Validity and reproducibility of two semi-quantitative alcohol frequency questionnaires for the Colombian population

Abstract

Objective: To determine the relative validity and reproducibility of two alcohol intake frequency questionnaires (AFQ-A; AFQ-B), designed to classify subjects according to their alcohol intake level, in Bucaramanga, Colombia. Method: One hundred and nine randomly selected subjects, aged between 20 and 60 years, completed three 30-day semi-quantitative alcohol intake records (30-DR). The AFQs were applied three months after the last 30-DR. AFQ-A contained 53 items; AFQ-B contained five items, with the alcoholic drinks for AFQ-B selected by Max_r. The correlation and agreement between alcohol intake assessed with the AFQs and the 30-DR were obtained using Pearson's correlation coefficient (r), Lin's concordance correlation coefficient (ρ C ), Spearman's rank correlation coefficient (r S ), Bland and Altman's limits of agreement (LOA) and Cohen's weighted kappa statistic (K W ). Results: The reproducibility of the 30-DR was poor; r S ranged from 0.33 to 0.41. The reproducibility of the AFQs was higher, with r S between 0.50 and 0.73. The agreement (K W ) of the 30-DR and the AFQs was 0.40. The lower and upper LOA were between -56.4% and -11.0%. The AFQs and 30-DR were well correlated. Assessment of relative validity between the two methods yielded r values for alcohol between 0.52 and 0.60, which reduced to 0.20-0.29 after energy adjustment. Conclusions: These AFQs may be useful to rank subjects according to their alcohol intake. The AFQ-B is easy and quick to apply, and is also highly cost-effective. © The Authors 2006.