The rapid digitalization of healthcare has heightened interest in Health Information Technology (HIT), with artificial intelligence (AI), the Internet of Things (IoT), and personal health records (PHR) emerging as transformative innovations. This study systematically reviews evidence from systematic reviews and meta-analyses published between 2016 and 2022 to evaluate the benefits of these technologies across clinical, psycho-behavioral, managerial, and socioeconomic domains. Twenty-four eligible studies were analyzed, revealing that AI consistently demonstrates superior diagnostic accuracy in several disease areas, improves treatment prediction, reduces medical errors, and lowers costs. IoT applications enhance real-time patient monitoring, streamline hospital workflow, and improve patient satisfaction, although challenges persist regarding availability, throughput, and data security. PHR adoption supports chronic disease management, strengthens preventive care, improves patient engagement and adherence, and reduces no-show rates, with moderate evidence for lowering healthcare utilization. Overall, the comparative synthesis highlights AI as a driver of clinical advancement, IoT as a facilitator of managerial efficiency, and PHR as a cornerstone of patient-centered care. Together, these technologies offer significant potential to improve healthcare outcomes, operational efficiency, and system sustainability. However, the existing evidence base is limited in scope and generalizability, emphasizing the need for large-scale, real-world studies to validate long-term impacts and guide policy, investment, and innovation in digital health.