Charlson Comorbidity scoring in pre-ICD10 codes

This page explains how the Charlson Comorbidity Index score is derived for data prior to Conversion from our old diagnosis schema to ICD10/CCI.

Short version

To get the Charlson comorbid points for a patient, use query pre_ICD10_Charlson_Score

Long version

Points are not included in the listings because the score depends on the combination of diagnoses. For example, if a patient has two diagnoses from the same Charlson component, they are only counted once. Also, if a patient has diagnoses from a lesser and more severe component of the same type (e.g. Diabetes without and with complications), only the higher one counts.

1. S_charlson_dxs table - the subset of S_AllDiagnoses table that would contribute to a Charlson score
2. query s_como - query to combine S_charlson_dxs table and S_AllDiagnoses table
3. query L_ICD10_Charlson_dxs - to list only those dxs from L_ICD10 table that contribute to the Charlson score
4. query L_ICD10_Charlson_component_points - to derive the max score per component
5. query L_ICD10_Charlson_score - to sum up the scores

This is then used by query Charlson_Score_pre_and_ICD10 to provide continuous Charlson Comorbidity Index scoring.