Title | Establishment of an 11-year cohort of 8733 pediatric patients hospitalized at United States free-standing children's hospitals with de novo acute lymphoblastic leukemia from health care administrative data. |
Publication Type | Journal Article |
Year of Publication | 2014 |
Authors | Fisher BT, Harris T, Torp K, Seif AE, Shah A, Huang YS, L Bailey C, Kersun LS, Reilly AF, Rheingold SR, Walker D, Li Y, Aplenc R |
Journal | Med Care |
Volume | 52 |
Issue | 1 |
Pagination | e1-6 |
Date Published | 2014 Jan |
ISSN | 1537-1948 |
Keywords | Adolescent, Adult, Antineoplastic Agents, Child, Child, Preschool, Clinical Coding, Cohort Studies, Comparative Effectiveness Research, Female, Hospitalization, Hospitals, Pediatric, Humans, Infant, Male, Precursor Cell Lymphoblastic Leukemia-Lymphoma, United States, Young Adult |
Abstract | BACKGROUND: Acute lymphoblastic leukemia (ALL) accounts for almost one quarter of pediatric cancer in the United States. Despite cooperative group therapeutic trials, there remains a paucity of large cohort data on which to conduct epidemiology and comparative effectiveness research studies. RESEARCH DESIGN: We designed a 3-step process utilizing International Classification of Diseases-9 Clinical Modification (ICD-9) discharge diagnoses codes and chemotherapy exposure data contained in the Pediatric Health Information System administrative database to establish a cohort of children with de novo ALL. This process was validated by chart review at 1 of the pediatric centers. RESULTS: An ALL cohort of 8733 patients was identified with a sensitivity of 88% [95% confidence interval (CI), 83%-92%] and a positive predictive value of 93% (95% CI, 89%-96%). The 30-day all cause inpatient case fatality rate using this 3-step process was 0.80% (95% CI, 0.63%-1.01%), which was significantly different than the case fatality rate of 1.40% (95% CI, 1.23%-1.60%) when ICD-9 codes alone were used. CONCLUSIONS: This is the first report of assembly and validation of a cohort of de novo ALL patients from a database representative of free-standing children's hospitals across the United States. Our data demonstrate that the use of ICD-9 codes alone to establish cohorts will lead to substantial patient misclassification and result in biased outcome estimates. Systematic methods beyond the use of just ICD-9 codes must be used before analysis to establish accurate cohorts of patients with malignancy. A similar approach should be followed when establishing future cohorts from administrative data. |
DOI | 10.1097/MLR.0b013e31824deff9 |
Alternate Journal | Med Care |
PubMed ID | 22410405 |
PubMed Central ID | PMC3381055 |
Grant List | P30 CA016520 / CA / NCI NIH HHS / United States R01 CA133881 / CA / NCI NIH HHS / United States R01 CA133881-01 / CA / NCI NIH HHS / United States R01 CA133881-01A2 / CA / NCI NIH HHS / United States |