A signal processing apparatus, comprising: an automatic analysis apparatus for analyzing a body fluid component of a specimen sample based on a detection signal from the specimen sample, the automatic analysis apparatus comprising a first A/D converter configured to sample the detection signal with a first sampling frequency and thus to acquire a first time-series signal with a first time resolution as the basis for analyzing the body fluid component of the specimen sample; and a second A/D converter configured to sample the detection signal with a second sampling frequency higher than the first sampling frequency and thus to acquire a second time-series signal with a second time resolution higher than the first time resolution; a data processing unit configured to process the second time-series signal; and a determination unit configured to determine a measurement abnormality of the automatic analysis apparatus; characterized in that the data processing unit is configured to smooth the second time-series signal in order to extract a peak position of the smoothed second time-series signal; and the determination unit is configured to extract a waveform shape feature amount associated with a peak position of the smoothed second time-series signal from the smoothed second time-series signal, to acquire a Mahalanobis distance between the extracted waveform shape feature amount and a reference data cluster of waveform shape feature amounts, and to determine the measurement abnormality of the automatic analysis apparatus based on the acquired Mahalanobis distance. an automatic analysis apparatus for analyzing a body fluid component of a specimen sample based on a detection signal from the specimen sample, the automatic analysis apparatus comprising a first A/D converter configured to sample the detection signal with a first sampling frequency and thus to acquire a first time-series signal with a first time resolution as the basis for analyzing the body fluid component of the specimen sample; and a second A/D converter configured to sample the detection signal with a second sampling frequency higher than the first sampling frequency and thus to acquire a second time-series signal with a second time resolution higher than the first time resolution; a first A/D converter configured to sample the detection signal with a first sampling frequency and thus to acquire a first time-series signal with a first time resolution as the basis for analyzing the body fluid component of the specimen sample; and a second A/D converter configured to sample the detection signal with a second sampling frequency higher than the first sampling frequency and thus to acquire a second time-series signal with a second time resolution higher than the first time resolution; a data processing unit configured to process the second time-series signal; and a determination unit configured to determine a measurement abnormality of the automatic analysis apparatus; characterized in that the data processing unit is configured to smooth the second time-series signal in order to extract a peak position of the smoothed second time-series signal; and the determination unit is configured to extract a waveform shape feature amount associated with a peak position of the smoothed second time-series signal from the smoothed second time-series signal, to acquire a Mahalanobis distance between the extracted waveform shape feature amount and a reference data cluster of waveform shape feature amounts, and to determine the measurement abnormality of the automatic analysis apparatus based on the acquired Mahalanobis distance. <EOS>