SETIL: Italian multicentric epidemiological case–control study on risk factors for childhood leukaemia, non hodgkin lymphoma and neuroblastoma: study population and prevalence of risk factors in Italy

Table 4 SETIL study parental smoking status of controls classified according to child’s residence, and parental educational level

Paternal smoking is referred at child conception and maternal smoking during pregnancy.
Percentages are calculated by row, on subjects with available information.
^aNonsmoker category includes never smokers and fathers who quitted smoking at least the year before conception.
^bModerate smoker category includes fathers who quitted smoking in the year of the conception and smokers of 1–10 cigarettes per day in the period of the conception.
^cHeavy smoker category includes fathers that smoked 11 or more cigarettes per day in the period of the conception.
^dNonsmoker category includes never smokers and mothers who quitted smoking at least the year before the pregnancy.
^eModerate smoker category includes mothers who quitted smoking in the year of the pregnancy and women that smoked 1–100 packets of cigarettes during the pregnancy.
^fHeavy smoker category includes mothers that smoked 101 or more packets of cigarettes during the pregnancy.

ISSN: 1824-7288