Derived Variables Clause Samples

Derived Variables. An estimate of disease severity was determined by the number of ACR criteria met at baseline. The higher the number, the worse the severity of the disease. Length of stay was created using the admission and discharge date to count the number of days each patient was hospitalized at their first hospital admission. Total number of hospitalizations summed the number of times a patient was hospitalized within the surveillance period. The insurance status was created using the insurance billed at the time of first hospital admission. Patients insured by Blue Cross/Blue Shield, commercial insurance, HMO/managed care, POS or PPO were considered insured. Patients covered by Georgia Better Health, Medicaid, Medicaid applicants or Medicaid managed care were considered insured by Medicaid. Patients covered by Medicare or Medicare managed care were considered insured by Medicare. Patients covered by Tricare or other providers were excluded from the variable insurance grouped, as it was too few patients to create its own category. Age was calculated at the date of diagnosis and at the time of first hospital admission.