Table 2.
Risk of bias assessment in cohort studies
| Study | Outcome | Bias due to confounding | Bias in selection of participants into the study | Bias in classification of interventions | Bias due to deviations from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported result | Overall bias |
|---|---|---|---|---|---|---|---|---|---|
| Alderdice et al. 2005 [51] | NICU | S | C | L | L | NI | S | L | C |
| Respiratory outcomes | S | C | L | L | NI | M | L | C | |
| Bailit et al. 2010 [52] | NICU | S | S | L | L | NI | S | L | S |
| Sepsis | S | S | L | L | NI | M | L | S | |
| (M) Hysterectomy | S | S | L | L | NI | L | L | S | |
| Balchin et al. 2008 [53] | Respiratory outcomes | S | C | L | L | NI | M | L | C |
| Brookfield et al. 2017 [36] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Chiossi et al. 2013 [37] | NICU, Apgar score | S | S | L | L | NI | S | L | S |
| Death | S | S | L | L | NI | L | L | S | |
| Respiratory outcomes, sepsis | S | S | L | L | NI | M | L | S | |
| (M) Death, hysterectomy | S | S | L | L | NI | L | L | S | |
| (M) Bleeding | S | S | L | L | NI | S | L | S | |
| Clark et al. 2009 [54] | NICU | S | S | L | L | NI | S | L | S |
| Doan et al. 2014 [44] | NICU, Apgar Score, jaundice | S | S | L | L | NI | S | L | S |
| Death, hypoglycemia | S | S | L | L | NI | L | L | S | |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Farchi 2010 | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Finn et al. 2016 [55] | NICU | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Gawlik et al. 2015 [43] | NICU, Apgar score | S | S | L | L | NI | S | L | S |
| Graziosi et al. 1998 [56] | NICU, jaundice | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hansen et al. 2008 [57] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Many et al. 2006 [58] | Respiratory outcomes | S | C | L | L | NI | M | L | C |
| Matsuo et al. 2008 [59] | Respiratory outcomes | S | C | L | L | NI | M | L | C |
| McAlister et al. 2013 [45] | NICU | S | C | L | L | NI | S | L | C |
| Melamed et al. 2014 [60] | NICU, Apgar score, jaundice | S | S | L | L | NI | S | L | S |
| Death, hypoglycemia | S | S | L | L | NI | L | L | S | |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| (M) Hysterectomy | S | S | L | L | NI | L | L | S | |
| (M) bleeding | S | S | L | L | NI | S | L | S | |
| Morrison et al. 1995 [61] | Respiratory outcomes | S | C | L | L | NI | M | L | C |
| Nakashima et al. 2014 [41] | NICU, jaundice | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hypoglycemia, sepsis | S | S | L | L | NI | L | L | S | |
| Nir et al. 2012 [46] | NICU, Apgar score, jaundice | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hypoglycemia | S | S | L | L | NI | L | L | S | |
| Parikh et al. 2014 [62] | NICU | S | S | L | L | NI | S | L | S |
| Death | S | S | L | L | NI | L | L | S | |
| Resende 2015 | NICU | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hypoglycemia | S | S | L | L | NI | L | L | S | |
| Terada et al. 2014 [50] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Tita et al. 2009 [38] | NICU | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hypoglycemia, sepsis | S | S | L | L | NI | L | L | S | |
| Tracy et al. 2007 [63] | NICU | S | S | L | L | NI | S | L | S |
| Van d. Berg et al. 2001 [64] | NICU | S | C | L | L | NI | S | L | C |
| Respiratory outcomes | S | C | L | L | NI | M | L | C | |
| Vidic 2016 | NICU, Apgar score, jaundice | S | S | L | L | NI | S | L | S |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Hypoglycemia | S | S | L | L | NI | L | L | S | |
| Vilchez et al. 2014 [39] | NICU, Apgar score | S | S | L | L | NI | S | L | S |
| Vilchez et al. 2015 [40] | Death | S | S | L | L | NI | L | L | S |
| Wilmink et al. 2010 [65] | NICU, Apgar score, jaundice | S | S | L | L | NI | S | L | S |
| Death, hypoglycemia, sepsis | S | S | L | L | NI | L | L | S | |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Wilmink et al. 2012 [66] | NICU, Apgar score | S | S | L | L | NI | S | L | S |
| Death, hypoglycemia, sepsis | S | S | L | L | NI | L | L | S | |
| Respiratory outcomes | S | S | L | L | NI | M | L | S | |
| Yamazaki et al. 2003 [42] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Hypoglycemia | S | S | L | L | NI | L | L | S | |
| Zanardo et al. 2004, two publications [48, 49] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
| Zanardo et al. 2007 [67] | Respiratory outcomes | S | S | L | L | NI | M | L | S |
Risk of bias assessment according to ROBINS-I tool. The seven bias domains are individually assessed for each study. The evaluation options are: L Low; M Moderate; S Serious; C Critical; NI No Information. Respiratory outcomes include all respiratory outcomes measured. Outcomes were summarized according to their risk of bias assessment
(M): Maternal outcomes