Statistical analysis
Descriptive statistics were used to analyse the individuals’ characteristics and the antibiotic-resistance patterns of the staphylococci isolated. The prevalence of the resistance rates and the number of boxes of the different antibiotics prescribed in the previous 4 years were calculated. To evaluate the association of the previous number of boxes dispensed and the staphylococcal resistance patterns, a multivariate logistic regression analysis model was constructed with resistance of isolated S. aureus strain as the dependent variable and considering age, sex and number of boxes of the different antibiotics prescribed (according to the Anatomical Therapeutic Chemical Classification System) in the prior 4 years as independent variables. Adjusted odds ratios (ORs) with their 95% confidence interval (95% CI) were estimated. Antibiotics evaluated were penicillin, oxacillin, erythromycin, azithromycin, clindamycin, ciprofloxacin, gentamicin, tetracycline, vancomycin, linezolid and daptomycin. Differences were considered to be significant with P < 0.05.
The study was approved by the Research Ethics Committee IDIAP Jordi Gol Clinic (P10/55), and each participant voluntarily signed the informed consent. In the case of minors, the father or mother or legal guardian was the one who signed it.
Anonymity guaranteed and confidentiality, as well as the protection of data.