PEPI Version 4.0
----------------
The main changes since Version 3.0 are:

WHATIS (a PEPI-for-Windows program) has been added.

Additions and changes have been made to the following programs:

- CASECONT 

     Added features: DerSimonian-Laird procedure for computing an 
     overall odds ratio for a set of studies or strata (random-effects 
     model); exact power of Fisher and mid-P exact binomial tests; 
     faster computation of exact probabilities and confidence 
     intervals.  
     
- COMBINE

     Added features: DerSimonian-Laird procedure for computing an
     overall measure of association for a set of studies or strata
     (random-effects model); computation and combination of effect
     sizes (standardized differences between means); can accept
     confidence intervals (instead of standard errors) for the
     measures to be combined.
     
- CONFINT  

     Added features: New confidence intervals for differences between
     independent proportions and proportions based on paired data;
     faster computation; accuracy enhanced by use of improved function
     for estimating F from a P value.
     
- DIFFER 

     Added feature: estimation of effect of regression to the mean.
     
- EXACT2XK

     Faster computation.

- KAPPA    

     Added features: measure of distinguishability of categories;    
     percentage agreement in stratified data; confidence intervals for
     size=of=sample weighted values; kappa values that compensate for
     the effects of bias and unequal prevalences of categories; kappa
     for stratified data, appropriate for small samples.

- MANNWHIT                                                           

     Added features: Kolmogorov-Smirnov two-sample test;  Cramer-von
     Mises test for tabular data; confidence intervals for the odds
     estimate; correction for ties is calculation of Kendall
     coefficient.
     
- MANTELX

     Added features: heterogeneity test and cumulative odds ratio
     added to the extended Mantel-Haenszel procedure.

- MATCHED

     Added features: estimates conditional power of Walter's test for
     binary data (comparing cases with multiple matched controls);
     faster computation of exact probabilities and confidence
     intervals.


- MISCLASS
     Added feature: confidence intervals for modified odds and risk
     ratios.
              
                                                                     
- PAIRS  

     Added features: correlation and regression coefficients for 
     relationship between difference and mean of log-transformed
     values; faster computation of exact probabilities and confidence
     intervals; accuracy enhanced by use of improved function for
     estimating F from a P value.
     
- PVALUE   

     Added feature: Accuracy enhanced by use of improved function for
     estimating F from a P value.

- RATES1                           

     Added feature: DerSimonian-Laird procedure for computing an
     overall rate ratio and rate difference for a set of studies or
     strata (random-effects model).
    
- RATES2
     
     Added features: Heterogeneity tests based on Mantel-Haenzel
     estimator of common rate ratio and rate difference; "sparse-data"
     method for Mantel-Haenszel rate difference; improved confidence
     intervals for attributable and prevented fractions in the
     population; DerSimonian-Laird procedure for computing an overall
     rate ratio and rate difference; faster computation of exact
     probabilities and confidence intervals.

- SCRN

     Added features: Kullback-Leibler distances; comparison of two
     tests when a "gold standard" test is performed only on subjects
     with positive results; measures of relative accuracy; ROC curve
     showing the association between sensitivity and the false
     positive rate; area under the ROC curve; optimal cut-points under
     different conditions; improved estimation of confidence interval
     for disease prevalence.

- SEASONAL 

     Added feature: Hewitt's rank-sum test for seasonality.

- WHATS 
                                                    
     Added features: permutations and combinations; extended factorial
     function.


