GLOSSARY

Screening Tool A standardized instrument used to identify possible risk within a defined population and setting.

Screening tools identify people who may need further nutrition assessment. Choose a validated tool for its intended population and setting, and follow its actual instructions rather than inventing a hybrid score. MUST, MNA and NRS-2002 have different purposes; SGA and PG-SGA involve broader assessment information. A positive result should lead to a suitable next step. A negative result does not override concerning symptoms, deteriorating function or a clinical history outside the tool's scope, especially when sport-specific underfueling is suspected.

Nutrition screening identifies people who may need fuller assessment; it does not establish every cause or prescribe treatment by itself. Use a suitable validated tool in the population for which it is intended, then follow a positive result with appropriate evaluation. Include recent intake, unintentional weight change, symptoms and clinical context. Repeat assessment when circumstances change. A negative screen is not a reason to ignore a new concerning symptom or a clear deterioration in the athlete's function.

Malnutrition can occur across body sizes, including in a person with obesity. Assessment considers reduced intake or assimilation, disease-related inflammation, weight trajectory and relevant body-composition or functional findings. Undernutrition, overnutrition and individual micronutrient deficiencies describe overlapping but distinct problems. A stable or high body weight cannot exclude inadequate nutrient supply or muscle loss. In an athlete, declining intake, recurrent illness or unintentional weight loss deserves assessment rather than automatic praise for becoming lighter.

For example, a positive screen should lead to an agreed assessment or referral with a responsible professional. Document what prompted the concern and what happens next. A screening score is useful only when its population and purpose fit; it should not be used to clear an athlete whose symptoms remain unexplained.