title: Differences in characteristics of pediatric patients undergoing computed tomography between hospitals and primary care settings: implications for assessing cancer follow-up studies.
abstract: BACKGROUND
  Recently published analyses showed that computed tomography (CT) scans in pediatric patients are associated with increased risk of radiation-related cancer. These analyses were based on data collected both from either hospitals and primary care services. Study objectives were to characterize cohorts of pediatric patients in Israel undergoing CT scans in primary care compared to hospitals settings. These cohorts will be further used for evaluating cancer risks.
  
  
  METHODS
  The present study was conducted in Schneider Children Medical Center in Israel (SCMCI), the largest tertiary pediatric hospital in the country. Data were collected directly from the listings of the pediatric radiology department for the period 1985-2005. Results were compared with previously published data on pediatric CT in the primary healthcare service performed between 1999 and 2003 in a large health organization, Maccabi Healthcare Services (MHS).
  
  
  RESULTS
  During the study observation periods, 38,351 and 22,223 examinations were documented in 13,726 and 18,075 pediatric patients in SCMCI and MHS, respectively. Compared to pediatric patients in the primary care, patients undergoing CT scans in the hospital were more likely to be younger, to have multiple CT scans, and to be scanned in the trunk. Also, cancer-related indications accounted for nearly 50 % of all CT scans conducted in the hospital compared to only 3 % in primary care settings.
  
  
  CONCLUSIONS
  The results indicate major differences in the characteristics of children and adolescents scanned in hospitals compared to primary care settings. Some of these characteristics may be associated with cancer risk later in life, and should be taken into account in cancer risk assessments.
authors.affiliation: Medical Division, Maccabi Healthcare Services, Tel Aviv, Israel ; Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD USA ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Chodick
authors.affiliation: Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Moran
authors.initials: M
authors.lastname: Levin
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD USA.
authors.forename: Ruth A
authors.initials: RA
authors.lastname: Kleinerman
authors.affiliation: Schneider Children's Medical Center in Israel, Petach-Tiqva, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Shwarz
authors.affiliation: Medical Division, Maccabi Healthcare Services, Tel Aviv, Israel ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Varda
authors.initials: V
authors.lastname: Shalev
authors.affiliation: Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel ; Schneider Children's Medical Center in Israel, Petach-Tiqva, Israel.
authors.forename: Shai
authors.initials: S
authors.lastname: Ashkenazi
authors.affiliation: Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel ; Schneider Children's Medical Center in Israel, Petach-Tiqva, Israel.
authors.forename: Gad
authors.initials: G
authors.lastname: Horev
keywords: Computed tomography; Hospitalization; Israel; Pediatrics