Reliability and validity of the Japanese version of the pelvic floor distress inventory-short form 20.
OBJECTIVE
The aim of this study was to translate the Pelvic Floor Distress Inventory-Short Form 20 (PFDI-20) into Japanese and test its reliability and validity among Japanese women.


METHODS
Fifty-nine women with and without pelvic floor disorders (age 55.8 ± 16.8 years, mean ± SD) completed the Japanese PFDI-20 (J-PFDI-20) questionnaire at baseline and 2 weeks later. Intraclass correlation coefficients (ICC) and the Bland and Altman method for test-retest reliability and Cronbach's alpha for internal consistency of the J-PFDI-20 were used. Scores of total and subscales were compared between women with and without pelvic floor disorders for known-groups validity. Spearman's correlation coefficients between the J-PFDI-20 and the severity of pelvic floor disorders and Urinary Incontinence Quality of Life Scale (I-QOL) were used for construct validity.


RESULTS
The PFDI-20 was successfully translated from English into Japanese with face validity through rigorous cross-cultural validation. Test-retest reliability of the J-PFDI-20 and three subscales was good to excellent (ICC=0.77-0.90). The Bland and Altman analysis showed that differences between the first and second scores of total J-PFDI-20 and its subscales were not significantly different from 0 and largely fell within the range of 0 ± 1.96 SD. Cronbach's alpha values were 0.52-0.83. Analysis of known-groups validity showed differences in scores of the J-PFDI-20 between women with and without pelvic floor disorders. Acceptable construct validity was found in J-PFDI-20 total and subscale scores with positive correlations to severity of pelvic floor disorders (ρ>0.35) and negative correlations to I-QOL (ρ<-0.39).


CONCLUSIONS
The results suggest that the J-PFDI-20 is a reliable and valid condition-specific quality of life instrument for women with pelvic floor disorders.
Department of Gerontological Nursing/Wound Care Management, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. mokka-tky@umin.ac.jp
Mikako
M
Yoshida
Ryoko
R
Murayama
Erika
E
Ota
Maki
M
Nakata
Shiro
S
Kozuma
Yukio
Y
Homma
D000328:Adult; D000368:Aged; D044466:Asian People; D003469:Culture; D005242:Fecal Incontinence / Q000209:etiology / Q000523:psychology; D005260:Female; D006801:Humans; D007802:Language; D008875:Middle Aged; D059952:Pelvic Floor Disorders / Q000150:complications / Q000523:psychology*; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D014175:Translating; D014549:Urinary Incontinence / Q000209:etiology / Q000523:psychology