This research aims to propose a new vision to examine an analytical method during its life cycle, in order to show its performance and capability to guarantee good results for future analysis at a confidence level accepted. In this context, A method was proposed for separate and quantify simultaneously of five vitamins, that is ascorbic acid (vitamin C: VC), Thiamine hydrochloride (vitamin B1: VB1), Riboflavin (vitamin B2: VB2), Nicotinamide (vitamin B3: VB3) and Pyridoxine hydrochloride (vitamin B6: VB6) in tablet multivitamin. Chemometric tools, namely screening design factors (Plackett-Burman) and response surface methodology (Box-Behnken) were used to optimize the operating conditions of the liquid chromatography method chosen at the selection stage. The performances of the developed method were highlighted by applying of the approach based on the concept of the total error and accuracy profile. Results of accuracy profile showed that the 95%-expectation tolerance limits for all vitamins fell well within the acceptance limits at±10%. Therefore, chromatography method was capable of providing accurate results in the concentrations range studied of each vitamin. On the other hand, measurement uncertainty was calculated at each concentration level for each vitamin from validation data which these relative values did not exceed 5%. Finally, according to its life cycle, we can say that our method is apparent suitable for quality control the finished products contain water-soluble vitamins.