Table 3.
Summary table of number of significant benefits and effect sizes achieved and length of intervention and follow-up period by type of behavioral intervention
| Type of intervention | Blood pressure monitoring | Nutrition only | Physical activity only | Multi-behavior change |
|---|---|---|---|---|
| Number of trials | 4 | 4 | 5 | 18 |
| Reported behavioral outcome | 1 | 3 | 3 | 13 |
| Significant behavior benefit (N) | 1 | 3 | 2 | 11 |
| Behavior change effect size from meta-analysis | 0.42 | 0.15 | 0.34 | 0.53 |
| Reported physiological outcome | 2 | 4 | 5 | 18 |
| Significant physiological benefit (N) | 1 | 3 | 4 | 18 |
| Physiological change effect size from meta-analysis | 0.09 | 0.03 | 0.34 | 0.48 |
| Reported weight outcome | 0 | 4 | 2 | 17 |
| Significant weight benefit (N) | N/A | 4 | 0 | 16 |
| Weight change effect size from meta-analysis | N/A | 0.14 | 0.08 | 0.74 |
| Reported morbidity | 1 | 4 | 1 | 8 |
| Significant morbidity benefit (N) | 0 | 3 | 1 | 4 |
| Reported mortality | 1 | 1 | 1 | 3 |
| Significant mortality benefit (N) | 0 | 0 | 0 | 0 |
| Range of duration of intensive intervention period (months) | 3–24 | 2.5–48 | 3–24 | 3–60 |
| Mode (most common) length (months) | 3 | 12–14 | 6–12 | 6–12 |
| Range of length of total follow-up (months) | 3–24 | 14–72 | 6–24 | 6–72 |
| Mode (most common) length (months) | 6 | 12–14 | 12 | 12 |
Tables in cells reflect sub-group analysis of the behavioral intervention trials by their specific focus of the intervention—blood pressure monitoring, nutrition only, physical activity only, multi-factor, or lifestyle interventions. The multi-factor interventions had to include at least two of the following behavior change targets—nutrition, physical activity, and smoking. We report the number of trials for each type of intervention and the number who reported and who found significant benefits for behavior, physiological, morbidity, or mortality outcomes. We also include the effect size that we calculated from the meta-analysis of effect sizes from each type of intervention. Effect sizes above are weighted by sample size. Please note that the effect sizes were quite different for the nutrition intervention trials for standard error versus weighted by sample size because of the large sample size of the WHI trial. For the nutrition only interventions, effect sizes for the behavioral outcome were 0.98 when weighted by standard error and 0.15 when weighted by sample size; for the physiological outcome were 0.28 when weighted by standard error and 0. 03 when weighted by sample size; and for the weight outcome were 0.35 when weighted by standard error and 0.14 when weighted by sample size