WAYNE, NJInitial testing of the Symptom Experience Scale (SES),
designed to measure women's experiences of symptoms associated with
treatment for breast cancer, found six factors that used all 24 SES
items and accounted for 83% of the variance, report Nelda Samarel,
EdD, RN, of William Paterson College of New Jersey, and her colleagues.
The six factors were nausea and appetite, fatigue and sleep,
concentration, appearance, bowel pattern, and pain.
The SES is a modification of McCorkle's Symptom Distress Scale, which
was designed to measure symptoms of distress in patients with chronic
illness. The measurement of symptoms is important, Dr. Samarel says
(citing McCorkle) "to assess patients' needs, determine the
effectiveness of nursing interventions targeted to symptom
management, and assist patients in monitoring their own levels of health."
The SES measures the frequency, intensity, and distress of eight
symptoms (nausea, pain, appetite disturbance, sleep disturbance,
fatigue, changes in bowel pattern, concentration disturbance, and
changes in appearance), for a total of 24 items. It was tested in a
sample of 252 women with breast cancer.
Factor analysis was used to explore the underlying structure of the
symptom experience, Dr. Samarel says. The researchers expected to
find three factors, representing the three dimensions (frequency,
intensity, distress), for each symptom. However, a forced
three-factor solution produced conceptually confusing clusters of symptoms.
This led the team to seek a mathematical solution, which yielded six
clusters of symptoms (J Pain Symptom Manage 12:221-228, 1996). Rather
than the three dimensions, the actual factor structure was the
symptoms themselves, the authors note, with the dimensions of the
symptoms as components of each factor.
"These findings indicate that the three dimensions of the
symptom experience are equally important. By measuring all three
dimension, researchers and clinicians should be able to target
interventions to a specific aspect of a symptom or symptom
cluster," Dr. Samarel says.
The authors conclude that the SES is a useful instrument for
assessing symptoms associated with treatment for breast cancer, but
recommend further research to determine the stability of the
six-factor structure identified in their report.