Demographic data and clinical correlates.

*<p>Significant difference between controls and patients with schizophrenia (significant level at 0.05)Independent <i>t</i> test for continuous variables.</p><p>Pearson's chi-square (2-sided) test for categorical variables.</p><p>PPD: package per day.</p><p>d′: sensitivity index of undegraded CPT.</p><p>md′: sensitivity index of degraded CPT.</p

Demographic data between controls and patients with schizophrenia.

<p>SD: standard deviation; PPD: packs per day.</p>a<p>Independent <i>t</i> test for age, years of education and amount of smoking; Chi-square test for gender and smoker.</p>b<p><i>P</i>-values were 2-sided.</p

Correlation between MMN and neuropsychological tests.

<p>Pearson's partial correlation, controlling for age and affected status.</p

P50 parameters between the controls and patients with schizophrenia.

<p>SD: standard deviation.</p>a<p>The test statistics were obtained by independent <i>t</i> tests.</p>b<p><i>P</i>-values were 2-sided.</p

Grand average mismatch negativity waveforms.

<p>(<b>A</b>) Grand average mismatch negativity waveform at each electrode shown for schizophrenia patients (red line) and healthy subjects (blue line). The mismatch negativity waveform reversed in polarity at the mastoid electrodes. (<b>B</b>) Grand average MMN waveform at electrode Fz. (<b>C</b>) Grand average MMN waveform at electrode FCz.</p

Neuropsychological tests between controls and patients with schizophrenia.

<p>SD: standard deviation.</p>a<p>The test statistics were obtained by independent <i>t</i> tests.</p>b<p><i>P</i>-values were 2-sided.</p

Effects of age on mismatch negativity.

<p>Mean mismatch negativity amplitude (135–205 msec) at electrode Fz reduces with aging. The reduction rate were not significantly different between healthy control group (open circles and solid regression line) and schizophrenia group (crosses and dashed regression line).</p

Multivariable logistic regression model for schizophrenia.

<p>SE: standard error; CI: confidence interval.</p><p>Gating is defined as a dichotomous variable: P50 gating ratio greater than 0.4 or not.</p><p>Smoke is defined as a dichotomous variable: smoking or not.</p><p>^a Wald chi-square tests.</p><p>^b<i>P</i>-values were 2-sided.</p><p>Multivariable logistic regression model: n  = 160, percentage of concordant pairs  = 90.4%, percentage of discordant pairs  = 9.6%, c statistic  = 0.9043, Hosmer-Lemeshow Goodness-of-Fit test <i>p</i>  = .640>.05 (df  = 8).</p><p>The estimated probability of having schizophrenia (the predicted value, ) can be obtained by using the following formula:</p><p> where Gating equals 1 if P50 gating ratio >0.4, and 0 otherwise; Smoke equals 1 if smoking, and 0 otherwise.</p

Clinical symptom ratings in patients with schizophrenia by PANSS and dimension scores.

<p>Clinical symptom ratings in patients with schizophrenia by PANSS and dimension scores.</p

Current medication in Patients with Schizophrenia (<i>n</i> = 111).

<p>Current medication in Patients with Schizophrenia (<i>n</i> = 111).</p