An approach to cultural adaptation and validation: the Intermittent Claudication Questionnaire

Abstract

The objective of this study was to perform a cultural adaptation and define the validity of the Turkish version of the Intermittent Claudication Questionnaire (ICQ) in order to provide a practical instrument for the evaluation of the impact of intermittent claudication (IC) on patients' quality of life and response to therapy. A standard 'forward-backward' translation method was used to translate the questionnaire into Turkish. Reliability was assessed by internal consistency of the questionnaire reporting Cronbach's α coefficient, test-retest reliability that was assessed with the intraclass correlation between instrument scores over time and with the Spearman-Brown coefficient as a variant of split-half reliability. Validity was examined by correlation of the ICQ with the scores of the SF-36 and its eight domains. Eighty-four patients (mean age, 60.7 ± 7.3 years; male, 57%) were given the ICQ and a final completion rate of 98.8% (83 patients) was reached. The mean total ICQ score was 39.1 ± 21.8 (SD) (0-100) for the first application of the questionnaire. Thirty patients out of the eligible 83 completed the questionnaire at two time points with a 1-day interval. For the retest, the total ICQ score was 40.6 ± 26.1 (4.7-97.2). The total SF-36 score of all the study patients was 33.8 ± 20.7 (3.0-81.0). Cronbach's α was 0.95; the Spearman-Brown coefficient was 0.92; and the intraclass correlation coefficient for the two measurements was 0.91. For the total score and for the scores of domains except the emotional role domain, the correlations were high and all the correlations were statistically significant. In conclusion, the Turkish version of the ICQ, which is a disease-specific, self-administered, and practical instrument, is reliable and valid. We recommend its use to assess the effect of IC on the quality of life of patients in clinical trials and in daily clinical practice.

Assessing the Quality of Available Patient Reported Outcome Measures for Intermittent Claudication: A Systematic Review Using the COSMIN Checklist

“…21 Translations are available in Turkish and German. 22,23 Content validity was rated positive since both experts in the field and patients were involved in the extensive development process. Limited evidence for uni-dimensionality of the ICQ in all languages was found.…”

Assessment of functional status and quality of life in claudication

“…The questionnaire has also been validated in Turkish. 110 Overall, testing for use in symptomatic PAD patients has been limited. However, the ICQ may be a practical tool for use in clinical settings, as the average time for completing the questionnaire is 3.7 minutes.…”

The metabolic efficiency of walking is reduced in patients with intermittent claudication

“…[7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In our study, the patients with IC preferred lower speeds than the healthy control group. Since the PWS is a gait parameter that can be used for assessing the overall gait performance, [10] we suggest that the PAD may have affected the gait performance of our patients with IC.…”

“…[17] Questionnaire Each of the participants filled out the IC questionnaire (Turkish version) prior to the treadmill walking trials. [18] This questionnaire is a disease-specific questionnaire for the assessment of health-related quality of life in patients with IC. [13] The validation and reliability of the Turkish version of the IC questionnaire was achieved by Ketenci et al, [18] and the score is assessed by using a 0-100 scale in which 0 represents the best possible score and 100 indicates the worst possible health condition.…”