CPTs

CPTs is an acronym that can refer to several concepts across fields. The most widely recognized are the medical coding system CPT, the professional credential Certified Personal Trainer, the probabilistic construct Conditional Probability Table, and in physics CPT symmetry.

Current Procedural Terminology (CPT) codes are a standardized system used in the United States to describe medical procedures and services. Maintained by the American Medical Association, CPT codes are used for billing and are often paired with ICD-10-CM diagnosis codes and HCPCS. They are categorized into Category I, II, and III; updates occur annually.

Certified Personal Trainer (CPT) is a professional credential indicating competency in exercise science, program design, safety, and client assessment. Certifications are offered by organizations such as the American Council on Exercise, the National Academy of Sports Medicine, and the American College of Sports Medicine. Requirements typically include passing an exam, maintaining CPR/AED certification, and completing continuing education units to renew the credential.

Conditional Probability Table (CPT) is a table that specifies the probability distribution of a random variable conditioned on its parent variables, used in Bayesian networks and other probabilistic models. Each row lists parent values and the corresponding conditional probabilities. CPTs must satisfy probability axioms, including non-negativity and that the probabilities sum to one.

CPT symmetry, or CPT invariance, refers to the combined transformation of charge conjugation, parity, and time reversal. The CPT theorem states that local, Lorentz-invariant quantum field theories are invariant under this transformation, making CPT symmetry a foundational principle in particle physics.