Evaluación de la competencia social.

2.5.1 The use of validated screening tools in clinical practice

The detection of AUDs is of great importance to healthcare professionals to ensure timely and appropriate treatment for patients (Cameron et al 2006). Accordingly, the use of appropriate screening instruments is crucial in order to identify, prevent and offer early treatment in clinical practice (Meneses-Gaya Crippa, Zuardi et al 2010, Pilling, Yesfu-Udechuku, Taylor et al 2011).

Asking patients to self-report on their drinking habits, usually leads to an estimate lower than the actual number of alcoholic drinks per day (O’Brien 2008). Further, the properties of screening tools have been shown to be superior to biomarkers such as gamma-glutamyl-transferase (GGT), mean corpuscular volume (MCV), aspartate transaminase (AST) and percent carbohydrate-deficient transferrins (%CDT) to detect patients with chronic heavy alcohol consumption in both primary care and trauma patients (Bernadt, Taylor, Mumford, et al 1982, Neumann, Gentilello, Neuner et al 2009).

This was exemplified by Neumann et al (2009), who undertook a prospective, single centre, observational cohort study in an emergency department in Germany between 2001 and 2003. The purpose of the study was to evaluate the diagnostic accuracy of the patient reported Alcohol Use Identification Test (AUDIT) as well as biomarkers for the detection of alcohol misuse (alcohol dependence or harmful use and/or at high risk) in injured patients and to determine if the combined use of the AUDIT and biomarkers was superior to the use of AUDIT alone. In Neumann's study, patients admitted to the emergency department were evaluated with the AUDIT (Appendix I) and blood sampled to determine %CDT, GGT and MCV. The final cohort consisted of 1233 patients (25% of patients approached, 787 males and 446 females). At a specificity >0.8, sensitivity for all biomarkers was <0.43, whereas sensitivity for the AUDIT was 0.76 (Area Under the Curve (AUC) 0.874, 95% Confidence Interval (CI): 0.842- 0.905) for males and 0.81 (AUC 0.889, 95% CI: 0.831-0.947) for females. Further, the addition of biomarkers added little information compared to the use of AUDIT in isolation. Despite the significance of this paper, one important study limitation should be noted. Patients with obvious intoxication were

excluded as the researchers could not gain fully informed consent. This may have influenced the performance of the AUDIT and biomarkers as an important group of patients were excluded.

The use of patient reported standard screening tools have also been shown to be more cost effective, with a lower cost per true positive for all consumption outcomes, rather than obtaining biomarkers (Coulton, Drummond, James et al 2006). Indeed, preventative cost efficiency studies related to alcohol screening and counselling have found that preventative services of this type were determined to have cost effectiveness ratios similar to what is observed in screening for colorectal cancer, hypertension and influenza (Burnham 2008).

Until the mid-1980’s, the four item ‘Cut-down, Annoyed, Guilty, Eye-Opener’ (CAGE) and the Michigan Alcohol Screening test (MAST) were the primary tools available for healthcare professionals in screening for alcohol use (Selzer 1971, Pokorny, Miller, Kaplan 1972, Mayfield, McLeod, Hall 1974). However, there are now many screening instruments available for the assessment of AUDs in health care practice (Kelly, Donovan, Chung et al 2009). Table 2.3 demonstrates the different screening tools available for AUDs in the clinical environment. Appendix I contains the contents of each of these screening tools. Furthermore, a full critique of these tools was published by our research group (McPeake, O'Neill, Kinsella 2013) (Appendix II).

2.5.2 Comparison of proxy and patient responses with alcohol screening tools

General concerns have been expressed about the reliability and validity of self- reports of alcohol intake (Donovan, Dunn, Rivara et al 2004). Despite substantial amounts of work demonstrating the reliability and validity of self-reporting tools such as the Fast Alcohol Screening Tool (FAST) and AUDIT, it has been proposed that further confirmatory information about the patient's drinking behaviours should be obtained whenever possible, as traditional models of alcoholism characterise denial as an important feature of the disorder (Donovan et al 2004). One way of obtaining further information regarding an individual’s drinking behaviours is to ask a next of kin (NOK) or a proxy for further information regarding the patients' drinking habits and behaviours. Such an approach has been utilised in a small number of seminal studies, where alongside the patient

completion of a validated tool such as CAGE or MAST, the patient proxy also completes the same questionnaire. Overall, these studies have found a high degree of consistency between patients' self-reports and those of their proxies (McCrady, Paolino, Longabaugh 1978, Leonard, Dunn, Jacob 1983, Chermack, Singer, Beresford 1998, Donovan et al 2004).

The use of proxy reporting does have its own potential problems and methodological issues, for example ensuring an appropriate proxy. Further, there appears to be no study which has analysed or validated these tools with either patients or patient proxies within the UK ICU environment.

Table 2.3: Alcohol screening tools in clinical practice (adapted from McPeake et al 2013)

Alcohol

Screening Tool

Acronym Details of tool Scoring Reliability measures Estimated time to complete Michigan Alcohol Screening Test (Selzer 1971,

MAST MAST has 25 questions

Items are scored either yes or no. In MAST a score of six or more indicates potential alcohol abuse.

In the B-MAST a score of more than 6 indicates ‘probable’ alcohol dependence. In SMAST a score of 4 or more indicates potential alcohol abuse. Reliability estimates centre around 0.8 from 62 studies (Shields, Howell, Potter et al 2007) MAST: 5 minutes Brief Michigan Alcohol Screening test (Pokorny et al 1972)

B-MAST B-MAST has 10 questions B-MAST: 3 minutes Short Michigan Alcohol Screening Test (Selzer, Vinokur, Van Rooijen 1975)

SMAST SMAST has 13 items SMAST: 3 minutes

Cut down, annoyed, Guilty, Eye Opener (Mayfield et al 1974, Ewing 1984)

CAGE Four item tool used to detect alcohol abuse and dependence

A point is scored for each positive

response. A score of 2 or more is considered the cut off for probable alcohol dependence. Test-retest reliability co efficient 0.80-0.95 (Dhalla and Kopec 2007) 30 seconds Alcohol Use Disorders Identification Test (Babor, de la Fuente, Saunders et al 1989) AUDIT 10 question survey. Can detect less severe forms of alcohol misuse

Individual answers are scored 0 to 4. Score range 0 to 40. A score of 8 or more (7 for women) indicates hazardous/ harmful alcohol consumption. A score of 14 or more in women and 15 or more in men is likely to indicate alcohol dependence. Median reliability co efficient of 0.83 in most recent review (Reinert and Allen 2007) 2 minutes Fast Alcohol Screening Tool (Hodgson, Alwyn, John et al 2002)

FAST Developed from the AUDIT tool. Based upon four AUDIT questions.

Consists of questions 3, 5, 8 and 10 of AUDIT. Question 3 has been modified. Score of 3-8: Hazardous drinking. Score of 9-16: Probable dependent drinking. Test-retest reliability of greater than 0.8 20-30 seconds

2.6 The Intensive Care Unit (ICU)