Japanese version of the Dermatology Life Quality Index: validity and reliability in patients with acne.
BACKGROUND
Patient-reported quality of life is strongly affected by some dermatologic conditions. We developed a Japanese version of the Dermatology Life Quality Index (DLQI-J) and used psychometric methods to examine its validity and reliability.


METHODS
The Japanese version of the DLQI was created from the original (English) version, using a standard method. The DLQI-J was then completed by 197 people, to examine its validity and reliability. Some participants completed the DLQI-J a second time, 3 days later, to examine the reproducibility of their responses. In addition to the DLQI-J, the participants completed parts of the SF-36 and gave data on their demographic and clinical characteristics. Their physicians provided information on the location and clinical severity of the skin disease.


RESULTS
The participants reported no difficulties in answering the DLQI-J items. Their mean age was 24.8 years, 77.2% were female, and 78.7% had acne vulgaris. The mean score of DLQI was 3.99(SD: 3.99). The responses were found to be reproducible and stable. Results of principal-component and factor analysis suggested that this scale measured one construct. The correlations of DLQI-J scores with sex or age were very poor, but those with SF-36 scores and with clinical severity were high.


CONCLUSIONS
The DLQI-J provides valid and reliable data despite having only a small number of items.
Takahashi
Natsuko
N
Institute for Health Outcomes and Process Evaluation Research, Tokyo, Japan. n-takahashi@jcqhc.or.jp
Suzukamo
Yoshimi
Y
Nakamura
Motonobu
M
Miyachi
Yoshiki
Y
Green
Joseph
J
Ohya
Yukihiro
Y
Finlay
Andrew Y
AY
Fukuhara
Shunichi
S
D000152:Acne Vulgaris / Q000145:classification / Q000503:physiopathology / Q000523:psychology*; D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D007564:Japan; D007802:Language; D008297:Male; D010865:Pilot Projects; D011594:Psychometrics / Q000295:instrumentation*; D011788:Quality of Life; D012574:Schools; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D009626:Terminology as Topic; D014177:Translations; D017132:Workplace / Q000523:psychology