Table 2

Inclusion and exclusion criteria

Inclusion criteriaExclusion criteria
P≥18 years
High risk of diabetes: impaired glucose tolerance, impaired fasting glucose and/or borderline HbA1c (by any established criteria—subject to variation given the time-periods and geographical areas covered by the search), metabolic syndrome, overweight/obesity, presence of multiple cardiovascular risk factors and/or high diabetes-risk or cardiovascular-risk score outcome
n-number for each treatment arm of each primary study ≥25 for ≥75% of included studies
Review limited to study of populations with previous gestational diabetes
I≥75% of primary studies assess combined diet and physical activity intervention involving ≥2 interactions with a healthcare professional, and ≥75% of total review n-number received such an interventionDiet or physical activity intervention alone
No face-to-face or telephone contact with healthcare professional
CNo/usual care or lower intensity intervention (where relevant)Comparison with pharmacological or surgical intervention only
ODuration of follow-up ≥12 months for ≥75% of the number of studies and total number of participants
SSystematic review as per Centre for Reviews and Dissemination Database of Abstracts of Reviews of Effects criteria,19 plus clear statement of the clinical topic, description of evidence retrieval methods and sources, and inclusion of at least one study that met minimum methodological standards for inclusion
Reviews considering single group and/or comparative studies included
Review published post-1990
Review updated
Non-English language review