charlson_list           List of Charlson comorbidities
charlson_weights        Map of Charlson comorbidity categories to
                        revised weights
charlson_weights_orig   Map of Charlson comorbidity categories to
                        weights
elixhauser_list         List of Elixhauser comorbidities
generate_charlson_index_df
                        Calculate the Charlson Comorbidity Index
generate_comorbidity_df
                        Generate a comorbidity dataframe
icd9cm_charlson_deyo    Create Deyo map of ICD-9-CM to Charlson
                        comorbidities
icd9cm_charlson_quan    Create Quan map of ICD-9-CM to Charlson
                        comorbidities
icd9cm_charlson_romano
                        Create Romano map of ICD-9-CM to Charlson
                        comorbidities
icd9cm_elixhauser_ahrq37
                        Create AHRQ v3.7 map of ICD-9-CM to Elixhauser
                        comorbidities
icd9cm_elixhauser_quan
                        Create Quan map of ICD-9-CM to Elixhauser
                        comorbidities
icd9cm_list             List of ICD-9-CM diagnostic and procedural
                        codes
icd9cm_rcri             Create Map of ICD-9-CM to Revised Cardiac Risk
                        Index classes
icd9cm_sessler_rsi      Returns composite Sessler risk stratification
                        index, given a list of ICD-9-CM codes.
melt_icd9list           Convert ICD-9-CM code list to dataframe
merge_icd9_dx_and_procs
                        Merge ICD-9-CM diagnostic and procedure codes
rsi_beta_1yrpod         Values for calculating RSI for 1 year mortality
rsi_beta_30dlos         Values for calculating RSI for 30-day length of
                        stay
rsi_beta_30dpod         Values for calculating RSI for 30-day mortality
rsi_beta_inhosp         Values for calculating RSI for in-hospital
                        mortality.
rsi_sample_data         Sample data for validating RSI
rsi_sample_results      Sample results for validating RSI
sessler_get_single_beta
                        Returns the covariate coefficient for a
                        particular diagnosis or procedure code, along
                        with the actual code that was found in the
                        internal database of coefficients. If a child
                        code is supplied but its parent is in the
                        database, the coefficient for the parent will
                        be returned, along with that parent code. For
                        example, if D1231 is supplied but only D123 is
                        available, D123 will be used. This is
                        apparently how the SPSS sample code works.
verify_sessler_rsi      Validates this Sessler RSI implementation
                        against reference data
vt_inp_sample           First 100 patients and their ICD-9-CM codes
                        from the Vermont Uniform Hospital Discharge
                        Data Set for 2011, Inpatient.
