Patent ID: 8657746

Claim:
A method comprising: obtaining a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient; determining, via a controller and based at least partly on the series of samples, at least one metric to characterize one or more non-physiological anomalies of a representation of the blood glucose level of the patient by the at least one sensor signal, wherein said determining at least one metric comprises: ascertaining a residual portion of the at least one sensor signal based at least in part on the series of samples of the at least one sensor signal; and determining at least one value associated with the residual portion of the at least one sensor signal; ascertaining one or more principal components of the at least one sensor signal based at least in part on the series of samples of the at least one sensor signal, wherein: said ascertaining a residual portion further comprises ascertaining the residual portion of the at least one sensor signal based at least in part on the ascertained one or more principal components; and said determining at least one value associated with the residual portion further comprises estimating a characteristic of random noise expressed in a subspace associated with the residual portion of the at least one sensor signal, the characteristic comprising one or more values descriptive of how data are distributed with respect to an average of the data; and assessing a reliability of the at least one sensor signal to represent the blood glucose level of the patient based at least partly on the at least one metric.