Covariation of physical and mental symptoms across illnesses: results of a factor analytic study.
OBJECTIVE
Chronic illnesses are associated with reports of symptoms, problems, and dysfunction along multiple dimensions. To determine if the dimensionality is disease-specific and whether physical and emotional symptoms are concomitant and inseparable aspects of the illness experience, we present a factor analysis of symptom and problem reports from five different chronic conditions.


METHODS
People with five different conditions participated in this study: multiple sclerosis (MS) (n = 263), non-insulin-dependent diabetes mellitus (n = 420), nonhead nonneck injury trauma (n = 852), and a group of terminal patients comprised of acquired immune deficiency syndrome (AIDS) (n = 99) and cancer (n = 74) patients. Participants were asked to complete the Quality of Well-Being Scale (QWB) and symptom items from the QWB were factor analyzed.


RESULTS
Both within each condition and across conditions, two factors accounted for the majority of the explained variance and could be described as an Observable Limitations factor and a Subjective Symptoms factor.


CONCLUSIONS
Our factor analyses suggest that physical and emotional symptoms covary and are common to different types of illness.
Schwartz
C E
CE
Frontier Science & Technology Research Foundation, Inc., Chestnut Hill, MA 02467, USA.
Kaplan
R M
RM
Anderson
J P
JP
Holbrook
T
T
Genderson
M W
MW
D000163:Acquired Immunodeficiency Syndrome / Q000523:psychology*; D000328:Adult; D002170:Canada; D002908:Chronic Disease; D003924:Diabetes Mellitus, Type 2 / Q000523:psychology*; D005163:Factor Analysis, Statistical; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009103:Multiple Sclerosis / Q000523:psychology*; D009369:Neoplasms / Q000523:psychology*; D011795:Surveys and Questionnaires; D015599:Trauma Severity Indices; D014481:United States; D014947:Wounds and Injuries / Q000523:psychology*