Translation, cultural adaptation assessment, and both validity and reliability testing of the kidney disease quality of life - short form version 1.3 for use with Iranian patients

TY - JOUR

T1 - Translation, cultural adaptation assessment, and both validity and reliability testing of the kidney disease quality of life - short form version 1.3 for use with Iranian patients

AU - Pakpour, Amir

AU - Yekaninejad, Mirsaeed

AU - Mølsted, Stig

AU - Harrison, Adrian Paul

AU - Hashemi, Fariba

AU - Saffari, Mohsen

PY - 2011/1

Y1 - 2011/1

N2 - Aim: The aims of the study were to translate the Kidney Disease Quality of Life - Short Form version 1.3 (KDQOL-SF ver. 1.3) questionnaire into Iranian (Farsi), and to then assess it in terms of validity and reliability on Iranian patients. Methods: The questionnaire was first translated into Farsi by two independent translators, and then subsequently translated back into English. After translation disparities had been reconciled, the final Iranian questionnaire was tested. An initial test-retest reliability evaluation was performed over a 10 day period on a sample of 20 patients recruited from a larger group (212 patients with end-stage renal disease on haemodialysis). Afterwards, reliability was estimated by internal consistency, and validity was assessed using known group comparisons and constructs for the patient group as a whole. Finally, the factor structure of the questionnaire was extracted by performing exploratory factor analysis. Results: All of the scales in the questionnaire showed good test-retest reliability (i.e. intraclass correlations between test and retest scores were >0.7). All of the scales met the minimal criteria (0.7) for internal consistency and Cronbach's-α ranged 0.71-0.93. Furthermore, results from a discriminate validity evaluation showed that the questionnaire could be used to discriminate between subgroups of the patients. Finally, a principal component analysis of the disease-specific scales indicated that this part of the questionnaire could be summarized into an 11 factor structure that jointly accounted for 79.81% of the variance. Conclusion: The Iranian version of the KDQOL-SF questionnaire is both highly reliable and valid for use with Iranian patients on haemodialysis. This paper addresses the issue of quality of life in patients with kidney failure describing the process of translating the well-known KDQOL into Iranian.

AB - Aim: The aims of the study were to translate the Kidney Disease Quality of Life - Short Form version 1.3 (KDQOL-SF ver. 1.3) questionnaire into Iranian (Farsi), and to then assess it in terms of validity and reliability on Iranian patients. Methods: The questionnaire was first translated into Farsi by two independent translators, and then subsequently translated back into English. After translation disparities had been reconciled, the final Iranian questionnaire was tested. An initial test-retest reliability evaluation was performed over a 10 day period on a sample of 20 patients recruited from a larger group (212 patients with end-stage renal disease on haemodialysis). Afterwards, reliability was estimated by internal consistency, and validity was assessed using known group comparisons and constructs for the patient group as a whole. Finally, the factor structure of the questionnaire was extracted by performing exploratory factor analysis. Results: All of the scales in the questionnaire showed good test-retest reliability (i.e. intraclass correlations between test and retest scores were >0.7). All of the scales met the minimal criteria (0.7) for internal consistency and Cronbach's-α ranged 0.71-0.93. Furthermore, results from a discriminate validity evaluation showed that the questionnaire could be used to discriminate between subgroups of the patients. Finally, a principal component analysis of the disease-specific scales indicated that this part of the questionnaire could be summarized into an 11 factor structure that jointly accounted for 79.81% of the variance. Conclusion: The Iranian version of the KDQOL-SF questionnaire is both highly reliable and valid for use with Iranian patients on haemodialysis. This paper addresses the issue of quality of life in patients with kidney failure describing the process of translating the well-known KDQOL into Iranian.

KW - Former LIFE faculty

KW - end-stage renal disease

KW - health related quality of life

KW - haemodialysis

KW - Kidney Disease Quality of Life - Short Form

KW - psychometric evaluation

U2 - 10.1111/j.1440-1797.2010.01389.x

DO - 10.1111/j.1440-1797.2010.01389.x

M3 - Journal article

C2 - 21175986

SN - 1320-5358

VL - 16

SP - 106

EP - 112

JO - Nephrology

JF - Nephrology

IS - 1

ER -