Oscar F Herrán1, María F Ardila. 1. Centro de Investigaciones Epidemiológicas, Observatorio Epidemiológico de Enfermedades Cardiovasculares, Universidad Industrial de Santander, Bucaramanga, Colombia. herran28@intercable.net.co
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 (rhoC), Spearman's rank correlation coefficient (rS), Bland and Altman's limits of agreement (LOA) and Cohen's weighted kappa statistic (Kw). RESULTS: The reproducibility of the 30-DR was poor; rS ranged from 0.33 to 0.41. The reproducibility of the AFQs was higher, with rS between 0.50 and 0.73. The agreement (Kw) 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.
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 (rhoC), Spearman's rank correlation coefficient (rS), Bland and Altman's limits of agreement (LOA) and Cohen's weighted kappa statistic (Kw). RESULTS: The reproducibility of the 30-DR was poor; rS ranged from 0.33 to 0.41. The reproducibility of the AFQs was higher, with rS between 0.50 and 0.73. The agreement (Kw) 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.