12.5 Nutrition Diagnosis, PES Statements & the NCP

The Nutrition Care Process

The Nutrition Care Process (NCP) standardizes dietetics practice in four steps, remembered through the documentation acronym ADIME: Assessment, Nutrition Diagnosis, Intervention, and Monitoring/Evaluation. The nutrition diagnosis is the step unique to the RDN — physicians make medical diagnoses, but identifying and naming the nutrition problem is the dietitian's professional responsibility and scope. A clear diagnosis drives everything downstream: the intervention targets the etiology, and monitoring re-measures the signs and symptoms.

Nutrition Diagnosis vs. Medical Diagnosis

A medical diagnosis (cystic fibrosis, celiac disease, anorexia nervosa) is made by a physician and managed medically. A nutrition diagnosis names a nutrition problem the RDN can independently identify and treat — for example, inadequate energy intake, impaired nutrient utilization, or swallowing difficulty. A child with cystic fibrosis carries the medical diagnosis of CF; the RDN diagnoses the nutrition problems that flow from it, such as inadequate energy intake or impaired nutrient utilization.

PES Statement Structure

The nutrition diagnosis is written as a PES statement — three components joined by standardized connecting phrases:

Problem (P) related to Etiology (E) as evidenced by Signs/Symptoms (S).

Worked example: "Inadequate energy intake related to increased energy needs secondary to cystic fibrosis as evidenced by BMI z-score decline from −0.5 to −1.8 over 6 months and reported intake meeting only ~75% of estimated needs."

• Problem: a standardized NCP terminology term describing an alteration in nutrition status. Write one problem per statement.
• Etiology: the root cause or contributing factor — choose a cause the RDN can address or resolve through nutrition intervention. Do not use a medical diagnosis alone as the etiology; name the nutrition consequence of the disease instead ("increased needs secondary to CF", "malabsorption").
• Signs/Symptoms: specific, measurable evidence from the assessment — growth data, intake records, laboratory values, NFPE findings — that proves the problem exists now and doubles as the monitoring indicators.

Terminology Domains (Pediatric-Relevant)

NCP terminology organizes problems into three domains:

• Intake domain: too much or too little taken in — inadequate or excessive energy intake, inadequate protein, fluid, or nutrient intake, inappropriate infusion of enteral or parenteral nutrition.
• Clinical domain: problems inside the body — impaired nutrient utilization, altered GI function, swallowing difficulty, altered nutrition-related laboratory values, underweight and growth faltering.
• Behavioral-environmental domain: knowledge, beliefs, and access — limited food access, disordered eating patterns, undesirable food choices, and caregiver knowledge deficit or impaired ability to prepare appropriate foods.

Prioritization

Children often have more than one nutrition diagnosis at once. Prioritize by severity and safety (refeeding risk outranks picky eating), by which problem is most central to the growth or clinical outcome, and by what the intervention can realistically change first. Document the diagnosis selected for intervention and the criteria used to prioritize it.

Linking Diagnosis → Intervention → Monitoring

The NCP is a chain: the intervention must target the etiology, and monitoring must re-measure the signs/symptoms. If the PES cites a BMI z-score decline and intake at 75% of needs, the monitoring plan schedules weight, BMI z-score, and intake re-assessment; if it cites ferritin, the plan repeats ferritin. Mapping each PES to measurable goals and outcomes is a frequent exam concept.

Documentation and Coding

• ICD-10-CM codes document medical diagnoses, including the malnutrition codes in the E40-E46 range, which carry severity specificity (moderate vs. severe protein-calorie malnutrition); NFPE and anthropometric criteria supply the documentation that supports severity coding.
• CPT codes for Medical Nutrition Therapy (MNT): 97802 (initial assessment and intervention, per 15 minutes) and 97803 (re-assessment and follow-up, per 15 minutes); 97804 covers group MNT.
• Billing basics: MNT coverage varies by payer and diagnosis, so accurate documentation of the PES statement and outcomes supports reimbursement.

Common PES Errors and Exam Traps

• Using a medical diagnosis as the etiology ("related to cystic fibrosis" instead of "related to increased needs secondary to cystic fibrosis").
• Cramming two problems into one statement.
• Vague or non-measurable signs/symptoms ("as evidenced by poor growth" instead of quantified z-scores with a timeframe).
• Choosing an etiology the RDN cannot influence (genetics, surgical anatomy).
• Confusing the nutrition diagnosis with the medical diagnosis, or writing a problem statement for a risk when no problem currently exists.

Worked Examples

Each example follows the same pattern: one problem, an etiology within the RDN's reach, and measurable signs/symptoms that become the monitoring indicators.