Inclusion Criteria:

Age of 18+ years, able and willing to sign the consent form, inpatients of the Tartu University Hospital, admitted within 72 hours before enrolment.

Exclusion Criteria:

Age of <18 years, inability or refusal to sign the consent form, pregnant or lactating women, more than 72 hours passed since admission, patients isolating with an infection.

The patient is interviewed for changes in body weight in the last six months and food intake in the last two weeks.

The investigator evaluates the patient's diet, symptoms related to their nutritional status, and functional capacity according to the Subjective Global Assessment (SGA). The SGA tool itself is completed by the researcher.

Height and weight of the patient are measured, if not yet recorded, and BMI is calculated.

The patient's muscle mass is measured using mid-upper arm circumference (MUAC), calf circumference (CC) and bioelectrical impedance (BIA), and their muscle function assessed using hand grip strength.

Subjective Global Assessment (SGA) can be considered a method that is close to a "gold standard" for malnutrition assessment. Therefore, the study will analyse how different approaches to screening and muscle mass measurement affect the performance of GLIM in detecting Subjective Global Assessment (SGA) defined malnutrition.

One year after the data collection, we will look at the patient records to collect the 1-year mortality data. This will give information about whether and how different approaches to components of GLIM affect its ability to predict one-year mortality.

One of the GLIM criteria is "reduced muscle mass", and this study will investigate how muscle mass measured with simpler methods compares against muscle mass measured with CT.

One of the GLIM criteria is "reduced muscle mass", and this study will investigate how muscle mass measured with simpler methods compares against muscle mass measured with DEXA.

One of the GLIM criteria is "reduced muscle mass", and this study will investigate how muscle mass measured with simpler methods compares against muscle mass measured with BIA.