 0.69): RR 1.49 (0.53–4.18) | MA not performed | RR 1.24 (0.33–4.61) |
| Comments on perinatal death | No data on perinatal death in Plymouth RCT – data in MA provided by RCT authors | Fixed-effects model yielded same results; data from 4 RCTs available, Finnish RCT data inexplicably excluded; unclear if data were corrected for lethal malformations | Perinatal death data included from 5 RCTs, but no data on how perinatal mortality data in the Plymouth RCT were obtained | – | Swedish RCT represented by mortality corrected for lethal malformations, but Dutch RCT by uncorrected mortality |