Page 80 - PhD GT

Recognition of the centrality of compulsive use as being the defining feature of dependence (American Psychiatric Association 1994) made possible the argument that dependence was a common phenomenon across different psychoactive substance use and indeed beyond. This in turn resulted in the development of scales that were able to measure the severity of dependence regardless of substance used and to make comparisons regarding severity between the different substances. One such attempt was the development of the Severity of Dependence Scale (Gossop et al. 1995). Derived from the Severity of Opiate Dependence Scale (Sutherland et al. 1986), the Severity of Dependence Scale, like the Leeds Dependence Questionnaire described below, was based upon the observation that people can demonstrate high levels of dependent behaviour (a strong desire to use in the face of harmful consequences and difficulty in refraining from use) even where a withdrawal syndrome is absent. Prolonged, regular and heavy use of some drugs (for example amphetamine) does not produce a withdrawal syndrome in the way that the use of opiates and alcohol reliably does. The authors of the Severity of Dependence Scale appear to stop short of examining the question of the nature of dependence directly, but refer to “the psychological components of dependence” as though the scale measured only some components of dependence; the authors of the SADQ made a similar claim to measuring only some of the components of dependence some twenty years earlier when they stated that subjective components of dependence were too difficult to measure (Stockwell et al. 1983). It is uncertain from these introductory remarks just what is the theoretical underpinning of the scale; what is the relationship between the physiological and the psychological components of dependence, if they are both part of the same phenomenon? If there are no physiological features based upon a withdrawal syndrome, is it the case that dependence cannot reach such degrees of severity as where there are? What are the implications, if this is not the case, of comparing severity of dependence across different types of substance use, or of poly substance use where some of the drugs used result in withdrawal syndromes and some do not?
The authors of the SDS state that the scale is “primarily a measure of compulsive use” which may not be all there is to dependence but is “a centrally important” component of it (Gossop et al. 1995 p. 612) and therefore the basis for selection of the scale items. They state that the psychological components with which the scale is concerned are “the individual’s feelings of impaired control over their own drug taking and with their preoccupation and anxieties about drug taking”. Specifically these are i) perceived impaired control over use ‘Did you think your use of (named drug) was out of control?’ ii) anxiety caused by the possible inability to use ‘Did the prospect of missing a fix (or dose) or not chasing make you anxious or worried?’ Items (iii) and (iv)
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