Related Experiment Video
Updated: Mar 19, 2026

Problem-Solving Before Instruction PS-I: A Protocol for Assessment and Intervention in Students with Different Abilities
Published on: September 11, 2021
Calculations to determine sample size
Abstract:
Evidence-based care is currently being promoted in the NHS. The implications of this strategy are that nursing practice should be based on evidence rather than opinion or tradition. It is generally accepted that the strongest evidence is provided by a randomised controlled trial. In a randomised controlled trial two groups are involved, one of which receives a new treatment and one of which, the control group, receives a standard or alternative treatment. Ideally, tables of random numbers are used to allocate individual patients to the new treatment and the alternative treatment. In this context, treatment may include not only medication but also an educational or other therapeutic intervention. 'The method is thus widely applicable to nursing research.
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