Table 2

Characteristics of the study population

CharacteristicCases*
N=60
References†
N=295
Sex, n (%)
 Male38 (63.3)190 (64.4)
 Female22 (36.7)105 (35.6)
Median age at index date‡ (IQI)11.3 (8.4–16.1)11.1 (7.7–15.7)
Age group at index date, n (%)
 Age <10 years21 (35.0)130 (44.1)
 Age ≥10 years39 (65.0)165 (55.9)
Treatment protocol, n (%)
 NOPHO ALL199224 (40.0)120 (40.7)
 NOPHO ALL200022 (36.7)105 (35.6)
 NOPHO ALL200814 (23.3)70 (23.7)
Cell line, n (%)
 B-precursor ALL55 (91.7)253 (85.8)
 T-ALL5 (8.3)42 (14.2)
Risk group, n (%)
 Non-high-risk46 (76.7)230 (78.0)
 High-risk14 (23.3)65 (22.0)
Median time from diagnosis to index date (years, IQI)3.8 (3.2–5.1)3.8 (3.2–5.1)
Type of event, n (%)
 Relapse49 (81.7)
 SMN11 (18.3)
  • *Cases, survivors of childhood ALL developing a relapse or an SMN as the first event.

  • †References, survivors of childhood ALL still in first remission matched on age, sex, treatment protocol and risk group.

  • ‡Index date, the date of event for cases and the corresponding date for references.

  • ALL, acute lymphoblastic leukaemia; IQI, interquartile interval; NOPHO, Nordic Society of Paediatric Haematology and Oncology; SMN, second malignant neoplasm.