A Revised Version of Diabetes Quality of Life Instrument Maintaining Domains for Satisfaction, Impact, and Worry
Table 4
Item fit statistics of the simplified/revised DQoL from Rasch analysis.
Domain
Item
Point measure correlation
Infit MNSQ (ZStd)
Outfit MNSQ (ZStd)
Satisfaction
(S1) Time takes to manage diabetes
0.84
0.97 (−0.4)
0.96 (−0.5)
(S2) Time spend getting checkups
0.85
0.78 (−3.4)
0.70 (−4.2)
(S3) Time it takes to determine the sugar level
0.85
0.91 (−1.3)
0.90 (−1.4)
(S4) Current treatment
0.84
0.90 (−1.5)
0.81 (−2.6)
(S7) Knowledge about diabetes
0.81
1.23 (3.1)
1.25 (3.3)
(S15) Life in general
0.81
1.21 (2.9)
1.23 (2.9)
Impact
(I1) Feel pain associated with the treatment
0.76
1.05 (0.8)
1.04 (0.6)
(I4) Feel physically ill
0.80
0.87 (−1.9)
0.88 (−1.8)
(I5) Interfere with the family life
0.79
0.95 (−0.7)
0.91 (−1.2)
(I7) Limiting social relationships and friendships
0.70
1.20 (2.6)
1.07 (0.8)
Worry
(W8) Pass out
0.74
1.27 (3.3)
1.22 (2.7)
(W9) Body looks differently
0.84
0.83 (−2.4)
0.81 (−2.8)
(W10) Get complications
0.87
0.92 (−1.1)
0.91 (−1.3)
MNSQ: mean square; ZStd: standardized fit statistic. Point measure correlation within 0.40 and 0.85 suggests that the items are interrelated within the domain. MNSQ range of 0.5 to 1.5 and ZStd of ±2.0 suggests an acceptable fit.
