A method for alerting a user with a diabetes management device that the user's blood glucose data around a meal has exceeded a predefined value (Δ), the method comprising: collecting, with the diabetes management device , a number of pre- and post-prandial (N) pairs of glucose concentration measurements around a particular meal； calculate, with a microprocessor of the diabetes management device, a plurality of differential values (D) based on a difference between each pair of the plurality collected from pre- and post-prandial glucose concentration pairs around a particular meal； determine a fixed level value of significance (α) and a fixed statistical power value (1-β)； determine, with the microprocessor, where the number of plurality of pre- and post-prandial couples (N) is equal to or greater than a calculated sample size (m)； establish with at least one statistical test if the threshold value (Δ) has been exceeded with an acceptable level of safety； and after establishing that the threshold value (Δ) has been exceeded with an acceptable level of safety, generate to the user that for the particular meal, the plurality of differential values D for the number of pairs of glucose measurements has exceeded the value threshold (Δ), where the effect of α and β on the sample size (m) is implemented in the form of a constant K defined as: where z values correspond to a Normal variable of statistical tables depending on the predefined level of significance ( α) and of the statistical power (1-β), where the sample size m is calculated with an equation of the form: where s is a standard deviation of pre- and post-prandial measurements and Δ is the predefined threshold value ( Δ).Un método para alertar a un usuario con un dispositivo de gestión de diabetes de que los datos de glucosa en sangre del usuario alrededor de una comida han excedido un valor predefinido (&Delta；), comprendiendo el método: recoger, con el dispositivo de gestión de diabetes, un número de parejas (N) p
