Table 2

Selection of NHL cases and controls, selected cancers study, 1984–1988

Selection stepCasesControls
Lymphoma casesa/controlsb23542299
Interviewedc20731910
Pathology specimen obtained2004
Lymphoma diagnosis confirmedd1868
 Unclassifiable14
 Hodgkin’s disease confirmed343
 NHL confirmed1511
Excluded from analysise
 Acquired immunodeficiency syndrome2901
 Proxy interview2740
 Interview quality/interviewee cooperation suboptimal116113
 Major risk factor for AIDS4457
 Incomplete allergy history2753
Total study population9521691
  • a All cancer registry cases with initial diagnosis of NHL, Hodgkin’s disease, or “lymphoma not otherwise specified.”

  • b 91.4% (14,328/15,768) of households contacted by random-digit dialing provided eligibility information, 90.9% (4,381/4,822) with eligible men provided name and address, from which 2,299 men were randomly selected.

  • c 11.9% of cases and 16.9% of controls declined study participation, most often because of refusal to be interviewed.

  • d Confirmation of lymphoma diagnosis based on pathology specimen review by panel of pathologists with expertise in hematologic malignancies. Specimens considered inadequate for 129 of 136 unconfirmed cases.

  • e Total exclusions less than sum of individual exclusions because multiple exclusion categories apply.