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¶ … Suitable P-Value for a Clinical Trial
Statistical testing to determine whether results are significant is extremely useful in all types of research. In most cases, where a significant level, or p-value, is being chosen, a p-value of .05 is deemed to be sufficiently accurate. However, while this may be suitable for many types of research, it may be argued that in clinical trials from drugs, a lower p value may be more appropriate, due to the nature of the research. To understand this, it is necessary to understand what the p-value is, what it signifies.
The p value gives a probability, but is easy to misunderstand, as it indicates the level of support for the null hypothesis, with the probability level used to determine whether to accept or reject the null hypothesis. The p-value provides the probability of gaining an effect at the same level if the null hypothesis is true (Cowen, 1997). For example, if undertaking a basic hypothesis that there are at least twenty sweets in a packet of M&M's, with a null hypothesis that there are not twenty sweets in a packet, and the p-value is 0.4, this would mean there is only a 4% chance of the null hypothesis being true in that...
However, in drug trials there is the potential for human costs as well as financial costs, and it is essential to ensure that drugs are effective at treating conditions are designed for, as well as assessing the potential of undesired side-effects. It was as a result of flawed research, and the way in which results were presented, that the drug Vioxx made it onto the market, and subsequently needed to be withdrawn, after finding detrimental side effects, with more than 23,000 people suffering from heart attacks (Berenson, 2006). This indicates a high potential human cost associated with drug trials. Therefore, the cut-off rate may vary depending upon the hypothesis being tested, but should be at least .01, so that the result is only deemed to be statistically significant if there is only a 1% or less chance of the proving the null hypothesis. For example, if a new drug is developed to treat cancer the difference the…
References
Berenson, A, (2006, May 31), Merck Admits a Data Error on Vioxx, The New York Times, retrieved 13 November 2015 from http://www.nytimes.com/2006/05/31/business/31drug.html?_r=0
Cowen, G. (1997). Statistical Data Analysis. Oxford: Oxford University Press.
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