Wennerholm 1995

Methods	A randomised controlled trial comparing recommended sugar reduction both between meals, and in main meals supported by a list of the sugar content of various food products; with no intervention.
Participants	Population: 20 adults: 14 students at the Dental Technical School and 6 patients at the Department of Cariology, Göteborg University, Sweden. Setting: Department of Cariology, Göteborg University. Age: Mean age of 30.3 years (SD = 12.5) for the test group and age mean of 27.4 years (SD = 9.4) for the control group. Inclusion criteria: a) Having more than 300,000 CFU S. mutans/ml saliva b) harbouring both S. mutans and S. sobrinus in saliva c) eating sugar frequently. Exclusion criteria: None.
Interventions	In the test group participants were asked to refrain from sugar‐containing foods between meals and to reduce sugar in main meals. Detailed information about sugar content of various food products was given to the participants at baseline. Control group: No advice. Duration: 6 weeks. Personnel conducting interventions: One of the authors.
Outcomes	Primary outcome: The number of sugar intakes per day (both in between meals and main meals). Breakfast, lunch and dinner were defined as main meals. Data were collected by means of a standardised questionnaire consisting of lists of 32 commonly used sugar‐containing products, recording the intake frequency of each product. Two or more products consumed on the same occasion were only scored as one intake. If a participant did not consume a sugar‐containing product every day, but at least three times a week, a score of 0.5 was given. The subjects were allowed to consume one piece of fruit per day, and this was given a score of 1. Time points measured: Baseline, 3, 6 and 12 weeks.
Notes	Sugar intake frequency per day at baseline = 9.5 (SD = 1.9) in the test group and 7.2 (SD = 2.6) in the control group. Analysis compares baseline and follow‐up rather than intervention and control.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	.."randomly divided" but no further details.
Allocation concealment (selection bias)	Unclear risk	Not reported.
Blinding (performance bias and detection bias) primary outcomes	Unclear risk	Not reported.
Blinding (performance bias and detection bias) secondary outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no withdrawals from the study.
Selective reporting (reporting bias)	Low risk	All expected outcomes reported.

BMI = body mass index; SD = standard deviation.