Business Context
In a clinical trial analysis, researchers need to categorize patients into risk groups based on specific, medically-defined cut-off points for a 'biomarker_level'. These thresholds are absolute and must be applied precisely. The goal is to create four specific risk groups: 'Low', 'Medium', 'High', and 'Very High'.
About the Set : dataPreprocess
Data cleaning, imputation, and preprocessing.
Discover all actions of dataPreprocess Data Preparation
Creation of a large patient dataset with a continuous biomarker measurement.
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| 1 | DATA mycas.clinical_trial_data(copies=2); |
| 2 | call streaminit(789); |
| 3 | DO patient_id = 1 to 100000; |
| 4 | biomarker_level = rand('NORMAL', 20, 8); |
| 5 | IF biomarker_level < 0 THEN biomarker_level = 0; |
| 6 | OUTPUT; |
| 7 | END; |
| 8 | RUN; |
Étapes de réalisation
1
Apply user-defined binning using the 'CUTPTS' method with the specific clinical thresholds. Only copy the patient ID and the new binned variable to the output table for efficiency.
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| 1 | PROC CAS; |
| 2 | dataPreprocess.binning / |
| 3 | TABLE={name='clinical_trial_data'}, |
| 4 | inputs={{name='biomarker_level'}}, |
| 5 | method='CUTPTS', |
| 6 | cutPoints={15.0, 22.5, 30.0}, |
| 7 | copyVars={'patient_id'}, |
| 8 | outVarsNamePrefix='risk_group_', |
| 9 | casOut={name='patient_risk_groups', replace=true}; |
| 10 | RUN; |
| 11 | QUIT; |
2
Verify the binning results by checking the min and max biomarker levels within each generated risk group to ensure they align with the specified cut points.
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| 1 | PROC CAS; |
| 2 | SIMPLE.summary / |
| 3 | TABLE={name='patient_risk_groups', groupBy={'risk_group_biomarker_level'}}, |
| 4 | inputs={{name='biomarker_level'}}, |
| 5 | subSet={'MIN', 'MAX'}; |
| 6 | RUN; |
| 7 | QUIT; |
Expected Result
The action creates the 'patient_risk_groups' table. It contains 'patient_id' and a new column 'risk_group_biomarker_level'. The summary results will confirm that the data has been correctly partitioned: Bin 1 contains patients with biomarker_level <= 15.0; Bin 2 has levels > 15.0 and <= 22.5; Bin 3 has levels > 22.5 and <= 30.0; and Bin 4 has levels > 30.0.