Background: We present data comparing the quality of life effects of
type 2 diabetes determined by the Bradley well-being questionnaire and
the WHOQOL-BREF, a generic instrument. We also present data on the
reliability and validity of these instruments. Method: The Well-being
and the WHO- bref were administered on fifty-three consecutive type 2
diabetics. The internal consistency of the quality of life scales was
assessed using Cronbach's alpha. Convergent, discriminant, and known
groups validity were determined and compared. Results: Our patients
had a mean age of 55.8±13 years. 31(58.5%) were males and all
patients had been diabetic for 7.9±7.1 years. 13(24.5%) were being
treated with oral agents, 14(26.4%) were on insulin and 26(49.1%) were
on combined therapy. The Cronbach alpha coefficients ranged from 0.31
to 0.72 on the Well-being subscales and from 0.47 to 0.78 on the
WHOQOL-BREF subscales. Both scales were modestly related to one
another. In general the quality of life measures were not influenced by
characteristics such as age, gender, marital or educational status.
Both scales were not influenced significantly by treatment type or the
severity or number of complications. Conclusion: Our study has shown
how two different measures of quality of life perform in patients with
type 2 diabetes. Even though the subscales of the Well-being and
WHOQOL-BREF were not very sensitive to external criteria of disease
impact (complications) casting a doubt on their utility as
psychological outcome measures, they demonstrated fairly reasonable
internal consistency in our patients with type 2 diabetes. Further
larger studies are thus required to clarify this given our present
limitations