You are all just guessing. Better to do some research.
[I Googled "study appropriately powered" without the quotes.]
The concept of "power" has a special meaning when used in the context of clinical research. The "power" of a trial or study is a measurable, or calculable quantity.
(1) BMC (British Medical Council) Research Methodology
A tutorial on pilot studies: the what, why and how
http://www.biomedcentral.com/1471-2288/10/1
A study should only be conducted if the results will be informative; [...] The focus of a pilot study should be on assessment of feasibility, unless it was
powered appropriately to assess statistical significance.
(2) The Wikipedia article about clinical trials...
http://en.wikipedia.org/wiki/Clinical_trial#Statistical_power
Statistical power
The number of patients enrolled in a study has a large bearing on
the ability of the study to reliably detect the size of the effect of the study intervention. This is described as the "power" of the trial. The larger the sample size or number of participants in the trial, the greater the statistical power.
However, in designing a clinical trial, this consideration must be balanced with the fact that more patients make for a more expensive trial. The power of a trial is not a single, unique value; it estimates the ability of a trial to detect a difference of a particular size (or larger) between the treated (tested drug/device) and control (placebo or standard treatment) groups. By example, a trial of a lipid-lowering drug versus placebo with 100 patients in each group might have a power of 0.90 to detect a difference between patients receiving study drug and patients receiving placebo of 10 mg/dL or more, but only have a power of 0.70 to detect a difference of 5 mg/dL.
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