Translation, Cultural Adaptation, Validation and Reliability of Persian Left Ventricular Dysfunction-36 Questionnaire

The left ventricular dysfunction 36 (LVD-36) questionnaire is considered to be a tool to assess the impact of left ventricle impairment on patients' daily life. This methodological study was aimed to translate and assess the validity and reliability of the Persian draft of the LVD-36 questionnaire among Iranian heart failure (HF) patients.

We recruited stable HF patients who referred to an outpatient heart clinic in Isfahan, Iran. The LVD-36 questionnaire was translated using the forward-backward method. Twenty HF patients were recruited for content validity assessment and were asked to express their opinions about the comprehensibility and meaningfulness of each item. We invited 14 experts to assess validity through content validity index (CVI) and content validity ratio (CVR). Reliability was assessed by Cronbach's alpha and intraclass correlation coefficient (ICC), with the latter evaluated after invitation of the participants to complete the questionnaire for the second time.

The translation process was performed uneventfully without any significant alterations. A total of 150 HF patients were recruited to assess the reliability of the questionnaire in this study (age: 64.6±16 years, males: 58.6%). All items had acceptable CVI and CVR, ranging 0.85-1.00 and 0.57-1.00, respectively. Cronbach's alpha was 0.971. All participants completed the questionnaire for the second time with no missing data. Test-retest reliability revealed an excellent ICC value of 0.981 (95% CI: 0.977-0.985).

The Persian version of the LVD-36 questionnaire is a simple, valid and reliable tool for evaluating the impact of left ventricle impairment on the well-being of Iranian HF patients.