## 3 Results and Discussion
### Individual vs. Population Predictor
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & \begin{tabular}{c} **Number of** \\ **Predictions** \\ \end{tabular} & \
\begin{tabular}{c} **RMSE** \\ **Individual** \\ **(mg/dL)** \\ \end{tabular} &
\begin{tabular}{c} **RMSE** \\ **Population** \\ **(mg/dL)** \\ \end{tabular} \\ \hline \multicolumn{4}{c}{**PH = 15 min**} \\ \hline \multirow{2}{*}{Meals} & \multirow{2}{*}{133,540} & 6.58 (0.96) & 7.58 (1.20) \\  & & 6.54 [6.10, 6.79] & 6.98 [6.84, 7.99]\(\bullet\) \\ \hline \multirow{2}{*}{Night} & \multirow{2}{*}{26,426} & 4.90 (0.87) & 4.86 (0.87) \\  & & 4.71 [4.29, 5.07] & 4.57 [4.39, 4.87] \\ \hline \multirow{2}{*}{Hypo} & \multirow{2}{*}{4308} & 8.08 (2.97) & 8.67 (1.41) \\  & & 6.57 [6.43, 10.80] & 8.79 [7.63, 9.93] \\ \hline \multirow{2}{*}{Overall} & \multirow{2}{*}{164,274} & 6.52 (2.24) & 7.04 (1.99) \\  & & 6.37 [5.07, 6.70] & 6.96 [4.87, 8.67]\(\bullet\) \\ \hline \multicolumn{4}{c}{**PH = 30 min**} \\ \hline \multirow{2}{*}{Meals} & \multirow{2}{*}{128,144} & 12.08 (1.81) & 13.91 (2.31) \\  & & 11.71 [11.16, 12.33] & 12.68 [12.40, 15.19]\(\bullet\) \\ \hline \multirow{2}{*}{Night} & \multirow{2}{*}{24,659} & 7.93 (1.83) & 7.86 (1.82) \\  & & 7.42 [6.69, 8.35] & 7.19 [6.66, 7.96] \\ \hline \multirow{2}{*}{Hypo} & \multirow{2}{*}{3746} & 13.95 (4.67) & 14.13 (2.80) \\  & & 12.66 [11.30, 14.53] & 14.08 [12.51, 15.91] \\ \hline \multirow{2}{*}{Overall} & \multirow{2}{*}{156,549} & 11.32 (3.92) & 11.97 (3.72) \\  & & 11.27 [8.35, 12.65] & 12.49 [7.96, 14.23]\(\bullet\) \\ \hline \multicolumn{4}{c}{**PH = 60 min**} \\ \hline \multirow{2}{*}{Meals} & \multirow{2}{*}{117,356} & 19.49 (3.52) & 22.75 (4.28) \\  & & 18.58 [17.43, 20.09] & 20.29 [19.89, 25.56]\(\bullet\) \\ \hline \multirow{2}{*}{Night} & \multirow{2}{*}{21,142} & 10.46 (2.95) & 10.44 (3.02) \\  & & 9.67 [8.23, 11.08] & 9.45 [8.51, 10.62] \\ \hline \multirow{2}{*}{Hypo} & \multirow{2}{*}{2709} & 23.60 (9.77) & 24.10 (7.41) \\  & & 20.94 [17.57, 23.39] & 21.35 [18.81, 30.87] \\ \hline \multirow{2}{*}{Overall} & \multirow{2}{*}{141,207} & 17.85 (8.21) & 19.10 (8.04) \\  & & 17.44 [11.08, 20.93] & 19.52 [10.62, 23.37] \\ \hline \multicolumn{4}{c}{**PH = 120 min**} \\ \hline \multirow{2}{*}{Meals} & \multirow{2}{*}{95,780} & 26.80 (6.03) & 30.75 (5.86) \\  & & 24.77 [22.77, 28.19] & 29.63 [26.87, 31.95]\(\bullet\) \\ \hline \multirow{2}{*}{Night} & \multirow{2}{*}{14,149} & 12.01 (3.62) & 12.59 (4.50) \\  & & 11.24 [8.71, 14.29] & 11.58 [9.61, 12.96] \\ \hline \multirow{2}{*}{Hypo} & \multirow{2}{*}{1143} & 36.64 (21.12) & 40.45 (13.64) \\  & & 29.97 [20.72, 42.83] & 36.30 [30.22, 42.10] \\ \hline \multirow{2}{*}{Overall} & \multirow{2}{*}{111,072} & 25.15 (16.12) & 27.93 (14.58) \\  & & 22.72 [14.29, 28.19] & 28.79 [12.96, 34.57]\(\bullet\) \\ \hline \end{tabular}
\end{table} 
Table 2: Accuracy metrics of the individual and population glucose predictors for the 16-weeks validation dataset. Results show a small increase in the mean error in the population approach when compared to the individual one in the case of small _PHs_. However, in the worst case scenario, an increase of 4.86 mg/dL is detected when considering the Meals and Night glucose predictors, but this value can not be considered relevant in a medical context. On the other hand, this loss of prediction capability becomes clearer when considering longer _PH_ hypoglycemia predictors, where the RMSE increases to 6.89 mg/dL (\(PH=180\) min) and 13.68 mg/dL (\(PH=240\) min). It must be noted that this difference has not been found statistically significant. However, considering that the population predictors were trained with data from a population and not from data of the very same patient, the prediction errors are remarkably low, especially when considered in a clinical environment. The overall predictor being able to accurately predict glucose 4h (\(PH=240\) min) into the future with a RMSE of 30.40 mg/dL is very promising, especially when the individual predictor only yields errors of 27.28 mg/dL, a difference of 3.12 mg/dL, which is not statistically significant.