We see relatively high cessation rates for those with neoplasms (18 %), and diseases of the genitourinary system (13%%), and low cessation rates in the congenital anomalies and endocrine, nutritional, and metabolic systems diseases categories (less than 4%%).
Higher socioeconomic status as measured by education, occupation and income, was associated with a higher cessation rate (p<0.001 for all three indicators of socioeconomic status).
Our findings are consistent with the results of a study of a hospital-based cessation programme where participants who used NRT for 5 weeks or longer were found to have a higher cessation rate at 6 month follow-up.
Injecting drug users who do not enter opiate substitution treatment might have different characteristics (for example, be less chaotic or dependent) that explain their higher cessation rate and confound the relation between long term cessation and opiate substitution treatment.
The only study to include a pregnant smoker comparison group was a very small (n = 44) matched controlled study which found a significantly higher cessation rate among women taking bupropion (45% vs 14%, p = 0.047).
As regards primary analysis 1, conservatively assuming a 5-year cessation rate of 20% in the TC group, and 30% in the Mixed group (EC group most probably having a higher cessation rate), we would need 313 subjects per group to achieve a power of 80%.
The highest cessation rate was among those who used prescription medication and behavioural counselling (20.4%) followed by those who used NRT and behavioural counselling (17.4%), attempted to quit unassisted (16.4%), used behavioural counselling only (16.1%) and those who used prescription medication only (15.3%).
We find notably higher cessation rates among younger beneficiaries in our population.
Some of these studies have reported that higher education levels are associated with higher cessation rates.
Albertsen et al. [ 29] found a U-shaped curve with highest cessation rates in the lowest and highest age groups.
