Nausea is one of the most distressing human symptoms. In cancer patients, nausea is associated with noncompliance with the chemotherapy regimen and decreased quality of life.

The purpose of this descriptive exploratory study was to examine the validity of a proposed nursing diagnosis, alteration in comfort, nausea as it occurs in chemotherapy patients. This multiphasic study combined the use of the Delphi technique, test-retest reliability, magnitude estimation scaling (MES), and clinical observation to explicate critical defining characteristics, important defining characteristics, and clinical manifestations for the diagnosis under study.

Phase I involved the use of a Delphi panel of nurse experts to identify a list of defining characteristics which were appropriate to explicate the diagnosis. In Phase II, MES was utilized to identify critical and important defining characteristics as well as clinical manifestations and the frequency of occurrence of these defining characteristics. Four defining characteristics, gagging sensation, stomach cramps, sour stomach, and sour taste in mouth, fell into the upper quartile for importance. These four defining characteristics plus increase in oral secretions fell into the upper quartile for frequency. In Phase III, a sample of 60 patients receiving chemotherapy was divided into two groups, those who experienced nausea with chemotherapy and those who did not.

A test of discriminant analysis revealed that the critical defining characteristics significantly discriminated between the two groups (F = 15.68, R$sp2$ =.5327, p =.0001) indicating that these critical defining characteristics must be present to confirm the diagnosis under study.

Recommendations based on the conclusions of this study include the introduction of critical thinking and problem solving exercises early in the nursing programs to facilitate development of diagnostic abilities in the student nurse. The Nausea Measurement Index would be helpful to assist nurses in practice to identify cues which could be coalesced to facilitate hypothesis activation for patients. Standards of care for oncology clients could reflect the defining characteristics and provide an outline for the nurse to assess patients who are taking chemotherapy. Moreover, accurate assessment by nurses would provide a basis for hypothesis evaluation necessary for on-going plans of care.