Cost-effectiveness and cost-utility of a digital technology-driven hierarchical healthcare screening pattern in China.

Utilization of digital technologies for cataract screening in primary care is a potential solution for addressing the dilemma between the growing aging population and unequally distributed resources. Here, we propose a digital technology-driven hierarchical screening (DH screening) pattern implemented in China to promote the equity and accessibility of healthcare. It consists of home-based mobile artificial intelligence (AI) screening, community-based AI diagnosis, and referral to hospitals. We utilize decision-analytic Markov models to evaluate the cost-effectiveness and cost-utility of different cataract screening strategies (no screening, telescreening, AI screening and DH screening). A simulated cohort of 100,000 individuals from age 50 is built through a total of 30 1-year Markov cycles. The primary outcomes are incremental cost-effectiveness ratio and incremental cost-utility ratio. The results show that DH screening dominates no screening, telescreening and AI screening in urban and rural China. Annual DH screening emerges as the most economically effective strategy with 341 (338 to 344) and 1326 (1312 to 1340) years of blindness avoided compared with telescreening, and 37 (35 to 39) and 140 (131 to 148) years compared with AI screening in urban and rural settings, respectively. The findings remain robust across all sensitivity analyses conducted. Here, we report that DH screening is cost-effective in urban and rural China, and the annual screening proves to be the most cost-effective option, providing an economic rationale for policymakers promoting public eye health in low- and middle-income countries.

Optical polarization division multiplexing fiber-wireless integration system at Ka-band based on a low-cost dual-drive MZM.

In this paper, a low-cost dual-drive Mach-Zehnder modulator (DDMZM) based 40 Gbit/s polarization division multiplexing (PDM) fiber-wireless-integration system at Ka-band is experimentally demonstrated. Since the DDMZM is biased at the quadrature point for electro-to-optical (E/O) conversion, a high-power direct current (DC)/radio frequency (RF) component will appear within the received signal bandwidth. This high-power component becomes a narrowband interference due to the phase noise of lasers, which will lead to the incorrect convergence of the constant-modulus algorithm (CMA) during equalization at the receiver side. In order to deal with the broadened DC component, twin-single-sideband (twin-SSB) signal with bandwidth interleave and RF-pilot based phase noise compensation scheme are adopted. Enabled by the combination of optical PDM technique and heterodyne coherent detection, a 40 Gbit/s PDM twin-SSB Nyquist-shaped quadrature-phase-shift-keying (QPSK) signal transmitting over 20-km single mode fiber (SMF) and 1-m 2×2 multiple-input multiple-output (MIMO) wireless distance is achieved with the bit error rate (BER) below the hard-decision forward-error-correction (HD-FEC) threshold of 3.8×10-3.

Cost-efficient half-duplex 10 Gbit/s all-optical indoor optical wireless communication enabled by a low-cost Fabry-Perot laser/photodetector.

To develop an indoor optical wireless communication (OWC) system, both the system complexity/cost and data rate need to be taken into consideration. In this Letter, a cost-efficient half-duplex OWC system for photonic home area network applications is proposed and experimentally demonstrated. A low-cost Fabry-Perot laser diode is proposed to be employed as both the downlink receiver (Rx) and uplink transmitter at the user side. Enabled by the Fabry-Perot transceiver, the indoor transmission of 10 Gbit/s four-level pulse-amplitude-modulation signal for both downlinks and uplinks is experimentally achieved over a 1.7 km single-mode fiber and 1.1 m free space. Moreover, the proposed scheme also enables us to operate an orthogonal frequency division multiplexing (OFDM) signal. The bit error rate levels of multi-gigabit OFDM data for both downlinks and uplinks over a 10 h measurements are all under a 7% forward error correction limit of 3.8×10-3, which indicates that the proposed system is robust and, thus, can provide a promising solution for high-speed low-cost home area OWC networks.