2.4 Risk status assessment
The Traffic Light model (Grabkowsky, 2009; Alhaji et al., 2018) was used to assess risk status of AMU in beef cattle farms. The model works on the premise of three risk levels: High risk (Class 3) represented by red; Medium risk (Class 2) by yellow; and Low risk (Class 1) by green. The assessment was based on the following assumptions: proportions of farms in which antimicrobials were used “without” veterinarians’ consultations were considered to be in Class 3 (Red or High risk) status; while proportions of farms in which antimicrobials were used “with irregular” veterinarians’ consultations were considered to be in Class 2 (Yellow or Medium risk) status. However, proportions of farms in which antimicrobials were used always with veterinarians’ consultations were in Class 3 (Green or Low risk) status. All proportions were determined at 95% confidence level.