A medical system for monitoring a patient, said system comprising: one or more processors programmed to: receive patient data for the patient, the patient data including vital sign measurements and laboratory results; calculate a vital signs instability index regarding a physiological condition of the patient from the received vital sign measurements; calculate a laboratory instability index regarding the physiological condition from the received laboratory results; and integrate the VIX and the LIX into an indicator of patient deterioration, wherein the integration includes: looking up a prevalence value in a VIX-to-prevalence table using the VIX and the LIX, the prevalence value indicating a prevalence of unstable VIX segments in a training population for differing VIX ranges and LIX bands, the VIX ranges spanning the range of possible values for the VIX in predetermined increments, the LIX bands representing differing degrees of risk with the physiological condition and including the range of possible values for the LIX, wherein the VIX segments of the training population correspond to VIX trends over a predetermined period of time; and mapping the prevalence value to a value of the indicator by linearly adjusting the prevalence value so it scales over the range of prevalence values in the VIX-to-prevalence table. one or more processors programmed to: receive patient data for the patient, the patient data including vital sign measurements and laboratory results; calculate a vital signs instability index regarding a physiological condition of the patient from the received vital sign measurements; calculate a laboratory instability index regarding the physiological condition from the received laboratory results; and integrate the VIX and the LIX into an indicator of patient deterioration, receive patient data for the patient, the patient data including vital sign measurements and laboratory results; calculate a vital signs instability index regarding a physiological condition of the patient from the received vital sign measurements; calculate a laboratory instability index regarding the physiological condition from the received laboratory results; and integrate the VIX and the LIX into an indicator of patient deterioration, wherein the integration includes: looking up a prevalence value in a VIX-to-prevalence table using the VIX and the LIX, the prevalence value indicating a prevalence of unstable VIX segments in a training population for differing VIX ranges and LIX bands, the VIX ranges spanning the range of possible values for the VIX in predetermined increments, the LIX bands representing differing degrees of risk with the physiological condition and including the range of possible values for the LIX, wherein the VIX segments of the training population correspond to VIX trends over a predetermined period of time; and mapping the prevalence value to a value of the indicator by linearly adjusting the prevalence value so it scales over the range of prevalence values in the VIX-to-prevalence table. looking up a prevalence value in a VIX-to-prevalence table using the VIX and the LIX, the prevalence value indicating a prevalence of unstable VIX segments in a training population for differing VIX ranges and LIX bands, the VIX ranges spanning the range of possible values for the VIX in predetermined increments, the LIX bands representing differing degrees of risk with the physiological condition and including the range of possible values for the LIX, wherein the VIX segments of the training population correspond to VIX trends over a predetermined period of time; and mapping the prevalence value to a value of the indicator by linearly adjusting the prevalence value so it scales over the range of prevalence values in the VIX-to-prevalence table.