| Study characteristics |
| Patient Sampling |
Diamniotic twin pregnancies with 2 live births from tertiary care centre |
| Patient characteristics and setting |
503 diamniotic twin pregnancies (1 April 1994 to 11 January 2002); GA: growth discordant twins: mean 34.4 (SD 2.9) weeks, growth concordant twins: mean 35.6 (SD 2.9) weeks; tertiary care centre |
| Index tests |
EFW and AC |
| Target condition and reference standard(s) |
Birth weight discordance |
| Flow and timing |
Excluded women with chromosomal and structural anomalies, pregnancies complicated by TTTS and intrauterine death of 1 or both fetuses |
| Comparative |
|
| Notes |
|
| Methodological quality |
| Item |
Authors' judgement |
Risk of bias |
Applicability concerns |
| DOMAIN 1: Patient Selection |
| Was a consecutive or random sample of patients enrolled? |
Yes |
|
|
| Was a case‐control design avoided? |
Yes |
|
|
| Did the study avoid inappropriate exclusions? |
Yes |
|
|
| Could the selection of patients have introduced bias? |
|
Low risk |
|
| Are there concerns that the included patients and setting do not match the review question? |
|
|
Low concern |
| DOMAIN 2: Index Test (All tests) |
| Were the index test results interpreted without knowledge of the results of the reference standard? |
Unclear |
|
|
| If a threshold was used, was it pre‐specified? |
Yes |
|
|
| Could the conduct or interpretation of the index test have introduced bias? |
|
Unclear risk |
|
| Are there concerns that the index test, its conduct, or interpretation differ from the review question? |
|
|
Low concern |
| DOMAIN 3: Reference Standard |
| Is the reference standards likely to correctly classify the target condition? |
Unclear |
|
|
| Were the reference standard results interpreted without knowledge of the results of the index tests? |
Unclear |
|
|
| Could the reference standard, its conduct, or its interpretation have introduced bias? |
|
Unclear risk |
|
| Are there concerns that the target condition as defined by the reference standard does not match the question? |
|
|
Low concern |
| DOMAIN 4: Flow and Timing |
| Was there an appropriate interval between index test and reference standard? |
Unclear |
|
|
| Did all patients receive the same reference standard? |
Yes |
|
|
| Were all patients included in the analysis? |
Unclear |
|
|
| Could the patient flow have introduced bias? |
|
Unclear risk |
|
