Data were analyzed using Chi-square and independent samples t-tests in SPSS 16 (SPSS Inc., Chicago, IL, USA) with P < 0.05 as significance level.



SPSS
Data were analyzed using Chi-square and independent samples t-tests in SPSS 16 (SPSS Inc., Chicago, IL, USA) with P < 0.05 as significance level.



SPSS Inc.
Data were analyzed using Chi-square and independent samples t-tests in SPSS 16 (SPSS Inc., Chicago, IL, USA) with P < 0.05 as significance level.



Chicago
Data were analyzed using Chi-square and independent samples t-tests in SPSS 16 (SPSS Inc., Chicago, IL, USA) with P < 0.05 as significance level.



IL
Data were analyzed using Chi-square and independent samples t-tests in SPSS 16 (SPSS Inc., Chicago, IL, USA) with P < 0.05 as significance level.



USA