Randomized controlled trials in ear, nose and throat surgery and neurosurgery: impact on healthcare practice in the Netherlands

Abstract

This thesis examines the impact of randomized controlled trials (RCTs) in otorhinolaryngology and neurosurgery on healthcare practice in the Netherlands, focusing on pediatric adenotonsillectomy and lumbar disc surgery for sciatica. It evaluates the influence of major trials—such as the NATAN, NOA, SPORT, and Sciatica trials—on clinical guidelines, healthcare utilization, and costs. The results show that new evidence led to decreased surgical rates and reduced regional variation, particularly in children with mild throat infections and patients with sciatica. For instance, tonsillectomy and adenoidectomy became less common in low-symptom cases following guideline updates, while sciatica treatment shifted toward shared decision-making and later surgery. Using national healthcare data, the thesis demonstrates measurable cost savings and improved alignment with evidence-based care. Additionally, it assesses how research impact is typically evaluated, showing that administrative healthcare data and long evaluation timeframes are key to capturing real-world effects. The findings underscore the importance of high-quality surgical research and structured implementation to reduce low-value care and promote effective treatment strategies.