Inclusion and exclusion criteria
| Inclusion criteria | Exclusion 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 intervention | Diet or physical activity intervention alone |
| No face-to-face or telephone contact with healthcare professional | ||
| C | No/usual care or lower intensity intervention (where relevant) | Comparison with pharmacological or surgical intervention only |
| O | Duration of follow-up ≥12 months for ≥75% of the number of studies and total number of participants | |
| S | Systematic 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 |