Objective According to a previous study, 17% of patients who attended an emergency department (ED) following cocaine use returned to the same ED over the next year for a problem related to drug use. This previous study proposed a scale (Multicenter Assessment of the Revisit Risk In the Emergency Department (MARRIED)-cocaine score) to quantify the risk of ED revisit. The aim of the present study was to validate this scale by analysing a new set of patients attending for cocaine use in nine Spanish EDs.

Methods We performed a retrospective, multicentre, cohort study with consecutive patient inclusion, and without an intervention or control group. During 12 months (January–December 2010) we collected data from patients attending the ED after cocaine use. The MARRIED-cocaine score, ranging from 0 to 400 points, was calculated for each patient. The dependent variable was the identification of further visits associated with drug consumption to the same ED. Further analysis was performed to define risk categories.

Results The study included 933 patients, with a mean follow-up of 466 (SD 189) days, and 185 patients returned to the same ED for problems related to drug consumption. The cumulative probability of ED revisit was 4.2%, 8.3%, 16.8% and 21.2% at 1 month, 3 months, 12 months and 24 months, respectively. The area under the curve receiver operating characteristic for the MARRIED-cocaine scale was 0.69 (p<0.001). Four categories for ED revisit risk were defined: low risk (0–40 points, n=416), moderate risk (41–100 points, n=235), high risk (101–210 points, n=71) and very high risk (210–400 points, n=211), with HRs for ED revisit (with respect to the low-risk group) of 1.82 (95% CI 1.18 to 2.80, p=0.007), 2.65 (95% CI 1.50 to 4.66, p=0.001) and 5.06 (95% CI 3.49 to 7.35, p<0.001), respectively.

Conclusions The MARRIED-cocaine score has a moderate discriminative capacity to predict revisit among patients who attend the ED for cocaine drug-related emergencies, and allows classification of patients according to the risk of ED revisit.