In contrast to prior research that lacked a comprehensive analysis of a fundamental parameter, namely the average message delivery time (AMDT), this study significantly contributes to the academic community by offering cutting-edge insights into AMDT analysis for wireless healthcare monitoring in smart cities. Employing the innovative Narrowband Internet of Things (NB-IoT) technology, this article thoroughly investigates AMDT within wireless healthcare monitoring. The study focuses on analyzing AMDT during the transmission and reception of messages from base stations (BS) to remote healthcare data aggregators (HDAs) serving remote patients (RPs). Various vital parameters are considered, including modulation rate, average message length (AML), the average number of hops per path (H) required to reach remote patients, patient count, sub-carrier spacing (SS), and the modulation type within the communication range of the BS. This proposed assessment of health network performance offers a brief overview based on essential criteria, facilitating swift and precise evaluations of the efficacy of mobile health applications. The results obtained and the in-depth discussion of the outcomes of AMDT analysis provide valuable insights that can be harnessed to enhance the design and operation of wireless healthcare monitoring systems.