title: Development and validation of a risk model for prediction of hazardous alcohol consumption in general practice attendees: the predictAL study.
abstract: BACKGROUND
  Little is known about the risk of progression to hazardous alcohol use in people currently drinking at safe limits. We aimed to develop a prediction model (predictAL) for the development of hazardous drinking in safe drinkers.
  
  
  METHODS
  A prospective cohort study of adult general practice attendees in six European countries and Chile followed up over 6 months. We recruited 10,045 attendees between April 2003 to February 2005. 6193 European and 2462 Chilean attendees recorded AUDIT scores below 8 in men and 5 in women at recruitment and were used in modelling risk. 38 risk factors were measured to construct a risk model for the development of hazardous drinking using stepwise logistic regression. The model was corrected for over fitting and tested in an external population. The main outcome was hazardous drinking defined by an AUDIT score ≥8 in men and ≥5 in women.
  
  
  RESULTS
  69.0% of attendees were recruited, of whom 89.5% participated again after six months. The risk factors in the final predictAL model were sex, age, country, baseline AUDIT score, panic syndrome and lifetime alcohol problem. The predictAL model's average c-index across all six European countries was 0.839 (95% CI 0.805, 0.873). The Hedge's g effect size for the difference in log odds of predicted probability between safe drinkers in Europe who subsequently developed hazardous alcohol use and those who did not was 1.38 (95% CI 1.25, 1.51). External validation of the algorithm in Chilean safe drinkers resulted in a c-index of 0.781 (95% CI 0.717, 0.846) and Hedge's g of 0.68 (95% CI 0.57, 0.78).
  
  
  CONCLUSIONS
  The predictAL risk model for development of hazardous consumption in safe drinkers compares favourably with risk algorithms for disorders in other medical settings and can be a useful first step in prevention of alcohol misuse.
authors.affiliation: Department of Mental Health Sciences, University College London, London, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: King
authors.forename: Louise
authors.initials: L
authors.lastname: Marston
authors.forename: Igor
authors.initials: I
authors.lastname: Švab
authors.forename: Heidi-Ingrid
authors.initials: HI
authors.lastname: Maaroos
authors.forename: Mirjam I
authors.initials: MI
authors.lastname: Geerlings
authors.forename: Miguel
authors.initials: M
authors.lastname: Xavier
authors.forename: Vicente
authors.initials: V
authors.lastname: Benjamin
authors.forename: Francisco
authors.initials: F
authors.lastname: Torres-Gonzalez
authors.forename: Juan Angel
authors.initials: JA
authors.lastname: Bellon-Saameno
authors.forename: Danica
authors.initials: D
authors.lastname: Rotar
authors.forename: Anu
authors.initials: A
authors.lastname: Aluoja
authors.forename: Sandra
authors.initials: S
authors.lastname: Saldivia
authors.forename: Bernardo
authors.initials: B
authors.lastname: Correa
authors.forename: Irwin
authors.initials: I
authors.lastname: Nazareth
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000453:epidemiology*; D000465:Algorithms; D002677:Chile / Q000453:epidemiology; D003617:Dangerous Behavior; D019992:Databases as Topic; D003710:Demography; D005060:Europe / Q000453:epidemiology; D005260:Female; D058006:General Practice / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015203:Reproducibility of Results; D012307:Risk Factors; D055815:Young Adult