Assessment and Nutrition Diagnosis
Core concepts
The nutrition care process begins with assessment across domains: anthropometric, biochemical, clinical, dietary, and food-nutrition history. Know how to interpret body mass index, weight change percentage, triceps skinfold, and mid-arm circumference, plus biochemical markers such as albumin, prealbumin, transferrin, and inflammatory markers like CRP, which confound protein status interpretation. Understand 24-hour recall, food frequency questionnaires, and food records, including their strengths and recall bias limitations. Recognize malnutrition screening tools and the standardized language of nutrition diagnosis: problem (P), etiology (E), and signs/symptoms (S). A diagnosis statement links a problem to its cause and evidence, for example "Inadequate protein-energy intake related to dysphagia as evidenced by 5% weight loss in one month."
Traps
Questions frequently confuse a nutrition diagnosis with a medical diagnosis or with an intervention. Another trap is treating low albumin as proof of malnutrition when inflammation may be the driver. Watch for items that misattribute a PES statement component, such as placing the cause in the signs/symptoms slot. Also beware of questions that ask for the most appropriate screening tool without matching the population.
Worked example
A patient weighed 80 kg three months ago and now weighs 72 kg. Weight change = (80-72)/80 x 100 = 10% loss, which is clinically significant and warrants nutrition diagnosis and intervention. Rule of thumb: always divide by the usual or previous weight, not the current weight, and document the timeframe.