Methods of Assessing Alcohol Craving

by National Institute of Health

(Page 3 of 5)

Assessment tools for craving generally fall into two broad categories: selfreport instruments and behavioral and psychophysiological measures. Selfreport instruments typically are questionnaires that can be either filled out by the patients themselves or administered by clinicians. These instruments are frequently used in both research and clinical settings. Behavioral and psychophysiological measures are primarily used in experimental settings.

Self-Report Instruments

Self-report is the most frequently used method to obtain information about craving. In everyday clinical practice, therapists usually administer singleitem instruments on which the patient reports his or her level of subjective craving. These instruments include questions such as "How strong is your craving for alcohol?" or "How strong is your urge to drink?" The therapist also provides anchor statements, such as "not at all" and "the most I've ever felt." The patient then rates his or her craving either by selecting the most appropriate choice on a 7- or 10-point scale or by indicating a vertical mark along a line that connects the two anchor statements. With VAS scales, the distance between the "no-craving" end of the line and the patient's mark serves as the index of craving. For both types of assessment, the patient may be asked to rate his or her current level of craving or average level of craving over a longer time period.

Brief Likert-type and VAS scales provide a straightforward and timeeffective approach to assessing a patient's level of subjective craving. However, as noted earlier, these assessments are limited in their ability to provide information about the multiple elements that can define the craving experience. Furthermore, researchers cannot determine the internal consistency of the instrument used. Because of these limitations, brief Likert-type or VAS ratings should be supplanted with multi-item instruments with desirable psychometric properties whenever possible. Several such instruments are described in the following paragraphs.

The Yale-Brown Obsessive Compulsive Scale for Heavy Drinking (Y-BOCS- hd). This scale, which was adapted from the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), was the first multi-item instrument developed and validated for the specific purpose of measuring craving for alcohol. The Y-BOCS-hd conceptualizes alcohol craving as obsessions and compulsions relating to alcohol consumption. The term "obsession" refers here to the frequency and intrusive nature of thoughts about drinking, especially after 1 or 2 days of abstinence, whereas the term "compulsion" refers to the loss of control over drinking.

The Y-BOCS-hd consists of 10 questions, of which 5 comprise an obsessionality subscale and the remaining 5 comprise a compulsivity subscale. The instrument is administered in a structured clinical interview lasting approximately 15 to 30 minutes.

In a study assessing the validity and reliability of the Y-BOCS-hd, Modell and colleagues administered the questionnaire to 62 alcoholics. The results were then compared with ratings from a single-item subjective craving measure. The study found that for both the total score and the two subscale scores, a statistically significant, albeit moderate, correlation existed between the ratings obtained with the two instruments.

The Obsessive Compulsive Drinking Scale (OCDS). Anton and colleagues modified the Y-BOCS-hd to derive the Obsessive Compulsive Drinking Scale, a 14-item questionnaire that the patient can selfadminister and complete in about 5 minutes. Because the instrument is selfadministered, each respondent is likely to interpret the questions similarly each time that he or she completes the questionnaire, thereby improving test-retest reliability and eliminating or reducing interviewer bias and differences in interpretation between interviewer and respondent. The OCDS is a global measure in which patients are asked to rate their craving over a period of 1 or 2 weeks (but no less than 1 day).

Like the Y-BOCS-hd, the OCDS contains an obsessive subscale, which consists of eight items, and a compulsive subscale, which consists of six items. However, the questions in the obsessive subscale on the OCDS relate to the occurrence of intrusive thoughts about alcohol at any time when the respondent is not drinking and thus encompass a more general timeframe than that specified in the Y-BOCS-hd. Patients respond to each item by selecting one of five statements that range from minimal to maximum endorsement of the item. The OCDS has demonstrated good test-retest reliability and high internal consistency; furthermore, its scores are strongly and significantly correlated with ratings obtained with the Y-BOCS-hd. The OCDS also has been shown to be a valuable tool for outcome assessment and for monitoring a patient's progress during treatment.

The Alcohol Craving Questionnaire (ACQ). The self-administered ACQ contains 47 items, each of which is scored on a 7-point Likert-type scale ranging from "strongly disagree" to "strongly agree." Each item is related to one of five domains that are considered relevant to alcohol craving: desire to drink alcohol, intention to drink alcohol, lack of control over the use of alcohol, anticipation of positive effects from drinking (positive outcome expectancy), and expectancy of relief from withdrawal or alcohol's negative effects. The ACQ is a state measure providing an index of acute craving, because the questions relate to the degree to which the respondent is currently experiencing these urges. Initial validation work with the ACQ revealed four dimensions with moderate to high internal consistency. These factors were labeled emotionality, purposefulness, compulsivity, and expectancy. The ACQ also has been modified into a short form, the ACQ-SF, that contains the 12 items most strongly correlated with the total ACQ score.

The Alcohol Urge Questionnaire (AUQ). The AUQ is an eight-item, self-administered state measure that assesses the patient's urge for an alcoholic drink at the time the questionnaire is completed, thereby providing an index of acute craving. As with the ACQ, the items are scored along a seven-point Likert-type scale. The AUQ contains four items pertaining to the desire for a drink, two items regarding expectations of positive effects from drinking and two items relating to the inability to avoid drinking if alcohol were present. The AUQ has demonstrated good test-retest reliability, both after a 1-day and 1-week interval. Furthermore, the instrument has shown significant (but moderate) positive correlations with the patient's alcoholdependence severity and with scores on the OCDS, as well as a negative correlation with the length of time the patient has been abstinent.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.