Final answer:
A grade 'A' recommendation on the USPSTF evidence pyramid includes meta-analyses or systematic reviews of randomized controlled trials and randomized controlled trials. These are considered high-quality evidence due to their methodological rigor and systematic approach.
Step-by-step explanation:
The question relates to the level of evidence required for a grade 'A' recommendation on the United States Preventive Services Task Force (USPSTF) evidence pyramid. A grade 'A' recommendation is based on high-quality evidence, indicating that the USPSTF recommends the service and finds a high certainty that the net benefit is substantial. The studies included in a grade 'A' recommendation are:
- Meta-analyses or systematic reviews of randomized controlled trials
- Randomized controlled trials
These types of studies provide strong evidence due to the systematic approach and control over variables, which is indicated by the reference example given:
Speck, R. M., Courneya, K. S., Masse, L. C., Duval, S., & Schmitz, K. H. (2010). An update of controlled physical activity trials in cancer survivors: A systematic review and meta-analysis.
Journal of Cancer Survivorship
, 4, 87-100.
This example is a systematic review and meta-analysis of controlled trials, which fits the criteria for grade 'A' evidence, as it collates and synthesizes multiple randomized controlled trials relating to physical activity in cancer survivors.