Effectiveness of interventions to promote physical activity among socioeconomically disadvantaged women : a systematic review and meta-analysis

Physical activity is important for preventing weight gain and obesity, but women experiencing socioeconomic disadvantage are at high risk of inactivity. This study aimed to determine the effectiveness of interventions to increase physical activity among women experiencing disadvantage, and the intervention factors (i.e. physical activity measure, delivery mode, delivery channel, setting, duration, use of theory, behavioural techniques, participant age, risk of bias) associated with effectiveness. We conducted a meta-analysis of controlled trials using random-effects models and meta-regression. Seven databases were searched for trials among healthy women (18&ndash;64 years), which included a physical activity intervention, any control group, and statistical analyses of a physical activity outcome at baseline and post-intervention. Nineteen studies were included (n&thinsp;=&thinsp;6,339). Because of substantial statistical heterogeneity (&chi;2&thinsp;=&thinsp;53.61, df&thinsp;=&thinsp;18, P&thinsp;&lt;&thinsp;0.0001, I2&thinsp;=&thinsp;66%), an overall pooled effect is not reported. In subgroup analyses, between-group differences were evident for delivery mode, which modestly reduced heterogeneity (to 54%). Studies with a group delivery component had a standardized mean difference of 0.38 greater than either individual or community-based delivery. Programs with a group delivery mode significantly increase physical activity among women experiencing disadvantage, and group delivery should be considered an essential element of physical activity promotion programs targeting this population group.<br /

Dietary advice for the prevention of type 2 diabetes mellitus in adults.

Background: Prevention of type 2 diabetes in adults is a far better option than treatment, to alleviate pressure on health care providers and resources. However, there is no current review of the evidence regarding the efficacy of a diet-only intervention for prevention. Objectives: To assess the effects of type and frequency of dietary advice for the prevention of type 2 diabetes mellitus. Search methods: We carried out a comprehensive search of The Cochrane Library, MEDLINE, EMBASE, CINAHL, AMED, bibliographies and contacted relevant experts. Selection criteria: All randomised controlled trials, of twelve months or longer, in which dietary advice for the prevention of type 2 diabetes was the only intervention in adults. Data collection and analysis: The lead investigator performed all data extraction and quality scoring with duplication being carried out by one of the other four investigators independently with discrepancies resolved by discussion and consensus. Authors were contacted for missing data. Change data are presented. Main results: Two trials which randomised 358 people to dietary treatment and control groups were identified. Longest duration of follow-up was six years. In the 6-year Da Qing IGT & Diabetes study, the incidence of type 2 diabetes in the control group was 67.7% (95% confidence interval (CI) 59.8% to 75.2%) which was reduced to 43.8% (95% CI 35.5% to 54.7%) in the diet group. Overall, the dietary intervention group had a 33% reduction in the incidence of diabetes after six years (P < 0.03). The Oslo Diet & Exercise Study (ODES) found significant (P<0.05) reductions in insulin resistance, fasting insulin (pmol/L), fasting C-peptide (pmol/L), fasting proinsulin (pmol/L), fasting blood glucose (mmol/L), BMI (kg/m²), mBP (mmHg) and fasting triglycerides (mmol/L), and a significant increase in fasting HDL cholesterol (mmol/L) and PAI-1 (U/ml) after 12 months of dietary intervention. Data on mortality, morbidity, health-related quality of life, adverse effects, costs were not reported in either study