Abstract: Disclosed herein are novel assays, systems and kits for generating a personalized or stratified diagnostic report, e.g., to facilitate selection of an appropriate treatment of a musculoskeletal disease or disorder in a subject. The assays and systems are based on detecting and/or measuring in vitro anabolic responses of musculoskeletal cells or precursor cells thereof to a panel of test compositions (e.g., test compositions each comprising at least one agent selected to maintain and/or increase muscle and/or bone growth), and ranking the ability of each test composition to stimulate muscle and bone growth. The resultant ranks of the test compositions can then be used to identify, select, and/or optimize a treatment regimen for the subject who is determined to have, or have a risk, a musculoskeletal disease or disorder. Methods for treating and/or preventing a musculoskeletal disease or disorder are also provided herein.