This literature review by a research group from Australia explored various methods used for selecting cancer patients for proton versus X-ray radiation therapy. Within the 49 articles included for analysis, six different clinical decision-making tools and 14 dose comparison methods were identified. The most commonly reported patient selection tools included the Normal Tissue Complication Probability model, followed by cost-effectiveness modelling and dosimetry comparison. Model-based selection methods were most commonly applied for head and neck clinical indications in adult cohorts. PT patient selection was clear and consistent for pediatric patients across all clinical indication lists, whereas PT patient selection was variable for adult patients. Many NTCP endpoints reported are only valid for X-rays and have not yet been validated in protons. Caution must be taken in plan comparison if inherent uncertainties of proton is considered and PT plans are robustly optimized.