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drinking repertoire is said to be one, and then to use this as a criterion measure against which to validate the scale.
Nevertheless, the SADQ is a widely used scale. Criticisms of the SADQ, some of which are summarised by Davidson (1987), are that it does not measure all elements of the dependence syndrome and in fact only covers physical withdrawal and relief drinking, that it fails to measure the element described as “a leading symptom”, namely “impaired control over intake of the drug ethyl alcohol” (Edwards et al. 1977a p. 17), and that it has been validated in specialist clinical samples and not in the general population when claims for it are that it measures a phenomenon which is continuous and must therefore be detectable in the general population. Responding to these criticisms, Stockwell et al. (1994) adapted the SADQ for use in a community sample. They made a number of changes to the instructions and response choices and, without changing the item wording at all, administered the original and the adapted questionnaires to a general population sample and attenders at a controlled drinking clinic. Scores for the adapted scale, the SADQ-C correlated very highly with scores for the SADQ in the clinic sample. Correlations for the sections of the SADQ-C and the five item Impaired Control Questionnaire (ICQ) (discussed below in Chapter 5) were also high and Principal Components Analysis revealed a single factor accounting for 71.7% of the variance.
In the community sample, both SADQ-C items and ICQ were frequently positively endorsed. However, in Principal Components Analysis and correlational analyses, the reinstatement section items loaded on a different factor to the main factor on which all other SADQ-C scores loaded and which accounted for 50.8% of the variance. In the previous discussion, the inclusion of reinstatement as one of the elements of dependence was questioned.
In summary the authors conclude that, again, alcohol dependence has been shown to be a uni-dimensional construct whether applied to problem drinkers or to all people who drink regularly. Furthermore, they assert that:
“the failure of the ‘Reinstatement’ of dependence items in the SADQ-C for the community sample should not be interpreted as indicating a lack of coherence of the Alcohol Dependence Syndrome concept. The high frequency of positive responses to these items in the absence of positive responses to other dependence items indicates that they only measure beliefs about
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