Displayed Output

The FREQ Procedure

Displayed Output

PROC FREQ displays one-way frequency tables for all one-way table requests in the TABLES statements, unless you specify the NOPRINT option in the PROC statement or the NOPRINT option in the TABLES statement. For a one-way table showing the frequency distribution of a single variable, PROC FREQ displays the following information:

the name of the variable and its values
Frequency counts, giving the number of observations that have each value
specified Test Frequency counts, if you specify the CHISQ and TESTF= options to request a chi-square goodness-of-fit test for specified frequencies
Percent, giving the percentage of the total number of observations with that value. (The NOPERCENT option suppresses this information.)
specified Test Percents, if you specify the CHISQ and TESTP= options to request a chi-square goodness-of-fit test for specified percents. (The NOPERCENT option suppresses this information.)
Cumulative Frequency counts, giving the sum of the frequency counts of that value and all other values listed above it in the table. The last cumulative frequency is the total number of nonmissing observations. (The NOCUM option suppresses this information.)
Cumulative Percent values, giving the percentage of the total number of observations with that value and all others previously listed in the table. (The NOCUM or the NOPERCENT option suppresses this information.)
Frequency Missing, or the number of observations with missing values

For one-way tables, two statistical options are available in the TABLES statement. The CHISQ option provides a chi-square goodness-of-fit test, and the BINOMIAL option provides binomial proportion statistics. PROC FREQ displays the following information, unless you specify the NOPRINT option in the PROC statement:

If you specify the CHISQ option for a one-way table, PROC FREQ provides a chi-square goodness-of-fit test, displaying the Chi-Square statistic, the degrees of freedom (DF), and the probability value (Pr > ChiSq). If you specify the CHISQ option in the EXACT statement, PROC FREQ also displays the exact probability value for this test.
If you specify the BINOMIAL option for a one-way table, PROC FREQ displays the estimate of the binomial Proportion, which is the proportion of observations in the first class listed in the one-way table. PROC FREQ also displays the asymptotic standard error (ASE) and the asymptotic and exact confidence limits for this estimate. For the binomial proportion test, PROC FREQ displays the asymptotic standard error under the null hypothesis (ASE Under H0), the standardized test statistic (Z), and the one-sided and two-sided probability values. If you specify the BINOMIAL option in the EXACT statement, PROC FREQ also displays the exact one-sided and two-sided probability values for this test.

PROC FREQ displays all multiway table requests in the TABLES statements, unless you specify the NOPRINT option in the PROC statement or the NOPRINT option in the TABLES statement. PROC FREQ displays multiway tables either as crosstabulation tables (the default) or as lists (when you specify the LIST option).

For two-way to multiway crosstabulation tables, the values of the last variable in the table request form the table columns. The values of the next-to-last variable form the rows. Each level (or combination of levels) of the other variables form one stratum. PROC FREQ produces a separate two-way crosstabulation table for each stratum. Each cell of a crosstabulation table may contain the following information:

Frequency, giving the number of observations that have the indicated values of the two variables. (The NOFREQ option suppresses this information.)
the Expected cell frequency under the hypothesis of independence, if you specify the EXPECTED option
the Deviation of the cell frequency from the expected value, if you specify the DEVIATION option
Cell Chi-Square, which is the cell's contribution to the total chi-square statistic, if you specify the CELLCHI2 option
Tot Pct, or the cell's percentage of the total frequency, for n-way tables when n>2, if you specify the TOTPCT option
Percent, the cell's percentage of the total frequency. (The NOPERCENT option suppresses this information.)
Row Pct, or the row percentage, the cell's percentage of the total frequency count for that cell's row. (The NOROW option suppresses this information.)
Col Pct, or column percentage, the cell's percentage of the total frequency count for that cell's column. (The NOCOL option suppresses this information.)
Cumulative Col%, or cumulative column percent, if you specify the CUMCOL option
Frequency Missing, or the number of observations with missing values

If you specify the LIST option in the TABLES statement, PROC FREQ displays multiway tables in a list format rather than as crosstabulation tables. PROC FREQ ignores the LIST option when you also request statistical options. For a multiway table in list format, PROC FREQ displays the following information:

the variable names and values
Frequency counts, giving the number of observations with the indicated combination of variable values
Percent, the cell's percentage of the total number of observations. (The NOPERCENT option suppresses this information.)
Cumulative Frequency counts, giving the sum of the frequency counts of that cell and all other cells listed above it in the table. The last cumulative frequency is the total number of nonmissing observations. (The NOCUM option suppresses this information.)
Cumulative Percent values, giving the percentage of the total number of observations for that cell and all others previously listed in the table. (The NOCUM or the NOPERCENT option suppresses this information.)
Frequency Missing, or the number of observations with missing values

PROC FREQ computes statistical tests and measures for crosstabulation tables, depending on which statements and options you specify. You can suppress the display of all these results by specifying the NOPRINT option in the PROC statement. With any of the following information, PROC FREQ also displays the Sample Size and the Frequency Missing.

If you specify the SCOROUT option, PROC FREQ displays the Row Scores and Column Scores that it uses for statistical computations. The Row Scores table displays the row variable values and the Score corresponding to each value. The Column Scores table displays the column variable values and the corresponding Scores. PROC FREQ also identifies the score type used to compute the row and column scores. You can specify the score type with the SCORES= option in the TABLES statement.
If you specify the CHISQ option, PROC FREQ displays the following statistics for each two-way table: Pearson Chi-Square, Likelihood-Ratio Chi-Square, Continuity-Adjusted Chi-Square, Mantel-Haenszel Chi-Square, Fisher's Exact Test (for 2 ×2 tables), the Phi Coefficient, the Contingency Coefficient, and Cramer's V. For each test statistic, PROC FREQ also displays the degrees of freedom (DF) and the probability value (Prob). If you specify the PCHI option, the LRCHI option, or the MHCHI option in the EXACT statement, PROC FREQ also displays the exact probability value for the Pearson Chi-Square, the Likelihood-Ratio Chi-Square, or the Mantel-Haenszel Chi-Square, respectively. If you specify the CHISQ option in the EXACT statement, PROC FREQ displays exact probability values for all three of these chi-square tests.
If you specify the FISHER option in the TABLES statement (or, equivalently, the FISHER option in the EXACT statement), PROC FREQ displays the probability value for Fisher's exact test for tables larger than 2 ×2. In addition, PROC FREQ displays the CHISQ output listed earlier, even if you do not also specify the CHISQ option.
If you specify the MEASURES option, PROC FREQ displays the following statistics and their asymptotic standard errors (ASE) for each two-way table: Gamma, Kendall's Tau-b, Stuart's Tau-c, Somers' D(C|R), Somers' D(R|C), Pearson Correlation, Spearman Correlation, Lambda Asymmetric (C|R), Lambda Asymmetric (R|C), Lambda Symmetric, Uncertainty Coefficient (C|R), Uncertainty Coefficient (R|C), and Uncertainty Coefficient Symmetric. If you specify the CL option, PROC FREQ also displays confidence limits for these measures.
If you specify the PLCORR option, PROC FREQ displays the tetrachoric correlation for 2 ×2 tables or the polychoric correlation for larger tables. In addition, PROC FREQ displays the MEASURES output listed earlier, even if you do not also specify the MEASURES option.
If you specify the option GAMMA, KENTB, STUTC, SMDCR, SMDRC, PCORR, or SCORR in the TEST statement, PROC FREQ displays asymptotic tests for Gamma, Kendall's Tau-b, Stuart's Tau-c, Somers' D(C|R), Somers' D(R|C), the Pearson Correlation, or the Spearman Correlation, respectively. If you specify the MEASURES option in the TEST statement, PROC FREQ displays all these asymptotic tests. The test output includes the statistic, its asymptotic standard error (ASE), Confidence Limits, the ASE under the null hypothesis H0, the standardized test statistic (Z), and the one-sided and two-sided probability values.
If you specify the PCORR or SCORR option in the EXACT statement, PROC FREQ displays asymptotic and exact tests for the Pearson Correlation or the Spearman Correlation, respectively. The test output includes the correlation, its asymptotic standard error (ASE), Confidence Limits, the ASE under the null hypothesis H0, the standardized test statistic (Z), and the asymptotic and exact one-sided and two-sided probability values.
If you specify the RISKDIFF option for 2 ×2 tables, PROC FREQ displays the Column 1 and Column 2 Risk Estimates. For each column, PROC FREQ displays Row 1 Risk, Row 2 Risk, Total Risk, and Risk Difference, together with their asymptotic standard errors (ASE), Asymptotic Confidence Limits, and Exact Confidence Limits. Exact confidence limits are not available for the risk difference.
If you specify the MEASURES option or the RELRISK option for 2 ×2 tables, PROC FREQ displays Estimates of the Relative Risk for Case-Control and Cohort studies, together with their Confidence Limits. These measures are also known as the Odds Ratio and the Column 1 and 2 Relative Risks. If you specify the OR option in the EXACT statement, PROC FREQ also displays Exact Confidence Limits for the Odds Ratio.
If you specify the TREND option, PROC FREQ displays the Cochran-Armitage Trend Test for tables that are 2 ×C or R ×2. For this test, PROC FREQ gives the Statistic (Z) and the one-sided and two-sided probability values. If you specify the TREND option in the EXACT statement, PROC FREQ also displays the exact one-sided and two-sided probability values for this test.
If you specify the JT option, PROC FREQ displays the Jonckheere-Terpstra Test, showing the Statistic (JT), the standardized test statistic (Z), and the one-sided and two-sided probability values. If you specify the JT option in the EXACT statement, PROC FREQ also displays the exact one-sided and two-sided probability values for this test.
If you specify the AGREE option and the PRINTKWT option, PROC FREQ displays the Kappa Coefficient Weights for square tables greater than 2 ×2.
If you specify the AGREE option, for two-way tables PROC FREQ displays McNemar's Test and the Simple Kappa Coefficient for 2 ×2 tables. For square tables larger than 2 ×2, PROC FREQ displays Bowker's Test of Symmetry, the Simple Kappa Coefficient, and the Weighted Kappa Coefficient. For McNemar's Test and Bowker's Test of Symmetry, PROC FREQ displays the Statistic (S), the degrees of freedom (DF), and the probability value (Pr > S). If you specify the MCNEM option in the EXACT statement, PROC FREQ also displays the exact probability value for McNemar's test. For the simple and weighted kappa coefficients, PROC FREQ displays the kappa values, asymptotic standard errors (ASE), and Confidence Limits.
If you specify the KAPPA or WTKAP option in the TEST statement, PROC FREQ displays asymptotic tests for the simple kappa coefficient or the weighted kappa coefficient, respectively. If you specify the AGREE option in the TEST statement, PROC FREQ displays both these asymptotic tests. The test output includes the kappa coefficient, its asymptotic standard error (ASE), Confidence Limits, the ASE under the null hypothesis H0, the standardized test statistic (Z), and the one-sided and two-sided probability values.
If you specify the KAPPA or WTKAP option in the EXACT statement, PROC FREQ displays asymptotic an d exact tests for the simple kappa coefficient or the weighted kappa coefficient, respectively. The test output includes the kappa coefficient, its asymptotic standard error (ASE), Confidence Limits, the ASE under the null hypothesis H0, the standardized test statistic (Z), and the asymptotic and exact one-sided and two-sided probability values.
If you specify the AGREE option, for multiple strata PROC FREQ displays Overall Simple and Weighted Kappa Coefficients, with their asymptotic standard errors (ASE) and Confidence Limits. PROC FREQ also displays Tests for Equal Kappa Coefficients, giving the Chi-Squares, degrees of freedom (DF), and probability values (Pr > ChiSq) for the Simple Kappa and Weighted Kappa. For multiple strata of 2 ×2 tables, PROC FREQ displays Cochran's Q, giving the Statistic (Q), the degrees of freedom (DF), and the probability value (Pr > Q).
If you specify the CMH option, PROC FREQ displays Cochran-Mantel-Haenszel Statistics for the following three alternative hypotheses: Nonzero Correlation, Row Mean Scores Differ (ANOVA Statistic), and General Association. For each of these statistics, PROC FREQ gives the degrees of freedom (DF) and the probability value (Prob). For 2 ×2 tables, PROC FREQ also displays Estimates of the Common Relative Risk for Case-Control and Cohort studies, together with their confidence limits. These include both Mantel-Haenszel and Logit stratum-adjusted estimates of the common Odds Ratio, Column 1 Relative Risk, and Column 2 Relative Risk. Also for 2 ×2 tables, PROC FREQ displays the Breslow-Day Test for Homogeneity of the Odds Ratios. For this test, PROC FREQ gives the Chi-Square, the degrees of freedom (DF), and the probability value (Pr > ChiSq).

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