Lang 1989.

Methods	Study described as a randomised trial.
Participants	157 pregnant women, all were less than 38 weeks of gestation and had symptoms of dyspepsia during pregnancy of recent onset. Exclusion criteria were women who had signs or symptoms of pre‐eclampsia, with a history of dyspepsia or suspected peptic ulcer prior to pregnancy. Women had mild, moderate and severe degree of heartburn at study entry.
Interventions	Group 1: 10 mL of algicon suspension. (N = 79) Group 2: 10 mL of magnesium trisilicate mixture. (N = 78) Study duration: 2 weeks.
Outcomes	Relief of heartburn, symptoms incidence and severity and side effects.
Notes	High post‐randomisation attrition rates (38% lost to follow‐up by 2 weeks and therefore at high risk of bias, see below). Data on heartburn relief from this study were presented into different categories (daytime and night‐time ; at week 1 and week 2); therefore data were not included in the analysis. We did not attempt to contact the authors as the study was conducted several years ago (1989).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information on how randomisation was carried out.
Allocation concealment (selection bias)	Unclear risk	Not reported.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	High risk	38% lost to follow‐up by 2 weeks.
Selective reporting (reporting bias)	Low risk	Relevant data reported.
Other bias	Low risk	None noted.