The patients will be randomly allocated to one of the two groups based on a computer-generated random number table (url:stattrek.com/statistics/random-number-generator.aspx). Randomization sequence concealment will include opaque-sealed envelopes with alphabetic codes whose distribution will be in control of an independent analyst. The envelopes will be opened; patient's data-slip will be pasted on them, and will be sent back to the control analyst.