Devices and methods for performing a point of care blood, cell, and/or pathogen count or a similar blood test. Disclosed herein are systems that can be used to provide rapid, accurate, affordable laboratory-quality testing at the point of care. The systems described herein are capable of imaging and counting individual cells in a prepared cell sample (e.g., a peripheral blood smear or a blood sample prepared in a microfluidic device) or another prepared cell- containing sample without the need for a microscope or other expensive and cumbersome optics. The systems described herein are designed to eliminate or replace expensive, centralized clinical testing equipment and technical personnel. Such systems may include automated data reporting and decision support.