New Zealand 1985.

Methods	'Randomised into two groups'; no further information was given. No losses to follow‐up were reported.
Participants	100 women at 28 weeks' gestation without pre‐existing diabetes were given a 100 g non‐fasting OGTT. NDDG 1979 criteria were used to diagnose GDM. Settings: prenatal clinics, National Women's Hospital, Mexico.
Interventions	Experimental: 52 women; 100 g glucose polymer screening test was given before a 100 g OGTT glucose polymer tolerance test was given. Control: 48 women; 100 g glucose screening test was given before a 100 g GTT was given.
Outcomes	Women: 1‐, 2‐ and 3‐hour blood glucose at GTT. Babies: gestation at birth, mean birthweight.
Notes	Mean birthweight was reported: 3427 g (SD 566) for polymer screening group vs 3280 g (SD 739) for glucose screening group. Report includes a case series of a further 178 women not included in this review who received a 100 g glucose polymer screening test followed by a 100 g GTT using glucose polymer. Study dates: not reported. Funding sources: not reported; declarations of interest: not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	'Randomised'; no further information was reported.
Allocation concealment (selection bias)	Unclear risk	Concealment of allocation was not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No women were lost to follow‐up.
Selective reporting (reporting bias)	Low risk	Specified outcomes have been reported.
Other bias	Low risk	No significant group differences in baseline characteristics were noted.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding of personnel and participants was not reported but was possible because the tests consisted of glucose drinks and could have appeared to be identical outcomes of plasma glucose value and of birthweight would not have been affected by knowledge of treatment groups.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding of outcome assessors was not stated. Outcomes of plasma glucose value and birthweight would not have been affected by knowledge of treatment groups.