Rosenthal BD, et al. - Researchers categorized adult subjects who had spine surgery in 3 groups and studied to evaluate the risk factors for prolonged postoperative opioid use after spine surgery by using statistical analysis including multivariate modified Poisson regression, linear regression, and chi-squared testing. They recognized the use of opioid medications at 6 months preoperatively as a risk factor for continued usage and at higher doses 6 months postoperatively after excluding determinants like psychiatric history, smoking status, and alcohol use etc.