Independence day? A team of the University of Geneva develops a new test to assess dependence on cigarettes
Tobacco smoking is the first avoidable cause of diseases and death in Switzerland. More than 30% of the Swiss population smokes, even though smoking causes 8500 deaths per annum in our country, generating a social cost evaluated between 5 and 10 billion Swiss francs (= 3.3-6.6 billion US$, or 3.4-6.8 billion euros). In addition, the proportion of young smokers strongly increased in recent years in Switzerland, particularly among girls. In this alarming context, the research group led by Jean-François Etter of the Institute of social and preventive medicine of the University of Geneva (Switzerland) developed a new test to evaluate the degree of dependence on cigarettes: the CDS (Cigarette Dependence Scale). Result of several surveys carried out during two years according to very strict criteria, this new instrument intends to provide a precise diagnosis and to become a reference in the assessment of tobacco dependence.
"Smoking seriously damages your health". Even though this warning is printed on all cigarette packages sold in Switzerland, tobacco smoking still causes one in seven deaths in our country. Dependence on tobacco- which is defined as the compulsive use of a substance in spite of its negative effects - is among the main factors responsible for this situation. This led the research group conducted by Jean-François Etter of the Institute of social and preventive medicine of the University of Geneva (Switzerland) to develop a new test to assess dependence on cigarettes. Its objective is to provide smokers, researchers and health care professionals with a new, precise instrument to evaluate the degree of dependence quantitatively.
Currently, two methods are used to assess tobacco dependence. First, the Fagerström test for nicotine dependence - developed 25 years ago by Swedish professor Karl Olov Fagerström - is a questionnaire that is still today the most frequently used measurement instrument. The second approach consists of standardized clinical interviews, which lead to a diagnosis of whether or not a person is dependent on tobacco, but do not provide a quantitative assessment of dependence.
Considering these tools somewhat unsatisfactory, the team of J.-F. Etter undertook to develop a new questionnaire to quantify precisely the degree of dependence on cigarettes. They proceeded as follows.
They started by investigating the symptoms of dependence on cigarettes. The researchers asked more than 500 French-speaking smokers to answer open-ended questions about cigarette dependence (384 in a mailed survey and 145 on the internet). The team received more than 800 short assertions concerning smoking and dependence. Then, they proceeded to a synthesis of answers to these preliminary surveys, based on current theories on dependence. In the next step, they prepared a new survey of 114 questions, in which 3000 people took part on the internet. The scientists used several tests to assess the validity of these 114 questions, and they chose the questions that had the best statistical properties. By collecting samples of saliva in some participants, they could observe an objective correlation between the quantity of cotinine (a breakdown product of nicotine) contained in the saliva and the level of dependence on cigarettes. Some participants answered the questionnaire twice, which enabled the researchers to assess whether the test was sensitive enough to detect change over time in the level of dependence.
Eliminating the less valid questions, the team finally retained 12 questions which have excellent statistical properties and constitute today the final version of the CDS (Cigarette Dependence Scale). This instrument makes it possible for clinicians to obtain a precise diagnosis, in order to prescribe an adequate treatment of dependence to smokers. But the CDS is also intended for researchers, for whom a precise evaluation of dependence is essential, for example during the development of new drugs to treat tobacco dependence.
An article on the CDS was published by Jean-François Etter, Jacques Le Houezec and Thomas Perneger in the scientific journal Neuropsychopharmacology. It is available on the internet at the address: www.acnp.org/citations/Npp071502348/ (Table 5).