Situation: A 40-year-old woman is admitted to the psychiatric ward with major depressive disorder. She has lost 3 kg in 4 weeks, eats about half of each meal, sleeps 3 to 4 hours a night, and says worrying thoughts keep her awake at bedtime. Her vital signs are within normal limits. The nurse writes nursing diagnoses using NANDA International (NANDA-I) 2024–2026 labels. The nurse reviews diagnostic statements that a student wrote for this client. Which statement is written correctly?

A problem-focused statement links a NANDA-I label to a cause nurses can treat ("related to") and to the client's signs and symptoms ("as evidenced by"). Common errors are using a medical diagnosis as the cause, writing a need or intervention as the problem, and restating the problem as its own cause.

Understanding the NANDA-I diagnostic statement structure

A correctly written problem-focused nursing diagnosis has three linked parts: the NANDA-I diagnostic label, the related to (r/t) factor that nurses can address, and the as evidenced by (AEB) signs or symptoms observed in the client. The diagnostic label names the human response, the related factor identifies the etiology or contributing condition, and the evidence grounds the diagnosis in objective or subjective data.

The related factor must be a condition that nursing interventions can modify or influence, not a medical diagnosis or a restatement of the problem itself. When the etiology is a medical disease, the nurse cannot treat the disease directly; instead, the nurse addresses the client's response to that disease. Similarly, writing the problem as its own cause creates a circular statement that provides no direction for care.

Analyzing each diagnostic statement

Option	Diagnostic label	Related factor	Evidence	Problem
1	Inadequate nutritional intake	Major depressive disorder	3-kg loss in 4 weeks	Medical diagnosis used as etiology; nurses cannot treat the disease itself
2	Needs encouragement to eat	Low appetite	Eating half of each meal	Problem is written as a nursing intervention, not a NANDA-I label
3	Maladaptive coping	Inability to cope with stress	Staying in bed most of the day	Circular statement; the cause restates the problem
4	Ineffective sleep pattern	Worrying thoughts at bedtime	Sleeping 3 to 4 hours nightly	Correct: modifiable factor, observable evidence, valid label

Watch out! Option 1 fails because major depressive disorder is a medical diagnosis. The nurse treats the client's response to depression, not the depression itself. A more appropriate related factor would be something like decreased appetite secondary to depressed mood or psychomotor retardation, which nursing interventions can address.

Watch out! Option 2 uses "needs encouragement to eat" as the diagnostic label. This is a nursing intervention or a goal, not a NANDA-I human response label. The correct label would be Imbalanced nutrition: less than body requirements or Inadequate nutritional intake.

Watch out! Option 3 is circular: "Maladaptive coping related to an inability to cope with stress" simply restates the problem as its own cause. The related factor should identify what is contributing to the maladaptive coping, such as inadequate support system or negative self-appraisal.

Why option 4 is correct

Option 4 follows the complete three-part structure. The label Ineffective sleep pattern is a recognized NANDA-I diagnosis describing a disruption in sleep quantity or quality. The related factor worrying thoughts at bedtime is a condition nurses can address through interventions such as relaxation techniques, cognitive reframing, sleep hygiene education, or scheduled worry time. The evidence sleeping 3 to 4 hours nightly is objective, measurable data that supports the diagnosis. This statement gives clear direction for planning care because the nurse knows what to target: the bedtime rumination that interferes with sleep onset.

Clinical application of standardized nursing language

The use of NANDA-I, NOC, and NIC taxonomies supports consistency and clarity in care planning. When diagnostic statements are written correctly, they guide the selection of appropriate outcomes and interventions. A well-formed diagnosis such as Ineffective sleep pattern related to worrying thoughts at bedtime as evidenced by sleeping 3 to 4 hours nightly allows the nurse to choose outcomes like improved sleep duration and interventions like teaching progressive muscle relaxation or limiting stimulating activity before bed. Conversely, poorly written statements with medical etiologies or circular logic create ambiguity and hinder the nursing process.

The quality of a nursing diagnosis depends on selecting a valid NANDA-I label, identifying a modifiable related factor, and providing observable evidence that links the label to the client's actual presentation. This three-part linkage is what makes the nursing process clinically meaningful and actionable.