Study Author |
Study Design |
Study Population |
Exclusion
Criteria |
Outcome with Definition and Method of Measurement |
Candidate
Predictors, n |
Participants, n (events) |
Events per Variable |
Modelling Method |
Predictors in Final Model, n
|
Calibration |
Discrimination |
Validation |
Presentation of final prediction model or
tool |
Primary author nterpretation of presented model |
Ahmadzia et al., 201814
|
Retrospective Cohort
|
Patients who underwent caesarean section delivery
|
Vaginal delivery and incomplete data for intrapartum and postpartum
blood transfusion
|
Intraoperative and postoperative blood transfusion
|
Model 1: 16
Model 2: 23
|
56, 967 (1488)
|
Model 1: 93
Model 2: 64.7
|
Logistic
|
14
|
Association between predicted probability of transfusion and observed
incidence in deciles of the risk score distribution’ Calibration graph
provided.
|
Model 1: AUC 0.77 (95% CI 0.75-0.78)
Model 2: AUC 0.83 (95% CI 0.81-0.84)
|
Internal validation by random split of data
|
Online Risk Calculator
|
Confirmatory
|
Baba et al., 2014
15
|
Retrospective Cohort
|
All women with placenta praevia who underwent a caesarean section
|
None
|
Blood Transfusion: haemoglobin <6.0g/dL or systolic BP
<70mmHg or estimated blood loss reached
>2500ml
|
9
|
205 (20)
|
2.22
|
Logistic
|
5
|
None
|
AUC 0.844 (95% CI 0.731-0.958)
|
None
|
Equation
|
Exploratory
|
Biguzzi et al., 2011
16
|
Unclear
|
All women who underwent vaginal delivery
|
Age <18 years, Caesarean section, Delivery before the 37th
week of gestation, Twin pregnancy, No comprehension of the Italian
language, Refusal to sign a written informed consent. Deliveries that
occurred on Friday afternoon
|
Postpartum haemorrhage (blood loss of ≥500ml) measured by visual
estimation using graduated basin
|
16
|
6011 (1435)
|
89.69
|
Logistic
|
5
|
Graph plotting predicted probabilities against observed outcomes –
inadequate information on how curve was developed
|
AUC 0.70
|
Internal Validation with bootstrap sampling
|
Nomogram
|
Exploratory
|
Chi et al., 2016
17
|
Retrospective
Case-control
|
Parturient patients with complete prenatal examination data
|
None
|
Postpartum haemorrhage
|
21
|
923 (447)
|
21.29
|
Logistic
|
15
|
None
|
None
|
None
|
Score assigned
|
Exploratory
|
Dunkerton et al., 2018
18
|
Retrospective cohort
|
All caesareans at a single university hospital trust in U. K
|
None
|
Postpartum haemorrhage (estimated blood loss of ≥ 1000ml, annual staff
training with pictorial reference cards)
|
17
|
24,230 (2997)
|
176.29
|
Hothorn et al’s non-parametric recursive partitioning algorithm
|
9
|
None
|
None
|
Internal validation by data splitting
|
Decision tree
|
Confirmatory
|
Kim et al., 2017
19
|
Registry data
|
Patients with placenta praevia who underwent caesarean section
|
Coagulopathie-s and incomplete data
|
Massive transfusion (transfusion of ≥8 units pRBC within 24h after
delivery)
|
12
|
238 (31)
|
2.58
|
Logistic
|
5
|
Hosmer-Lemeshow test (p=0.44)
|
Internal validationAUC (0.84)
External validation AUC (0.88)
|
Internal validation by bootstrapping and External Validation of score
model
|
Scoring system
|
Confirmatory
|
Lee et al., 2018
20
|
Retrospective Cohort
|
Pregnant women with placenta praevia
|
Multiple pregnancies, Maternal obstetrical or medical problems other
than placenta praevia and Fetal anomalies
|
Massive haemorrhage defined as blood loss ≥ 2000ml during surgery,
postpartum transfusion of four or more pints of packed red blood cells,
caesarean hysterectomy or uterine arterial embolization triggered by
post-partum bleeding.
|
16
|
560 (73)
|
4.56
|
Logistic
|
7
|
None
|
AUC (0.856)
|
None
|
Sum score
|
Confirmatory
|
Prata et al., 2011
21
|
Prospective Cohort
|
Women anticipating a singleton vaginal delivery of gestational age
>36 weeks
|
Delivery by caesarean section, missing information on delivery
type
|
Postpartum haemorrhage defined as blood loss greater than 500ml during
the first 4 hours after delivery (measured by calibrated drapes)
|
20
|
2510 (93)
|
4.65
|
Logistic
|
8
|
None
|
None
|
None
|
Cumulative scores: number of risk factors vs risk
|
Exploratory
|
Rubio-Alvarez et al., 2018
22
|
Retrospective cohort
|
Women with singleton pregnancies who had vaginal birth
|
Antenatal fetal demise, Multiple pregnancies and Gestations
<35 weeks
|
Excessive postpartum blood loss defined as a reduction in haemoglobin
(Hb)levels greater than 3.5g/dL and a final Hb <8g/dL between
onset of birth and 24 hours after it
|
14
|
2336 (43)
|
3.07
|
Logistic
|
6
|
Hosmer-Lemeshow test (no result reported)
|
AUC 0.9 (0.85-0.93)
|
Internal Validation by random-split of data
External validation (temporal) AUC of 0.83 (0.74-0.92)
|
Risk Tool for Excel
|
Confirmatory
|
Tsu 1994
23
|
Case-control
|
Women with singleton vertex deliveries and spontaneous onset of
labour
|
None
|
Postpartum blood loss of at least 600ml after a normal, unassisted
vaginal delivery
|
5
|
653 (151)
|
30.2
|
Logistic
|
5
|
None
|
only ROC no AUC
|
None
|
Equation
|
Exploratory
|
Yoon et al., 2014
24
|
Prospective Cohort
|
Singleton pregnancy women with placenta praevia delivered by caesarean
section
|
None
|
Occurrence of peripartum complications: Perioperative blood transfusion
(determined by attending anaesthesiologist during CS when clinical
evidence of inadequate oxygen-carrying capacity or ongoing profuse blood
loss) or uterine artery embolization (to control moderate uterine
bleeding immediately after CS when vital status of the patient was
stable) or caesarean hysterectomy (vital status of patient was unstable
despite vigorous massive transfusion and haemostatic manoeuvres)
|
12
|
110 (38)
|
2.89
|
Logistic
|
6
|
None
|
None
|
None
|
Scoring model
|
Exploratory
|